JP2026005860A - Driving control system, work vehicle, and driving control method - Google Patents

Abstract

A travel control system, a work vehicle, and a travel control method are provided that enable a work vehicle to efficiently perform repetitive movements.
[Solution] The cruise control system includes a positioning device that outputs position data of a work vehicle, a sensor that detects the state of the work vehicle and outputs sensor data, and a control device. In a recording mode, the control device records a plurality of waypoint information in a storage device while the work vehicle is traveling, each of which includes first information related to the position of the work vehicle and second information related to the state of the work vehicle, and in a playback mode, controls the operation of the work vehicle while driving the work vehicle autonomously based on the plurality of waypoint information recorded in the recording mode. In the recording mode, if it is detected based on the position data and/or sensor data that the state of the work vehicle is not suitable for recording the plurality of waypoint information, the control device stops recording the plurality of waypoint information.
[Selected Figure] Figure 14

Description

This disclosure relates to a driving control system, a work vehicle, and a driving control method.

As a form of next-generation agriculture, research and development is underway into smart agriculture that utilizes ICT (Information and Communication Technology) and IoT (Internet of Things). Research and development is also underway to automate and unmanned tractors and other work vehicles used in fields. For example, work vehicles that can steer automatically using positioning systems such as the Global Navigation Satellite System (GNSS), which enables precise positioning, have been put into practical use.

Patent Document 1 discloses a work vehicle that can autonomously move between multiple rows of trees in an orchard such as a vineyard by utilizing SLAM (Simultaneous Localization and Mapping) technology, which simultaneously performs position estimation and map creation. Patent Document 1 describes a work vehicle that travels between multiple rows of trees in an orchard, using a work machine (agricultural implement) coupled to the work vehicle to perform tasks such as weeding and pest control.

International Publication No. 2022/107586

There is also a demand for automation and unmanned operation of work performed by work vehicles while traveling within a field (e.g., an orchard). Work performed by work vehicles while traveling within a field may involve the same task being repeated multiple times. For example, weeding and pest control work may be performed multiple times in the same field. When the same task is performed repeatedly, the work vehicle performs the same task while traveling the same route within the field in the same way. In such cases, if autonomous traveling using, for example, SLAM technology is performed every time, the processing load for autonomous traveling will increase more than necessary.

Efficient operation of work vehicles, which are performed repeatedly, is not limited to agricultural machinery; it is also required for work vehicles used for non-agricultural purposes, such as construction vehicles and snowplows. Furthermore, even when a work vehicle is traveling without performing work, it is required to travel the same route repeatedly and efficiently.

The present disclosure aims to provide a driving control system, work vehicle, and driving control method that can efficiently perform repetitive operations (including driving and other operations) of a work vehicle.

This disclosure provides the solutions described in the following items.

[Item A1]
A travel control system for a work vehicle,
a positioning device that detects the position of the work vehicle and outputs position data;
one or more sensors that detect the state of the work vehicle and output sensor data;
a control device for controlling the operation of the work vehicle,
The control device
capable of operating in record and play modes;
In the recording mode, while the work vehicle is traveling, based on the position data and the sensor data, a plurality of waypoint information pieces each including first information on the position of the work vehicle and second information on the state of the work vehicle are recorded in a storage device;
In the playback mode, the operation of the work vehicle is controlled while the work vehicle is traveling by automatic driving based on the first information and the second information included in the plurality of waypoint information recorded in the recording mode;
A driving control system that, in the recording mode, stops recording the plurality of waypoint information if it is detected based on the position data and/or the sensor data that the state of the work vehicle is not suitable for recording the plurality of waypoint information.

[Item A2]
The control device
The cruise control system described in item A1, wherein in the recording mode, if the state of the work vehicle satisfies a predetermined stopping condition based on the position data and/or the sensor data, recording of the plurality of waypoint information is stopped.

[Item A3]
The termination condition is:
the speed of the work vehicle is greater than a predetermined value;
the acceleration of the work vehicle is greater than a predetermined value; and the tilt angle of the work vehicle is greater than a predetermined value.
Including those who fall under any of the following:
The control device
The driving control system described in item A2, in the recording mode, determines whether the cancellation condition is met based on information on the speed of the work vehicle, information on the acceleration of the work vehicle, information on the inclination angle of the work vehicle, information on the engine rotation speed of the work vehicle, and information on the gear ratio of the transmission of the work vehicle, all obtained from the position data and/or the sensor data.

[Item A4]
The termination condition is:
a steering angle of a steering wheel of the work vehicle being greater than a predetermined value,
The control device
The cruise control system according to item A2 or A3, wherein in the recording mode, it is determined whether the cancellation condition is met based on information about the steering angle acquired from the sensor data.

[Item A5]
The termination condition is:
a rate of change per unit time of the steering angle of the steering wheels of the work vehicle being greater than a predetermined value,
The control device
The cruise control system according to any one of items A2 to A4, wherein in the recording mode, it is determined whether the cancellation condition is met based on information about the steering angle acquired from the sensor data.

[Item A6]
The termination condition is:
the work vehicle has less fuel than a predetermined amount;
The control device
The cruise control system according to any one of items A2 to A5, wherein in the recording mode, it is determined whether the cancellation condition is met based on information about the remaining amount of fuel obtained from the sensor data.

[Item A7]
The termination condition is:
The positioning device is experiencing a reception failure of a satellite signal,
The control device
The cruise control system according to any one of items A2 to A6, wherein in the recording mode, it is determined whether the cancellation condition is met based on information about satellites included in the data output from the positioning device.

[Item A8]
The termination condition is:
a data volume of the plurality of waypoint information stored in the storage device is greater than a predetermined value;
The control device
A cruise control system according to any one of items A2 to A7, wherein in the recording mode, it determines whether the cancellation condition is met based on information regarding the data capacity of the plurality of waypoint information stored in the storage device, which information is obtained from the storage device.

[Item A9]
The termination condition is:
the speed of the work vehicle is greater than a predetermined value;
the acceleration of the work vehicle is greater than a predetermined value;
the tilt angle of the work vehicle is greater than a predetermined value;
The rate of change per unit time of the tilt angle of the work vehicle is greater than a predetermined value;
The steering angle of the steering wheels of the work vehicle is greater than a predetermined value;
a rate of change per unit time of the steering angle of the steering wheels of the work vehicle is greater than a predetermined value;
The rate of change of the position of the work vehicle per unit time is greater than a predetermined value;
Wheel slippage of the work vehicle is detected;
that dashing of the work vehicle is detected;
the work vehicle has less fuel than a predetermined amount;
the battery voltage of the work vehicle is lower than a predetermined value;
The positioning device is experiencing interference with satellite signals;
A malfunction of the work vehicle has been detected;
It is detected that the driver's seat of the work vehicle is vacant;
The driving mode of the work vehicle has been changed to one that is not compatible with automatic driving.
The transmission of the work vehicle has been changed to a gear that is not compatible with autonomous driving,
The two brake pedals of the work vehicle are disconnected;
A predetermined condition regarding DPF regeneration of the work vehicle is satisfied;
A predetermined condition related to the SCR system of the work vehicle is satisfied;
The cruise control system according to any one of items A2 to A8, including the case where the time and/or distance traveled while recording the plurality of waypoint information is greater than a predetermined value, and the data capacity of the plurality of waypoint information recorded in the storage device is greater than a predetermined value.

[Item A10]
The control device
The driving control system according to any one of items A2 to A9, wherein when a signal including an instruction to start the recording mode is received, if the state of the work vehicle satisfies the cancellation condition, the recording mode is not started.

[Item A11]
The control device
The driving control system described in any one of items A1 to A10, wherein, when recording of the plurality of waypoint information is stopped in the recording mode, a display device provided in the work vehicle displays a message notifying a user that recording of the plurality of waypoint information has been stopped.

[Item A12]
The driving control system described in any one of items A1 to A11, wherein the second information includes at least one of information on the speed of the work vehicle, information on the engine speed of the work vehicle, information on the gear ratio of a transmission of the work vehicle, and information on the attitude of the work vehicle.

[Item A13]
A work machine is connected to the work vehicle,
the second information includes information regarding the operation of the work machine,
The control device
The travel control system according to any one of items A1 to A12, wherein, in the playback mode, the operation of the work machine is controlled based on the second information included in the plurality of waypoint information recorded in the recording mode.

[Item A14]
The travel control system according to item A13, wherein in the recording mode, the work vehicle travels while performing work using the work implement.

[Item A15]
The travel control system according to item A13, wherein in the recording mode, the work vehicle travels between a plurality of crop rows while performing work using the work implement.

[Item A16]
The work vehicle has a coupling device for connecting the work implement,
The cruise control system according to any one of items A13 to A15, wherein the second information includes information about a state of the coupling device.

[Item A17]
The coupling device includes a three-point hitch for adjusting the height of the work machine,
The cruise control system of claim A16, wherein the information regarding the state of the coupling device includes information regarding the height of the three-point hitch.

[Item A18]
the coupling device includes a PTO shaft that supplies power to the work machine,
The cruise control system of claim A16, wherein the information regarding the state of the coupling device includes information on whether rotation of the PTO shaft is on or off.

[Item A19]
A cruise control system according to any one of items A1 to A18;
a running device including a steering wheel;
a first drive device that drives the traveling device,
In the playback mode, the control device controls the first drive device based on the first information and the second information included in the plurality of waypoint information recorded in the recording mode, thereby causing the work vehicle to travel in an automatic driving manner.

[Item A20]
a work machine coupled to the work vehicle;
a second drive device that drives the work machine,
the second information includes information regarding the operation of the work machine,
The work vehicle described in item A19, wherein the control device controls the operation of the work implement by controlling the second drive device based on the second information included in the plurality of waypoint information recorded in the recording mode in the playback mode.

[Item B1]
A travel control system for a work vehicle,
a positioning device that detects the position of the work vehicle and outputs position data;
one or more sensors that detect the state of the work vehicle and output sensor data;
a control device for controlling the operation of the work vehicle,
The control device
capable of operating in record and play modes;
In the recording mode, while the work vehicle is traveling, based on the position data and the sensor data, a plurality of waypoint information pieces each including first information on the position of the work vehicle and second information on the state of the work vehicle are recorded in a storage device;
In the playback mode, the operation of the work vehicle is controlled while the work vehicle is traveling by automatic driving based on the first information and the second information included in the plurality of waypoint information recorded in the recording mode;
In the recording mode, when a user performs an operation to change the state of the work vehicle, if the state of the work vehicle as assumed to have been changed based on the operation is not suitable for recording the plurality of waypoint information, the driving control system restricts the change based on the operation.

[Item B2]
The control device
The driving control system described in item B1, wherein, in the recording mode, when an operation to change the state of the work vehicle is performed by a user, if the state of the work vehicle assumed to have been changed based on the operation satisfies a predetermined cancellation condition, the change based on the operation is restricted.

[Item B3]
The termination condition is:
The speed of the work vehicle is greater than a predetermined value, or the acceleration of the work vehicle is greater than a predetermined value,
The control device
The driving control system described in item B2, wherein, in the recording mode, when a user performs an operation to change the engine speed and/or the gear ratio of the transmission of the work vehicle, if the speed or acceleration of the work vehicle assuming that it has been changed based on the operation is greater than a predetermined value, the change in the engine speed and/or the gear ratio of the transmission is restricted.

[Item B4]
the cancellation condition includes a speed of the work vehicle being greater than a first value;
The control device
The driving control system described in item B3, wherein in the recording mode, when a user performs an operation to change the engine speed and/or the gear ratio of the transmission of the work vehicle, the speed of the work vehicle is set to be equal to or less than the first value.

[Item B5]
The control device
The first value is varied depending on the tilt angle of the work vehicle;
The cruise control system according to item B4, wherein the first value is made smaller as the tilt angle of the work vehicle increases.

[Item B6]
the cancellation condition includes a change in the driving mode of the work vehicle to a mode that does not support automatic driving of the work vehicle,
The control device
The driving control system according to any one of items B2 to B5, wherein, when an operation to change the driving mode is performed by a user in the recording mode, if the driving mode assumed to have been changed based on the operation is a mode that does not support autonomous driving, the driving mode is maintained.

[Item B7]
The control device
The driving control system according to item B6, wherein, in the recording mode, when a user performs an operation to change the driving mode from four-wheel drive mode to two-wheel drive mode, the driving mode is maintained in the four-wheel drive mode.

[Item B8]
The termination condition is:
The steering angle of the steering wheels of the work vehicle is greater than a predetermined value, or the rate of change of the steering angle per unit time is greater than a predetermined value,
The control device
The cruise control system according to any one of items B2 to B7, wherein, in the recording mode, when an operation to change the steering angle is performed by a user, the steering angle or a rate of change of the steering angle per unit time when assumed to have been changed based on the operation is greater than a predetermined value, and the cruise control system limits the change of the steering angle.

[Item B9]
The termination condition is:
the speed of the work vehicle is greater than a predetermined value;
the acceleration of the work vehicle is greater than a predetermined value;
The steering angle of the steering wheels of the work vehicle is greater than a predetermined value;
The rate of change of the steering angle per unit time is greater than a predetermined value.
The driving control system according to any one of items B2 to B8, including the case where either the inclination angle of the work vehicle is greater than a predetermined value, or the driving mode of the work vehicle has been changed to one that does not support automatic driving.

[Item B10]
The control device
The driving control system according to any one of items B1 to B9, wherein, in the recording mode, when restricting the change based on the operation, a display device provided in the work vehicle displays a message notifying a user that the change based on the operation is restricted.

[Item B11]
The cruise control system described in any one of items B1 to B10, wherein the second information includes at least one of information on the speed of the work vehicle, information on the gear ratio of a transmission of the work vehicle, information on the engine speed of the work vehicle, and information on the attitude of the work vehicle.

[Item B12]
A work machine is connected to the work vehicle,
the second information includes information regarding the operation of the work machine,
The control device
The travel control system according to any one of items B1 to B11, wherein, in the playback mode, the operation of the work machine is controlled based on the second information included in the plurality of waypoint information recorded in the recording mode.

[Item B13]
The travel control system according to item B12, wherein in the recording mode, the work vehicle travels while performing work using the work implement.

[Item B14]
The travel control system according to item B12, wherein in the recording mode, the work vehicle travels between a plurality of crop rows while performing work using the work implement.

[Item B15]
The work vehicle has a coupling device for connecting the work implement,
The cruise control system according to any one of items B12 to B14, wherein the second information includes information relating to a state of the coupling device.

[Item B16]
The coupling device includes a three-point hitch for adjusting the height of the work machine,
The cruise control system of claim B15, wherein the information regarding the state of the coupling device includes information regarding the height of the three-point hitch.

[Item B17]
the coupling device includes a PTO shaft that supplies power to the work machine,
The cruise control system of claim B15, wherein the information regarding the state of the coupling device includes information on whether rotation of the PTO shaft is on or off.

[Item B18]
A cruise control system according to any one of items B1 to B17;
a running device including a steering wheel;
a first drive device that drives the traveling device,
In the playback mode, the control device controls the first drive device based on the first information and the second information included in the plurality of waypoint information recorded in the recording mode, thereby causing the work vehicle to travel in an automatic driving manner.

[Item B19]
a work machine coupled to the work vehicle;
a second drive device that drives the work machine,
the second information includes information regarding the operation of the work machine,
The work vehicle described in item B18, wherein the control device controls the operation of the work implement by controlling the second drive device based on the second information included in the plurality of waypoint information recorded in the recording mode in the playback mode.

[Item C1]
A work vehicle travel control method executed by a control device that controls the operation of a work vehicle and is capable of operating in a recording mode and a playback mode, comprising:
In the recording mode, while the work vehicle is traveling, recording a plurality of waypoint information in a storage device, each of which includes first information regarding the position of the work vehicle and second information regarding the operation of the work vehicle, based on position data obtained from a positioning device that detects the position of the work vehicle and sensor data obtained from one or more sensors that detect the state of the work vehicle;
In the playback mode, controlling the operation of the work vehicle while causing the work vehicle to travel by automatic driving based on the first information and the second information included in the plurality of waypoint information recorded in the recording mode;
A driving control method that includes, in the recording mode, if it is detected based on the position data and/or the sensor data that the state of the work vehicle is not suitable for recording the plurality of waypoint information, stopping the recording of the plurality of waypoint information.

[Item C2]
A work vehicle travel control method executed by a control device that controls the operation of a work vehicle and is capable of operating in a recording mode and a playback mode, comprising:
In the recording mode, while the work vehicle is traveling, recording a plurality of waypoint information in a storage device, each of which includes first information regarding the position of the work vehicle and second information regarding the state of the work vehicle, based on position data acquired from a positioning device that detects the position of the work vehicle and sensor data acquired from one or more sensors that detect the state of the work vehicle;
In the playback mode, controlling the operation of the work vehicle while causing the work vehicle to travel by automatic driving based on the first information and the second information included in the plurality of waypoint information recorded in the recording mode;
When an operation to change the state of the work vehicle is performed by a user in the recording mode, if the state of the work vehicle assumed to have been changed based on the operation is not suitable for recording the plurality of waypoint information, the driving control method includes restricting the change based on the operation.

[Item C3]
A control device that executes the cruise control method according to item C1 or C2.

[Item C4]
A computer program executed by a computer that controls the operation of a work vehicle,
A computer program that causes the computer to execute the steps of the cruise control method according to item C1 or C2.

[Item C5]
A computer program medium executed by a computer that controls the operation of a work vehicle,
A computer program medium that causes the computer to execute the cruise control method according to item C1 or C2.

[Item C6]
A travel control system for a work vehicle,
a positioning device that detects the position of the work vehicle and outputs position data;
one or more sensors that detect the state of the work vehicle and output sensor data;
A cruise control system having the control device according to item C3.

[Item C7]
A control device for controlling the operation of a work vehicle, the control device being capable of operating in a recording mode and a playback mode,
a means for recording, in the recording mode, a plurality of waypoint information pieces each including first information relating to the position of the work vehicle and second information relating to the state of the work vehicle, in a storage device, based on position data acquired from a positioning device that detects the position of the work vehicle and sensor data acquired from one or more sensors that detect the state of the work vehicle, while the work vehicle is traveling;
a means for controlling, in the playback mode, the operation of the work vehicle while causing the work vehicle to travel by automatic driving based on the first information and the second information included in the plurality of waypoint information recorded in the recording mode;
and means for stopping recording of the plurality of waypoint information when, in the recording mode, it is detected based on the position data and/or the sensor data that the state of the work vehicle is not suitable for recording the plurality of waypoint information.

[Item C8]
A control device for controlling the operation of a work vehicle, the control device being capable of operating in a recording mode and a playback mode,
a means for recording, in the recording mode, a plurality of waypoint information pieces each including first information relating to the position of the work vehicle and second information relating to the state of the work vehicle, in a storage device, based on position data acquired from a positioning device that detects the position of the work vehicle and sensor data acquired from one or more sensors that detect the state of the work vehicle, while the work vehicle is traveling;
a means for controlling, in the playback mode, the operation of the work vehicle while causing the work vehicle to travel by automatic driving based on the first information and the second information included in the plurality of waypoint information recorded in the recording mode;
a control device that includes: when, in the recording mode, an operation to change the state of the work vehicle is performed by a user, if the state of the work vehicle as assumed to have been changed based on the operation is not suitable for recording the plurality of waypoint information, and

[Item C9]
A travel control system for a work vehicle,
a positioning device that detects the position of the work vehicle and outputs position data;
one or more sensors that detect the state of the work vehicle and output sensor data;
A cruise control system having the control device according to item C7 or C8.

[Item C10]
one or more processors;
and one or more memories that store a computer program that causes the one or more processors to execute the steps of the cruise control method described in item C1 or C2.

[Item C11]
The control device according to item C10;
a first drive device that drives a traveling device of the work vehicle,
In the playback mode, the control device controls the first drive device based on the first information and the second information included in the plurality of waypoint information recorded in the recording mode, thereby causing the work vehicle to travel in an automatic driving manner.

[Item C12]
a work machine coupled to the work vehicle;
a second drive device that drives the work machine,
the second information includes information regarding the operation of the work machine,
The control device controls the operation of the work machine by controlling the second drive device based on the second information included in the plurality of waypoint information recorded in the recording mode in the playback mode.

A general or specific aspect of the present disclosure may be realized by an apparatus, a system, a method, an integrated circuit, a computer program, or a computer-readable non-transitory storage medium, or any combination thereof. The computer-readable storage medium may include a volatile storage medium or a non-volatile storage medium. An apparatus may be composed of multiple devices. When an apparatus is composed of two or more devices, the two or more devices may be located within a single device, or may be located separately within two or more separate devices.

Embodiments of the present disclosure provide a travel control system, work vehicle, and travel control method that enable a work vehicle to efficiently perform repetitive operations (including travel and other operations).

1 is a side view schematically illustrating an example of a work vehicle according to an embodiment of the present disclosure. 1 is a block diagram schematically illustrating an example configuration of a work vehicle and a work machine according to an embodiment of the present disclosure. 1 is a block diagram illustrating a schematic configuration example of a cruise control system according to an embodiment of the present disclosure. 1 is a block diagram showing an example configuration of a control device included in a cruise control system according to an embodiment of the present disclosure. 1 is a schematic diagram illustrating a configuration example of a cruise control system according to an embodiment of the present disclosure. FIG. 1 is a diagram illustrating an example of an environment in which a work vehicle according to an embodiment of the present disclosure travels. FIG. 1 is a diagram schematically illustrating an example of a route traveled by a work vehicle in a recording mode according to an embodiment of the present disclosure. FIG. 1 is a diagram schematically illustrating an example of a route traveled by a work vehicle in a regeneration mode according to an embodiment of the present disclosure. FIG. 10 is a diagram schematically illustrating another example of a route traveled by a work vehicle according to an embodiment of the present disclosure. FIG. 10 is a diagram schematically illustrating another example of a route traveled by a work vehicle according to an embodiment of the present disclosure. 10 is a flowchart illustrating an example of a process performed by the control device in a recording mode. 10 is a flowchart illustrating an example of a process performed by the control device in a recording mode. 10 is a flowchart showing yet another example of the process performed by the control device in the recording mode. FIG. 10 is a diagram illustrating an example of waypoint information. 10 is a flowchart illustrating an example of a process performed by the control device in a playback mode. FIG. 2 is a diagram illustrating an example of a process performed by a control device of the cruise control system according to an embodiment of the present disclosure. FIG. 2 is a diagram illustrating an example of a process performed by a control device of the cruise control system according to an embodiment of the present disclosure. FIG. 2 is a diagram illustrating an example of a process performed by a control device of the cruise control system according to an embodiment of the present disclosure. 1 is a diagram showing an example of a group of operation switches and an operation terminal provided inside a cabin of a work vehicle. FIG. 10 is a flowchart illustrating an example of a process performed by the control device in a recording mode. 10 is a flowchart showing an example of a process performed by the control device when a signal including an instruction to start a recording mode is received. FIG. 2 is a schematic diagram for explaining an example of processing performed by a control device. 1 is a diagram showing an example of a brake operating device provided inside a cabin of a work vehicle. FIG. 10 is a flowchart showing an example of processing performed by the control device when a user performs an operation to change the state of the work vehicle in a recording mode. 10 is a flowchart showing an example of processing performed by the control device when a user performs an operation to change the state of the work vehicle in a recording mode. 10 is a flowchart showing an example of processing performed by the control device when a user performs an operation to change the state of the work vehicle in a recording mode. 10 is a flowchart showing an example of processing performed by the control device when a user performs an operation to change the state of the work vehicle in a recording mode.

(Definition of terms)
In this disclosure, a "work vehicle" refers to a vehicle used to perform work on a work site. A "work site" is any location where work can be performed, such as a farm field, forest, or construction site. A "field" is any location where agricultural work can be performed, such as an orchard, field, rice paddy, grain farm, or pasture. A work vehicle may be an agricultural machine such as a tractor, rice transplanter, combine harvester, riding cultivator, or riding brush cutter, or a vehicle used for non-agricultural purposes such as a construction vehicle or snowplow. A work vehicle may be configured to be able to mount a work implement (also called an "work device" or "implement") appropriate for the work to be performed on at least one of the front and rear of the work vehicle. In particular, a work implement mounted on an agricultural tractor is sometimes called an "agricultural implement." Traveling while performing work using the work implement is sometimes referred to as "work travel." The "operation" of a work vehicle includes not only travel of the work vehicle but also other operations.

"Autonomous driving" refers to controlling the vehicle's driving through the action of a control device, rather than through manual operation by the driver. During autonomous driving, not only the vehicle's driving but also work operations (e.g., the operation of work equipment) may be controlled automatically. Autonomous driving of a vehicle is referred to as "autonomous driving." The control device may control at least one of the following operations required for vehicle driving: steering, adjusting driving speed, and starting and stopping driving. When controlling a work vehicle equipped with work equipment, the control device may control operations such as raising and lowering the work equipment and starting and stopping the work equipment's operation. Autonomous driving may include not only driving the vehicle toward a destination along a predetermined route, but also driving while tracking a target. In addition to autonomous driving mode, an autonomously driving vehicle may operate in a manual driving mode, in which the vehicle is driven by manual operation by the driver. Driving by manual operation by the driver is referred to as "manual driving." "Manual operation by the driver" includes not only manual operation by the driver on the vehicle but also remote operation by a driver (operator) outside the vehicle. An autonomously driving vehicle may drive partially based on manual operation by the driver. "Automatic steering" refers to steering a vehicle by the function of a control device without manual operation by the driver. Part or all of the control device may be external to the vehicle. Control signals, commands, data, and the like may be communicated between the vehicle and a control device external to the vehicle. An autonomously driven vehicle may travel autonomously while sensing the surrounding environment, without human involvement in controlling the vehicle's travel. A vehicle capable of autonomous travel can travel unmanned. During autonomous travel, obstacles may be detected and obstacle avoidance operations may be performed.

A "crop row" is a row of crops, trees, or other plants growing in a field such as an orchard or a farm, or in a forest. In this disclosure, "crop row" is a concept that includes "tree row."

(Embodiment)
Hereinafter, embodiments of the present disclosure will be described. However, more detailed descriptions than necessary may be omitted. For example, detailed descriptions of well-known matters and redundant descriptions of substantially identical configurations may be omitted. This is to avoid unnecessary redundancy in the following description and to facilitate understanding by those skilled in the art. Note that the inventors provide the accompanying drawings and the following description to enable those skilled in the art to fully understand the present disclosure, and do not intend for them to limit the subject matter described in the claims. In the following description, components having the same or similar functions are designated by the same reference numerals.

The following embodiments are illustrative, and the technology of the present disclosure is not limited to the following embodiments. For example, the numerical values, shapes, materials, steps, and order of steps shown in the following embodiments are merely examples, and various modifications are possible as long as no technical contradictions arise. Furthermore, one aspect can be combined with another aspect.

As an example, the following describes an embodiment in which the work vehicle is a tractor used for agricultural work in fields such as orchards. The technology of the present disclosure is not limited to tractors, and can also be applied to other types of agricultural machinery, such as rice transplanters, combine harvesters, riding cultivators, and riding lawnmowers. The technology of the present disclosure can also be applied to work vehicles used for purposes other than agriculture, such as construction vehicles or snowplows. The technology of the present disclosure can also be applied to work vehicles traveling outside of work areas and traveling without work.

[General configuration of work vehicle]
Fig. 1 is a side view that schematically shows an example of a work vehicle 100 and a work implement 300 coupled to the work vehicle 100. Fig. 2 is a block diagram that schematically shows an example of the configuration of the work vehicle 100 and the work implement 300.

As shown in Figures 1 and 2, the work vehicle 100 is equipped with a positioning device 110 (e.g., a GNSS unit) that detects the position of the work vehicle 100 and outputs position data, a sensor group 150 that detects the state of the work vehicle 100 and outputs sensor data, and a control device 180 that controls the operation of the work vehicle 100. The sensor group 150 includes one or more sensors.

The work vehicle 100 may further be equipped with multiple external sensors that sense the surroundings of the work vehicle 100. An "external sensor" is a sensor that senses conditions outside the work vehicle. In the example of FIG. 1, the external sensors include multiple LiDAR sensors 140, multiple cameras 120, and multiple obstacle sensors 130.

In the example of Figure 2, the work vehicle 100 includes a positioning device 110, a camera 120, an obstacle sensor 130, a LiDAR sensor 140, a group of sensors 150, a memory device 170, a control device 180, and an operation terminal 200, as well as a communication device 190, a group of operation switches 210, and a drive device 240 (sometimes referred to as the "first drive device"). These components are connected to each other via a bus so that they can communicate with each other.

As shown in FIG. 1, the work vehicle 100 comprises a vehicle body 101, a prime mover (engine) 102, and a transmission 103. The vehicle body 101 is provided with a traveling device including wheels with tires 104, and a cabin 105. The traveling device includes four wheels 104, axles that rotate the four wheels, and braking devices (brakes) that brake each axle. The wheels 104 include a pair of front wheels 104F and a pair of rear wheels 104R. Inside the cabin 105 are a driver's seat 107, a steering device 106, an operation terminal 200, and a group of switches for operation. One or both of the front wheels 104F and the rear wheels 104R may be replaced with multiple wheels (crawlers) equipped with tracks rather than wheels with tires.

The prime mover 102 may be, for example, a diesel engine. An electric motor may be used instead of a diesel engine. The transmission 103 can change the propulsive force and travel speed of the work vehicle 100 by changing gears. The transmission 103 can also switch the work vehicle 100 between forward and reverse travel.

The steering device 106 includes a steering wheel, a steering shaft connected to the steering wheel, and a power steering device that assists steering by the steering wheel. The front wheels 104F are steerable wheels, and the traveling direction of the work vehicle 100 can be changed by changing their turning angle (also referred to as the "steering angle"). The steering angle of the front wheels 104F can be changed by operating the steering wheel. The power steering device includes a hydraulic device or electric motor that supplies auxiliary force to change the steering angle of the front wheels 104F. When automatic steering is performed, the steering angle is automatically adjusted by the power of the hydraulic device or electric motor under control of a control device located within the work vehicle 100.

A coupling device 108 is provided at the rear of the vehicle body 101. The coupling device 108 includes, for example, a three-point support device (also called a "three-point hitch" or "three-point link"), a PTO (Power Take Off) axle, a universal joint, and a communication cable. The coupling device 108 allows the work implement 300 to be attached and detached to the work vehicle 100. The coupling device 108 can raise and lower the three-point hitch using, for example, a hydraulic device, thereby changing the position or posture of the work implement 300. Power can also be sent from the work vehicle 100 to the work implement 300 via the universal joint. The work vehicle 100 can tow the work implement 300 and cause it to perform a specified task. The coupling device may be provided at the front of the vehicle body 101. In this case, the work implement can be connected to the front of the work vehicle 100.

The work implement 300 shown in FIG. 1 is a sprayer that sprays chemicals on crops, but the work implement 300 is not limited to a sprayer. For example, any work implement, such as a mower, seeder, spreader, rake, baler, harvester, plow, harrow, or rotary, can be connected to the work vehicle 100 and used.

The positioning device 110 receives satellite signals (also referred to as GNSS signals) transmitted from multiple GNSS satellites and performs positioning based on the satellite signals. GNSS is a general term for satellite positioning systems such as GPS (Global Positioning System), QZSS (Quasi-Zenith Satellite System, e.g., Michibiki), GLONASS, Galileo, and BeiDou. In this embodiment, the positioning device 110 is provided on top of the cabin 105, but may be provided in another location.

As shown in FIG. 2, the positioning device 110 includes a GNSS receiver 111, an RTK receiver 112, and a processing circuit 116. The positioning device 110 may further include an inertial measurement unit (IMU) 115.

The GNSS receiver 111 includes an antenna that receives signals from GNSS satellites and a processing circuit that determines the position of the work vehicle 100 based on the signals received by the antenna. The GNSS receiver 111 receives satellite signals transmitted from multiple GNSS satellites and generates GNSS data based on the satellite signals. The GNSS data is generated in a predetermined format, such as the NMEA-0183 format. The GNSS data may include, for example, values indicating the identification number, elevation angle, azimuth angle, and reception strength of each satellite from which the satellite signal is received.

The positioning device 110 may use RTK (Real Time Kinematic)-GNSS to determine the position of the work vehicle 100. RTK-GNSS positioning utilizes satellite signals transmitted from multiple GNSS satellites as well as correction signals transmitted from a reference station. The reference station may be installed near the work site where the work vehicle 100 will be traveling (e.g., within 10 km of the work vehicle 100). The reference station generates correction signals, for example, in RTCM format, based on the satellite signals received from multiple GNSS satellites and transmits them to the positioning device 110. The RTK receiver 112 includes an antenna and a modem and receives the correction signals transmitted from the reference station. The processing circuit 116 of the positioning device 110 corrects the positioning results obtained by the GNSS receiver 111 based on the correction signals. Using RTK-GNSS, it is possible to perform positioning with an accuracy of, for example, a few centimeters. Position information including latitude, longitude, and altitude information is obtained through highly accurate positioning using RTK-GNSS. The positioning device 110 calculates the position of the work vehicle 100, for example, at a frequency of approximately 1 to 10 times per second. Note that the positioning method is not limited to RTK-GNSS; any positioning method (such as interferometric positioning or relative positioning) that can obtain position information with the required accuracy can be used. For example, positioning may be performed using a Virtual Reference Station (VRS) or a Differential Global Positioning System (DGPS).

In this embodiment, the positioning device 110 further includes an IMU 115. By including the IMU 115, the positioning device 110 can complement position data using signals from the IMU 115. By using data acquired by the IMU 115 to complement position data based on satellite signals, positioning performance can be improved.

The IMU 115 may include a three-axis acceleration sensor and a three-axis gyroscope. The IMU 115 may also include a direction sensor such as a three-axis geomagnetic sensor. The IMU 115 functions as a motion sensor and can output signals indicating various quantities such as the acceleration, velocity, displacement, and attitude of the work vehicle 100. The processing circuit 116 can estimate the position and orientation of the work vehicle 100 with greater accuracy based on the signals output from the IMU 115 in addition to the satellite signals and correction signals. The signals output from the IMU 115 can be used to correct or complement the position calculated based on the satellite signals and correction signals. The IMU 115 outputs signals at a higher frequency than the GNSS receiver 111. For example, the IMU 115 outputs signals at a frequency of tens to thousands of times per second. Using these high-frequency signals, the processing circuit 116 can measure the position and orientation of the work vehicle 100 at a higher frequency (e.g., 10 Hz or higher). Instead of the IMU 115, a three-axis acceleration sensor and a three-axis gyroscope may be provided separately. The IMU 115 may also be provided as a device separate from the positioning device 110.

The sensor group 150 may include various sensors (i.e., internal sensors) that detect the state of the work vehicle 100 or work implement 300. For example, the sensor group 150 may include a steering wheel sensor 152, a turning angle sensor 154, and an axle sensor 156.

The steering wheel sensor 152 measures the rotation angle of the steering wheel of the work vehicle 100. The turning angle sensor 154 measures the turning angle of the front wheels 104F, which are the steered wheels. The measured values from the steering wheel sensor 152 and the turning angle sensor 154 can be used for steering control by the control device 180.

The axle sensor 156 measures the rotational speed of the axle connected to the wheel 104, i.e., the number of rotations per unit time. The axle sensor 156 may be a sensor that uses, for example, a magnetoresistive element (MR), a Hall element, or an electromagnetic pickup. The axle sensor 156 outputs a numerical value that indicates, for example, the number of rotations per minute (unit: rpm) of the axle. The axle sensor 156 is used to measure the speed of the work vehicle 100. The measurement value from the axle sensor 156 can be used for speed control by the control device 180.

The storage device 170 includes one or more storage media, such as flash memory or a magnetic disk. The storage device 170 stores various data generated by the positioning device 110, the camera 120, the obstacle sensor 130, the LiDAR sensor 140, the sensor group 150, and the control device 180. The data stored in the storage device 170 may include an environmental map of the environment in which the work vehicle 100 is traveling, an obstacle map generated sequentially during travel, and route data for autonomous driving. The storage device 170 also stores computer programs that cause each ECU in the control device 180 to perform various operations, which will be described later. Such computer programs may be provided to the work vehicle 100 via a storage medium (e.g., a semiconductor memory or an optical disk) or a telecommunications line (e.g., the Internet). Such computer programs may also be sold as commercial software.

The control device 180 includes multiple ECUs. The multiple ECUs include, for example, an ECU 181 for speed control, an ECU 182 for steering control, an ECU 183 for work machine control, and an ECU 184 for automatic driving control.

The ECU 181 controls the speed of the work vehicle 100 by controlling the prime mover 102, transmission 103, and brakes included in the drive unit 240.

The ECU 182 controls the steering of the work vehicle 100 by controlling the hydraulic device or electric motor included in the steering device 106 based on the measurement values of the steering wheel sensor 152.

The ECU 183 controls the operation of the three-point hitch and PTO shaft included in the coupling device 108 to cause the work machine 300 to perform the desired operation. The ECU 183 also generates signals that control the operation of the work machine 300 and transmits these signals from the communication device 190 to the work machine 300.

The ECU 184 performs calculations and controls to achieve autonomous driving based on data output from the positioning device 110, camera 120, obstacle sensor 130, LiDAR sensor 140, and sensor group 150. For example, the ECU 184 estimates the position of the work vehicle 100 based on data output from at least one of the positioning device 110, camera 120, and LiDAR sensor 140. In situations where the reception strength of satellite signals from GNSS satellites is sufficiently high, the ECU 184 may determine the position of the work vehicle 100 based solely on the data output from the positioning device 110. On the other hand, in an environment where there are obstructions such as trees that block the reception of satellite signals around the work vehicle 100, such as an orchard, the ECU 184 estimates the position of the work vehicle 100 using data output from the LiDAR sensor 140 or camera 120. During autonomous driving, ECU 184 performs calculations necessary for work vehicle 100 to travel along the target route based on the estimated position of work vehicle 100. ECU 184 sends a command to change the speed to ECU 181 and a command to change the steering angle to ECU 182. In response to the command to change the speed, ECU 181 changes the speed of work vehicle 100 by controlling prime mover 102, transmission 103, or brakes. In response to the command to change the steering angle, ECU 182 changes the steering angle by controlling steering device 106.

These ECUs enable the control device 180 to achieve autonomous driving. During autonomous driving, the control device 180 controls the drive device 240 based on the measured or estimated position of the work vehicle 100 and the target route that is generated sequentially. This allows the control device 180 to drive the work vehicle 100 along the target route.

The multiple ECUs included in the control device 180 can communicate with each other in accordance with a vehicle bus standard such as CAN (Controller Area Network). A faster communication method such as Automotive Ethernet (registered trademark) may be used instead of CAN. While each of the ECUs 181 to 184 is shown as an individual block in FIG. 2, their respective functions may be realized by multiple ECUs. An on-board computer that integrates at least some of the functions of the ECUs 181 to 184 may also be provided. The control device 180 may include ECUs other than ECUs 181 to 184, and any number of ECUs may be provided depending on the functions. Each ECU includes a processing circuit including one or more processors.

Camera 120 may be installed, for example, on the front, rear, left, and right sides of work vehicle 100. Camera 120 captures images of the environment around work vehicle 100 and generates image data. Images acquired by camera 120 may be transmitted to a terminal device for remote monitoring, for example. These images may be used to monitor work vehicle 100 when it is operating unmanned. Cameras 120 may be installed as needed, and the number of cameras is optional.

The LiDAR sensor 140 is an example of an external sensor that outputs sensor data indicating the distribution of features around the work vehicle 100. In the example of FIG. 1, two LiDAR sensors 140 are located at the front and rear of the cabin 105. The LiDAR sensors 140 may also be located in other positions (for example, the lower front of the vehicle body 101). While the work vehicle 100 is traveling, each LiDAR sensor 140 repeatedly outputs sensor data indicating the distance and direction to each measurement point of an object in the surrounding environment, or the two-dimensional or three-dimensional coordinate values of each measurement point. The number of LiDAR sensors 140 is not limited to two, and may be one, three, or more.

The LiDAR sensor 140 may be configured to output two-dimensional or three-dimensional point cloud data as sensor data. In this specification, "point cloud data" broadly means data indicating the distribution of multiple reflection points observed by the LiDAR sensor 140. The point cloud data may include, for example, coordinate values of each reflection point in two-dimensional or three-dimensional space, or information indicating the distance and direction of each reflection point. The point cloud data may also include brightness information of each reflection point. The LiDAR sensor 140 may be configured to repeatedly output point cloud data, for example, at a preset cycle. In this way, the external sensor may include one or more LiDAR sensors 140 that output point cloud data as sensor data.

The sensor data output from the LiDAR sensor 140 is processed by a control device that controls the autonomous driving of the work vehicle 100. While the work vehicle 100 is traveling, the control device can sequentially generate an obstacle map showing the distribution of objects present around the work vehicle 100 based on the sensor data output from the LiDAR sensor 140. The control device can also use an algorithm such as SLAM to piece together obstacle maps during autonomous driving to generate an environmental map. The control device can also estimate the position and orientation of the work vehicle 100 (i.e., self-localization) by matching the sensor data with the environmental map.

The multiple obstacle sensors 130 shown in FIG. 1 are provided at the front and rear of the cabin 105. The obstacle sensors 130 may also be located in other locations. For example, one or more obstacle sensors 130 may be provided at any position on the side, front, or rear of the vehicle body 101. The obstacle sensors 130 may include, for example, a laser scanner or ultrasonic sonar. The obstacle sensors 130 are used to detect surrounding obstacles during autonomous driving and to stop or detour the work vehicle 100.

The control device of the work vehicle 100 may use sensing data acquired by sensing devices such as the camera 120 or LiDAR sensor 140 for positioning, in addition to the positioning results from the positioning device 110. If there are features that function as characteristic points in the environment in which the work vehicle 100 is traveling, such as farm roads, forest roads, public roads, or orchards, the position and orientation of the work vehicle 100 can be estimated with high accuracy based on the data acquired by the camera 120 or LiDAR sensor 140 and an environmental map pre-stored in a storage device. By using the data acquired by the camera 120 or LiDAR sensor 140 to correct or complement position data based on satellite signals, the position of the work vehicle 100 can be determined with greater accuracy.

The work vehicle 100 and the work implement 300 can communicate with each other via a communication cable included in the coupling device 108. The work vehicle 100 can also communicate with a terminal device 400 for remote monitoring via the network 80. The terminal device 400 is any computer, such as a personal computer (PC), laptop computer, tablet computer, or smartphone.

The work machine 300 includes a drive unit 340 (sometimes referred to as the "second drive unit"), a control unit 380, and a communication unit 390. Note that Figure 2 shows components that are relatively closely related to the autonomous driving operation of the work vehicle 100, and does not depict other components.

The camera 120 is an imaging device that captures the environment surrounding the work vehicle 100. The camera 120 includes an image sensor, such as a charge-coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). The camera 120 may also include an optical system including one or more lenses and a signal processing circuit. The camera 120 captures the environment surrounding the work vehicle 100 while the work vehicle 100 is traveling and generates image (e.g., video) data. The camera 120 can capture video at a frame rate of, for example, 3 frames per second (fps) or higher. The images generated by the camera 120 can be used, for example, when a remote monitor uses the terminal device 400 to check the environment surrounding the work vehicle 100. The images generated by the camera 120 may also be used for positioning or obstacle detection. As shown in FIG. 1, multiple cameras 120 may be installed at different positions on the work vehicle 100, or a single camera may be installed. A visible light camera that generates visible light images and an infrared camera that generates infrared images may be provided separately. Both a visible light camera and an infrared camera may be provided as cameras that generate images for surveillance. The infrared camera may also be used to detect obstacles at night.

The obstacle sensor 130 detects objects present around the work vehicle 100. The obstacle sensor 130 may include, for example, a laser scanner or ultrasonic sonar. The obstacle sensor 130 outputs a signal indicating the presence of an obstacle when an object is present closer than a predetermined distance from the obstacle sensor 130. Multiple obstacle sensors 130 may be provided at different positions on the work vehicle 100. For example, multiple laser scanners and multiple ultrasonic sonars may be arranged at different positions on the work vehicle 100. By providing such a large number of obstacle sensors 130, blind spots in monitoring obstacles around the work vehicle 100 can be reduced.

The drive unit 240 includes various devices necessary for the travel of the work vehicle 100 and the driving of the work implement 300, such as the aforementioned prime mover 102, transmission 103, steering device 106, and coupling device 108. The prime mover 102 may be equipped with an internal combustion engine such as a diesel engine. The drive unit 240 may be equipped with an electric motor for traction instead of or in addition to the internal combustion engine.

The communication device 190 includes circuits for communicating with the work machine 300 and the terminal device 400. The communication device 190 includes circuits for transmitting and receiving signals compliant with ISOBUS standards, such as ISOBUS-TIM, between the communication device 390 of the work machine 300. This allows the work machine 300 to perform desired operations and acquire information from the work machine 300. The communication device 190 may also include an antenna and communications circuits for transmitting and receiving signals to and from the terminal device 400 via the network 80. The network 80 may include, for example, a cellular mobile communications network such as 3G, 4G, or 5G, and the Internet. The communication device 190 may also have the capability to communicate with a mobile device used by an observer located near the work vehicle 100. Communication with such a mobile device may be performed in accordance with any wireless communication standard, such as Wi-Fi (registered trademark), cellular mobile communications such as 3G, 4G, or 5G, or Bluetooth (registered trademark).

The operation terminal 200 is a terminal through which a user performs operations related to the travel of the work vehicle 100 and the operation of the work implement 300, and is also referred to as a virtual terminal (VT). The operation terminal 200 may include a display device such as a touch screen and/or one or more buttons. The display device may be, for example, a liquid crystal display or an organic light-emitting diode (OLED) display. By operating the operation terminal 200, a user can perform various operations, such as switching the autonomous driving mode on/off, switching the recording (teaching) mode and playback mode (described below) on/off, and switching the work implement 300 on/off. At least some of these operations can also be performed by operating the operation switch group 210. The operation terminal 200 may be configured to be detachable from the work vehicle 100. A user located away from the work vehicle 100 may operate the detached operation terminal 200 to control the operation of the work vehicle 100. The operation terminal 200 may include a storage device. The storage device in the operation terminal 200 may store various data necessary for the operation of the work vehicle 100 instead of the storage device 170. The drive device 340 in the work implement 300 shown in FIG. 2 performs the operations necessary for the work implement 300 to perform a predetermined task. The drive device 340 includes devices appropriate for the intended use of the work implement 300, such as a hydraulic device, an electric motor, or a pump. The control device 380 controls the operation of the drive device 340. The control device 380 causes the drive device 340 to perform various operations in response to signals transmitted from the work vehicle 100 via the communication device 390. In addition, signals appropriate to the state of the work implement 300 can also be transmitted from the communication device 390 to the work vehicle 100.

[Drive control system]
A cruise control system according to an embodiment of the present disclosure will be described. The cruise control system according to the embodiment of the present disclosure is applied to, for example, the work vehicle 100 described above. Note that, although the example in Figures 1 and 2 shows a work implement 300 coupled to the work vehicle 100, it is not essential that the work implement 300 be coupled to the work vehicle 100. In other words, the cruise control system according to the embodiment of the present disclosure can also be applied to a work vehicle 100 to which no work implement 300 is coupled.

3A is a block diagram showing a schematic configuration example of a cruise control system 1000 according to an embodiment of the present disclosure. As shown in FIG. 3A, the cruise control system 1000 according to this embodiment includes a positioning device 110 that detects the position of the work vehicle 100 and outputs position data, one or more sensors (sensor group) 150 that detect the state of the work vehicle 100 and output sensor data, and a control device 180 that controls the operation of the work vehicle 100. In this embodiment, as shown in FIG. 2, the positioning device 110, sensor group 150, and control device 180 are provided on the work vehicle 100. The control device 180 functions as the cruise control system 1000 for the work vehicle 100 in cooperation with the positioning device 110 and sensor group 150. The control device 180, positioning device 110, and sensor group 150 can be connected to each other so that they can communicate with each other via a bus 810.

3A also shows a storage device 870 in which information acquired by the control device 180 is recorded. The storage device 870 may be included in the control system 1000 or may be an element external to the control system 1000. The storage device 870 may be mounted on the work vehicle 100 or the work implement 300. The storage device 870 may be communicatively connected to the control device 180 via the bus 810. For example, the storage device 870 may be the storage device 170 shown in FIG. 2 or a storage device included in the operation terminal 200. The operation terminal 200 may be included in the cruise control system 1000. The storage device 870 may be located external to the work vehicle 100 and the work implement 300. A storage device 870 located external to the work vehicle 100 and the work implement 300 may be connected to the control device 180 via a communication network.

In the example shown in FIG. 1, the positioning device 110 is attached to the work vehicle 100, but the positioning device 110 may also be attached to a work implement 300 coupled to the work vehicle 100. In addition to or instead of the positioning device attached to the work vehicle 100, a positioning device (e.g., a GNSS unit) attached to the work implement 300 may function as the positioning device 110 of the cruise control system 1000. The position measured by the positioning device attached to the work vehicle 100 or work implement 300 is strictly speaking the position of the point where the positioning device is located, but in this specification this position will be referred to as the "position of the work vehicle."

The sensor group 150 is not limited to the steering wheel sensor 152, steering angle sensor 154, and axle sensor 156 described above, but may also include various sensors mounted on the work vehicle 100. For example, the sensor group 150 may include one or more sensors selected from a temperature sensor, an illuminance sensor, a fuel sensor, a water temperature sensor, an oil level gauge, an engine rotation sensor, a vehicle speed sensor, a battery voltage sensor, a shuttle sensor, a hand accelerator sensor, an accelerator pedal sensor, a main shift lever sensor, an auxiliary shift lever sensor, a seat belt sensor, a PM sensor, an acceleration sensor, an angular velocity sensor, an IMU (Inertial Measurement Unit), and a geomagnetic sensor. The sensor group 150 may also include a PTO sensor that detects the on/off rotation of the PTO shaft and/or a 3P position sensor that detects the height position of the three-point hitch (hereinafter simply referred to as "height"). Furthermore, in addition to or instead of one or more sensors mounted on the work vehicle 100, one or more sensors mounted on the work implement 300 may be included in the sensor group 150 of the cruise control system 1000.

In the example shown in FIG. 3A, the control device 180 includes multiple ECUs. These ECUs may include, for example, ECUs 181 to 184 shown in FIG. 2. However, the control device 180 may also be a single ECU or other computing device. FIG. 3B is a block diagram showing an example configuration of such a control device 180. In the example of FIG. 3B, the control device 180 includes a processor 281, a ROM (Read Only Memory) 283, a RAM (Random Access Memory) 285, a communication device 287, and a storage device 289. These components may be connected to each other via a bus 290.

The processor 281 is a semiconductor integrated circuit, and is also referred to as a central processing unit (CPU) or microprocessor. The processor 281 may include a graphics processing unit (GPU). The processor 281 sequentially executes a computer program containing a predetermined set of instructions stored in the ROM 283, thereby realizing the processing performed by the cruise control system of the present disclosure. The control device 180 may be equipped with multiple processors 281. The processing performed by the cruise control system of the present disclosure may be performed collaboratively by the multiple processors 281. Some or all of the processors 281 may be a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), or an application specific standard product (ASSP) equipped with a CPU.

The communication device 287 is an interface for data communication between the control device 180 and an external computing device. The communication device 287 can perform wired communication using a controller area network (CAN) or wireless communication conforming to the Bluetooth (registered trademark) standard and/or Wi-Fi (registered trademark) standard.

The storage device 289 can store data such as position data acquired from the positioning device 110, sensor data acquired from the sensor group 150, position data and/or sensor data during processing, first information acquired from the position data, and second information acquired from the sensor data. The storage device 289 includes, for example, a hard disk drive or non-volatile semiconductor memory. In this example, the storage device 289 may function as the storage device 870 in the example of FIG. 3A.

The hardware configuration of the control device 180 is not limited to the above example. Part or all of the control device 180 does not need to be installed on the work vehicle 100. By using the communication device 287, it is also possible to have one or more computing devices located outside the work vehicle 100 function as part or all of the control device 180. For example, one or more server computers and/or one or more computing devices included in a terminal device connected to a network can function as part or all of the control device 180. Alternatively, one or more computing devices installed on the work vehicle 100 may perform all of the functions required of the control device 180.

Figure 4 is a schematic diagram showing another example configuration of a cruise control system according to an embodiment of the present disclosure. The system shown in Figure 4 includes a work vehicle 100, another work vehicle 700, a server computer 500, and multiple terminal devices 600. The terminal device 600 may be either a portable or fixed terminal device. Some or all of the functions of the control device 180 shown in Figure 3B may be implemented by one or more computing devices connected to the communication device 287 of the control device 180 in the work vehicle 100 via a communication network 800. Such computing devices may be the server computer 500 or the terminal device 600. Other work vehicles (e.g., agricultural machinery) 700 may be connected to such a communication network 800. Communication may take place between the control device 180 in the work vehicle 100 and the other work vehicle 700. Some of the data used for processing by the control device 180 in the work vehicle 100 may be provided to the control device 180 from the other work vehicle 700 via the communication network 800. For example, waypoint information defining a route and a series of operations generated by a control device in another work vehicle 700 may be transmitted from the other work vehicle 700 to the control device 180 of the work vehicle 100. Based on this waypoint information, the control device 180 can execute playback operations in a playback mode, which will be described later.

As shown in FIG. 3B, one example of a "controller" in this disclosure is a computing device including at least one processor and at least one memory that stores a computer program (code) defining a control process executed by the processor. The "controller" may also be a computing device that includes a hardware accelerator, such as a field-programmable gate array (FPGA), application-specific standard product (ASSP), or application-specific integrated circuit (ASIC), configured to execute the control process.

In this disclosure, a "processor" refers to a hardware electronic circuit such as a CPU (Central Processing Unit), GPU (Graphics Processing Unit), DSP (Digital Signal Processor), ISP (Image Signal Processor), or NPU (Neural Network Processing Unit). "Memory" refers to a hardware electronic circuit such as ROM (Read Only Memory) or RAM (Random Access Memory). Part of the memory may be storage media connected to the processor by wiring or a network. These hardware electronic circuits may be implemented by one or more integrated circuits (ICs) or large-scale integrated circuits (LSIs). Each functional unit or block and related components within the electronic circuit may be manufactured individually as a separate integrated circuit chip, or some or all of these functional units or blocks may be combined and manufactured as a single integrated circuit chip.

The program that defines the operation of the processor is designed to cause the processor to perform one or more functions, operations, steps, or processes in the embodiments of the present disclosure.

[Recording and Playback Modes]
As described below, the cruise control system 1000 is capable of controlling the operation of the work vehicle 100 using a so-called teaching/playback method used in the field of robot control. The control device 180 in the cruise control system 1000 can operate in a recording mode and a playback mode. The recording mode is a mode in which multiple positions (hereinafter also referred to as "waypoints") that define the travel path of the work vehicle 100 and the operation at each waypoint are recorded. The playback mode is a mode in which the travel path of the work vehicle 100 and the operation at each waypoint that were recorded in the recording mode are reproduced. The operations in the recording mode and the playback mode correspond to the teaching operation and the playback operation, respectively, in the teaching/playback method. The operation of the control device 180 in the recording mode and the playback mode may be referred to as "teaching" and "playback," respectively. The recording mode may also be referred to as the "teaching mode," and the playback mode may also be referred to as the "playback mode."

With reference to Figures 5, 6A, and 6B, the operation of the control device 180 in the driving control system 1000 in recording mode and playback mode will be described. Figure 5 is a diagram that schematically shows an example of an environment in which the work vehicle 100 travels. Figure 6A is a diagram that schematically shows an example of a route 30T along which the work vehicle 100 travels in recording mode. Figure 6B is a diagram that schematically shows an example of a route 30P along which the work vehicle 100 travels in playback mode. In this example, the work vehicle 100 travels between multiple tree rows 20 (hereinafter also referred to as "crop rows 20") in an orchard such as a vineyard, and performs predetermined work (e.g., mowing, pest control, sowing seeds, fertilizing, etc.) using the work implement 300.

(recording mode)
In the example of FIG. 6A , in the recording mode, the work vehicle 100 travels while performing work using the work implement 300. In the example of FIG. 6A , the work vehicle 100 travels along a route 30T from a start point 30S to an end point 30G. FIG. 6A illustrates a state in which the work vehicle 100 is located just before the start point 30S, and a state in which the work vehicle 100 is located beyond the end point 30G. In the recording mode, while the work vehicle 100 is traveling, the control device 180 records multiple pieces of waypoint information in the storage device 870 based on the position data output from the positioning device 110 and the sensor data output from the sensor group 150. Each piece of waypoint information includes first information related to the position of the work vehicle 100 and second information related to the status of the work vehicle 100. The first information and second information included in each piece of waypoint information indicate the position of the work vehicle 100 and the status of the work vehicle 100 at that position, respectively. Therefore, the first information may be referred to as "position information" and the second information may be referred to as "status information." The multiple pieces of first information included in the multiple pieces of waypoint information indicate the route 30T traveled by the work vehicle 100. Each of the multiple pieces of second information included in the multiple pieces of waypoint information is recorded in association with the corresponding first information. By recording each of the multiple pieces of second information included in the multiple pieces of waypoint information in association with the corresponding first information, information on the status of the work vehicle 100 at each position on the route 30T traveled by the work vehicle 100 is recorded. For example, as shown in FIG. 6A , the first information and the second information are acquired at each of the multiple positions (waypoints) Pr on the traveled route 30T and recorded as waypoint information.

In recording mode, the work vehicle 100 may be manually driven by the driver, or may be automatically driven. When the work vehicle 100 is automatically driven in recording mode, it may be driven autonomously without manual operation by the driver, or it may be driven automatically while partially based on manual operation by the driver. For example, automatic steering control, in which the driver controls the driving speed of the work vehicle 100 and automatically controls the steering, may be performed during driving in recording mode. Alternatively, during driving in recording mode, the work vehicle 100 may be automatically driven while the work equipment 300 is operated by manual operation by the driver. Manual operation by the driver includes not only manual operation by the driver on the work vehicle 100, but also remote operation by a driver (operator) outside the work vehicle 100. Such remote operation may be performed, for example, using the terminal device 600 shown in FIG. 4 or another remote control device.

The second information broadly includes information relating to the state of the work vehicle 100 other than its position. The second information includes, for example, information relating to the operation of the work vehicle 100, such as its driving state. The driving state of the work vehicle 100 is determined by the speed, acceleration (i.e., the rate of change of speed per unit time), driving direction (heading), etc. of the work vehicle 100. Information relating to the driving state of the work vehicle 100 includes, for example, one or more of information on the speed of the work vehicle 100, information on the engine speed of the work vehicle 100, information on the acceleration of the work vehicle 100, information on the heading of the work vehicle 100, information on the steering angle of the steering wheels of the work vehicle 100, and information on the gear ratio of the transmission 103 of the work vehicle 100. The second information may also include information on the attitude of the work vehicle 100. Information on the attitude of the work vehicle 100 includes, for example, information on the heading of the work vehicle 100. The second information is not limited to information relating to the operation of the work vehicle 100, but may also include, for example, information about the temperature in the work vehicle 100 (e.g., the temperature of the engine coolant), information about the presence or absence of a malfunction in the work vehicle 100 (e.g., a diagnostic trouble code: DTC), etc. Specific examples of methods for acquiring the second information will be described later.

The second information may include information regarding the status of the coupling device 108 for coupling the work implement 300. The coupling device 108 may include, for example, a PTO shaft that supplies power to the work implement 300 and a three-point hitch that adjusts the height of the work implement 300. The information regarding the status of the coupling device 108 may include, for example, one or more of information regarding whether the rotation of the PTO shaft is on or off and information regarding the height of the three-point hitch.

When a work implement 300 is coupled to the work vehicle 100, the second information may include information regarding the state of the work implement 300 in addition to information regarding the state of the work vehicle 100. For example, if a positioning device is attached to the work implement 300, the second information may include information regarding the position or orientation of the work implement 300 (e.g., the angle relative to a reference orientation). Alternatively, if the work implement 300 is equipped with a sensor that detects the operation of a movable part of the work implement 300, the second information may include information detected by that sensor.

(Playback mode)
In playback mode, the work vehicle 100 travels by autonomous driving. The control device 180 controls the operation of the work vehicle 100 while causing the work vehicle 100 to travel automatically, based on the first information and second information included in the plurality of waypoint information recorded in recording mode. In the example of FIG. 6B , the work vehicle 100 travels automatically based on the first information (position information) and second information (status information) included in the plurality of waypoint information recorded when traveling along a route 30T (see FIG. 6A ) in recording mode. In playback mode, the control device 180 causes the work vehicle 100 to travel along a target route 30P defined by the first information included in the plurality of waypoint information recorded in recording mode. For example, the control device 180 performs steering control of the work vehicle 100 so as to minimize deviations in the position and orientation (azimuth) of the work vehicle 100 relative to the target route 30P. This allows the work vehicle 100 to travel along the target route 30P. In the playback mode, the work vehicle 100 can automatically reproduce the operation of the work vehicle 100 that was recorded in the recording mode.

The playback mode begins, for example, when the work vehicle 100 is located at the start point 30S of the target route 30P. The control device 180 ends the playback mode, for example, when the work vehicle 100 reaches the end point 30G of the target route 30P. Figure 6B illustrates examples of a state in which the work vehicle 100 is located just before the start point 30S and a state in which the work vehicle 100 is located midway along the route 30P.

As in the examples of Figures 6A and 6B, when a work implement 300 is coupled to the work vehicle 100, the control device 180 can control the operation of the work vehicle 100 and the work implement 300 while causing the work vehicle 100 to travel automatically, based on the first information and second information contained in the multiple waypoint information recorded in recording mode. In other words, in playback mode, the work vehicle 100 can automatically reproduce the operation of the work implement 300 in addition to the operation of the work vehicle 100 recorded in recording mode.

The driving control system of this embodiment can reproduce in playback mode the operation of the work vehicle 100 that was recorded in recording mode, allowing the work vehicle 100 to perform repetitive operations efficiently. In recording mode, second information regarding conditions other than the position of the work vehicle 100 is recorded in association with first information regarding the position of the work vehicle 100, thereby facilitating the automation and unmanned operation of the work vehicle 100.

When a work implement 300 is coupled to the work vehicle 100, in playback mode the work vehicle 100 can automatically reproduce the operation of the work implement 300 in addition to the operation of the work vehicle 100 recorded in recording mode, thereby enabling repetitive work performed by the work implement 300 to be performed efficiently. In recording mode, second information regarding the status of the work implement 300 is recorded in association with first information regarding the position of the work vehicle 100, thereby promoting automation and unmanned operation of work performed by the work implement 300.

6A and 6B, the work vehicle 100 travels between multiple tree rows 20 along path 30T or path 30P. More specifically, the work vehicle 100 travels between two adjacent tree rows 20, turning at a headland before and after traveling between the two adjacent tree rows 20. The headland is the area between the end of each tree row and the boundary of the orchard. Specifically, the following operation may be performed: The multiple tree rows 20 are ordered from the end as follows: first tree row 20A, second tree row 20B, third tree row 20C, fourth tree row 20D, etc. The work vehicle 100 first travels between the first tree row 20A and the second tree row 20B from a starting point 30S, and upon completing this travel, turns right and travels in the reverse direction between the second tree row 20B and the third tree row 20C. After completing travel between the second row of trees 20B and the third row of trees 20C, the vehicle turns further left and travels between the third row of trees 20C and the fourth row of trees 20D. By repeating the same operation, the vehicle travels to the end point 30G of route 30T or route 30P.

(Another example of a driving route)
7 and 8 are diagrams that schematically show other examples of routes that the work vehicle 100 travels.

Figure 7 shows a route 30A along which a work vehicle 100 travels between multiple crop rows 20 in a non-rectangular field 70P. In recording mode, the work vehicle 100 travels along route 30A from a start point 30S to an end point 30G. In playback mode, the control device 180 automatically drives the work vehicle 100 along a target route defined by the first information included in the multiple waypoint information recorded in recording mode. As shown in Figure 7, in non-rectangular fields, the lengths of the crop rows 20 may vary, making autonomous driving difficult. By using the driving control system of this embodiment, the work vehicle 100 can efficiently perform repetitive operations even in non-rectangular fields, thereby facilitating the automation and unmanned operation of the work vehicle 100.

Figure 8 shows a route 30B along which the work vehicle 100 travels outside the field 70. The area shown in Figure 8 includes multiple fields 70 where the work vehicle 100 performs agricultural work, and roads 76 in the surrounding areas. The roads 76 may be farm roads. In recording mode, the work vehicle 100 travels along route 30B from the start point 30S to the end point 30G. In playback mode, the control device 180 automatically drives the work vehicle 100 along a target route defined by the first information included in the multiple waypoint information recorded in recording mode. As in the example shown in Figure 8, the driving control system of this embodiment can also be applied to driving outside of a field. For example, it can be suitably applied to repeated driving, such as movement of the work vehicle 100 between fields, or movement of the work vehicle 100 between a storage location and a field. In such cases, the repetitive operation (here, movement) of the work vehicle 100 can be performed efficiently, facilitating automation and unmanned operation of the operation (here, movement) of the work vehicle 100.

(Example of processing in recording mode)
FIG. 9A is a flowchart showing an example of processing performed by the control device 180 in the recording mode.

The timing for starting the recording mode is specified, for example, by the user. For example, the driver may operate the control device 180 to send a signal containing an instruction to start the recording mode, causing the control device 180 to start the recording mode. For example, the driver of the work vehicle 100 can send a signal containing an instruction to start the recording mode to the control device 180 by operating a predetermined operation switch provided in the work vehicle 100 or an input device such as the operation terminal 200. The recording mode may be started while the work vehicle 100 is traveling, or may be started when the work vehicle 100 is stopped.

When the recording mode is initiated, in step S102, the control device 180 generates first information and second information based on the position data output from the positioning device 110 and the sensor data output from the sensor group 150 while the work vehicle 100 is traveling. For example, the control device 180 may calculate the position (i.e., coordinates) of a reference point of the work vehicle 100 based on the position data output from the positioning device 110, and generate (acquire) information indicating that position as the first information. The control device 180 can calculate the position of the reference point of the work vehicle 100 based on the position data output from the positioning device 110 and information indicating the relative positional relationship between the positioning device 110 and the work vehicle 100, which is pre-recorded in the storage device. The control device 180 may also generate, as the second information, information necessary for controlling various actuators that are driven during playback, based on the sensor data output from the sensor group 150.

The first information and second information may be generated at any timing. For example, the first information and second information may be generated every time the work vehicle 100 travels a certain distance, or every certain time. The certain distance (for example, in the example of FIG. 6A, the distance between two adjacent waypoints Pr in the direction of travel of the work vehicle 100) may be set to a value of, for example, several tens of centimeters (cm) to several meters (m). The certain time may be set to a value within the range of, for example, 1 to 10 seconds.

In step S104, the control device 180 records the waypoint information, including the first information and second information generated in step S102, in the storage device 870 (see Figure 3A). The first information and second information are recorded in association with each other.

Figure 10 is a diagram showing an example of waypoint information. The waypoint information shown in Figure 10 includes a waypoint number (No.) 90, first information 91 indicating the position of the work vehicle 100, and second information 92 indicating the status of the work vehicle 100. The first information 91 indicates the position coordinates of the waypoint. The position coordinates may indicate, for example, latitude and longitude in a geographic coordinate system, or may indicate position coordinates in a coordinate system different from the geographic coordinate system. The position coordinates may include altitude information in addition to latitude and longitude. The second information 92 in the example of Figure 10 includes information indicating the vehicle speed, steering angle, whether the brakes are applied, whether the PTO axle is on or off, and the height of the 3P hitch. The second information 92 may include only some of this information. Alternatively, the second information 92 may include other information not shown in Figure 10. For example, the second information 92 may include information indicating the status of the forward/reverse lever. Alternatively, the second information 92 may include ON/OFF information for the front wheel speed increase function (also called "double speed turn").

The control device 180 repeats the processing of steps S102 and S104 until a command to end the recording mode is issued (step S106). The timing of ending the recording mode can be specified by the user. For example, the driver may operate an input device such as the operation terminal 200 to send a signal to the control device 180 containing an instruction to end the recording mode, causing the control device 180 to end the recording mode. For example, the driver of the work vehicle 100 can send a signal to the control device 180 containing an instruction to end the recording mode by operating a predetermined operation switch provided on the work vehicle 100 or an input device such as the operation terminal 200.

Figure 9B is a flowchart showing another example of processing performed by the control device 180 in recording mode. The flowchart in Figure 9B differs from the flowchart in Figure 9A in that step S104 is performed after driving in recording mode has ended.

In the example shown in FIG. 9B, the control device 180 executes the processing of step S104 after the work vehicle 100 has completed traveling in recording mode (step S103). In step S104, a plurality of waypoint information items including the first information and second information generated while the work vehicle 100 was traveling in step S102 are recorded in the storage device 870. The first information and second information generated in step S102 may be temporarily stored in the storage device 870 or a storage device different from the storage device 870 (for example, a memory such as RAM 285 shown in FIG. 3B), and may be erased after the waypoint information is recorded. In this example, after traveling in recording mode has completed, waypoint information such as that shown in FIG. 10 is generated and recorded for each waypoint.

Figure 9C is a flowchart showing yet another example of processing performed by the control device 180 in recording mode. The flowchart shown in Figure 9C differs from the flowchart shown in Figure 9B in that the first information and second information are generated after driving in recording mode has ended.

In the example shown in FIG. 9C, in step S101, the control device 180 stores the position data output from the positioning device 110 and the sensor data output from the sensor group 150 in memory (e.g., RAM 285 shown in FIG. 3B) while the work vehicle 100 is traveling. After the work vehicle 100 has completed traveling in recording mode (step S103), the control device 180 executes the processes of steps S105 and S107. In step S105, the control device 180 generates first information and second information for each of a plurality of waypoints based on the position data and sensor data stored in memory. In step S107, the control device 180 records a plurality of waypoint information, each of which includes the first information and the second information, in the storage device 870. In this example, after traveling in recording mode has completed, the first information and second information are generated for each waypoint, and waypoint information such as that shown in FIG. 10 is recorded for each waypoint.

(Example of processing in playback mode)
FIG. 11 is a flowchart showing an example of processing performed by the control device 180 in the playback mode.

In playback mode, the control device 180 automatically drives the work vehicle 100 based on pre-recorded waypoint information. The control device 180 acquires position data indicating the position of the work vehicle 100 output from the positioning device 110 (step S121). Next, the control device 180 calculates the deviation between the position of the work vehicle 100 and the target route (step S122). The target route is defined by the position information (first information) of multiple waypoints recorded in recording mode. The deviation represents the distance between the position of the work vehicle 100 at that time and the target route. The control device 180 determines whether the deviation of the calculated position exceeds a preset threshold (step S123). If the deviation exceeds the threshold ("Yes" in step S123), the control device 180 changes the steering angle by changing the control parameters of the steering device 106 included in the drive device 240 so as to reduce the deviation (step S124). If the deviation does not exceed the threshold value in step S123 ("No" in step S123), the process of step S124 is not performed. The control device 180 repeats the operations of steps S121 to S124 until an instruction to end the playback mode is issued (step S125).

In playback mode, the control device 180 automatically drives the work vehicle 100 along the target route by executing the processing shown in FIG. 11, for example. The control device 180 further controls the operation of the work vehicle 100 based on status information (second information) corresponding to each of the multiple waypoints that define the target route. For example, if the second information includes information on the steering angle of the steering wheels of the work vehicle 100, in addition to the processing shown in FIG. 11, steering of the work vehicle 100 is controlled based on the steering angle included in the second information. If the second information includes information on the speed of the work vehicle 100, the speed of the work vehicle 100 is controlled based on the speed information included in the second information. In addition, for example, if an operation is recorded in which the rotation of the PTO shaft is stopped (turned off) before the start of a turn and the rotation of the PTO shaft is started (turned on) after the turn is completed, the control device 180 reproduces that operation when the work vehicle 100 turns in playback mode.

Control techniques such as PID control or MPC (model predictive control) control can be applied to the steering control and speed control of the work vehicle 100. By applying these control techniques, it is possible to smoothly control the work vehicle 100 to approach the target path and target speed.

(When the second information includes information regarding the traveling state of the work vehicle)
With reference to Fig. 12A , an example of processing performed by the control device 180 when the second information includes information related to the traveling state of the work vehicle 100 will be described. Fig. 12A is a schematic diagram for explaining an example of processing performed by the control device 180 in the traveling control system 1000. In addition to the traveling control system 1000, Fig. 12A also shows the drive device 240 and the operation switch group 210. For simplicity, some components are not shown in Fig. 12A.

(Control of work vehicle speed)
The control device 180 controls the speed of the work vehicle 100 by controlling the prime mover 102, braking device (brake) 293, and transmission 103 included in the drive device 240. The braking device 293 brakes the axle that rotates the wheels 104 of the work vehicle 100. Specifically, the speed of the work vehicle 100 can be controlled by controlling the engine speed of the prime mover (engine) 102 and/or the gear ratio of the transmission 103. For example, the transmission 103 has multiple gear stages, and the control device 180 controls the gear ratio of the transmission 103 by switching the gear stages of the transmission 103. The multiple gear stages of the transmission 103 can be configured by combining multiple main gear stages and multiple sub gear stages. When the work vehicle 100 is being manually driven, the control device 180 controls the speed of the work vehicle 100 by controlling the prime mover 102, the braking device (brake) 293, and the transmission 103 in response to the driver's operation of an accelerator operation device 215 (e.g., an accelerator lever or accelerator pedal), a brake operation device 216 (e.g., a brake pedal), and/or a gear stage operation switch 218 (e.g., a shift lever). The gear stage operation switch 218 is a switch for selecting the gear stage of the transmission 103. The control device 180 may further switch between two-wheel drive mode and four-wheel drive mode in response to an operation by the driver.

In recording mode, the control device 180 sequentially acquires sensor data output from vehicle speed sensors such as the axle sensor 156, the engine RPM sensor 158, and the gear ratio sensor 159, which detects information about the gear ratio of the transmission 103. Based on this sensor data, the control device 180 generates and records information about the speed of the work vehicle 100, information about the engine RPM of the work vehicle 100, and information about the gear ratio of the transmission 103 as second information in association with the position information of each waypoint (first information). In such a case, in playback mode, the control device 180 controls the speed of the work vehicle 100 by controlling the prime mover 102, transmission 103, and braking device 293 included in the drive unit 240 based on the second information recorded in recording mode. The gear ratio sensor 159 may be a sensor provided on a rotating shaft within the transmission 103 that detects the gear ratio, or it may be a shift position sensor that identifies the selected gear by detecting the position of a shift lever (gear stage operation switch 218) for selecting a gear. The information on the gear ratio of the transmission 103 is not limited to information indicating the gear ratio itself, but may also be, for example, information that identifies the selected gear stage out of multiple gear stages of the transmission 103. Because one gear stage corresponds to one gear ratio, the gear ratio can be identified once the gear stage is identified.

The work vehicle 100 may be equipped with a double-speed turn function (front wheel speed increase function). A double-speed turn is an operation that increases the speed of the front wheels when the driver turns the steering wheel significantly, causing the steering angle of the front wheels to exceed a threshold. Performing a double-speed turn reduces the turning radius, enabling smoother turns. The work vehicle 100 may be equipped with a solenoid (referred to as a "double-speed solenoid") for driving a clutch that switches the double-speed turn function on and off. The control device 180 can switch the double-speed solenoid on and off via a hydraulic circuit. When the double-speed solenoid is on, the rotational speed of the front wheels is approximately twice as fast as when the double-speed solenoid is off.

The second information may further include information regarding the driving mode of the work vehicle 100. For example, the information regarding the driving mode of the work vehicle 100 may include information regarding whether the vehicle is moving forward or backward. The information regarding the driving mode may include information regarding whether the vehicle is moving in four-wheel drive mode or two-wheel drive mode. The information regarding the driving mode may include information regarding whether double speed turning is on or off. The information regarding the driving mode may further include information regarding whether automatic single braking mode is on or off. When automatic single braking mode is on, the inner rear wheel is lightly braked when the steering angle of the front wheel 104F, which is the steered wheel, exceeds a predetermined value while the vehicle is moving. In playback mode, the control device 180 controls the driving mode of the work vehicle 100 by controlling the prime mover 102, transmission 103, and brake device 293 included in the drive device 240 based on the second information recorded in recording mode.

(Steering control of work vehicle)
The control device 180 controls the steering device 106 to change the steering angle of the front wheels 104F, which are the steered wheels of the work vehicle 100, and by changing the steering angle of the steered wheels, changes the heading of the work vehicle 100. When the work vehicle 100 is being manually driven, the control device 180 changes the steering angle of the steered wheels of the work vehicle 100 and the heading of the work vehicle 100 by controlling the steering device 106 in response to operation of the steering wheel 217 by the driver.

In recording mode, the control device 180 acquires information about the steering angle of the steering wheels of the work vehicle 100 as second information based on sensor data (measured values) output from the steering wheel sensor 152 and/or the turning angle sensor 154. In such a case, in playback mode, the control device 180 controls the steering of the work vehicle 100 by controlling the hydraulic device or electric motor included in the steering device 106 based on the second information recorded in recording mode.

The second information may further include information related to the attitude of the work vehicle 100. The attitude of the work vehicle 100 is represented by, for example, a roll angle θ _R , a pitch angle θ _P , and a yaw angle θ _Y. The roll angle θ _R represents the amount of rotation about an axis in the longitudinal direction of the work vehicle 100. The pitch angle θ _P represents the amount of rotation about an axis in the lateral direction of the work vehicle 100. The yaw angle θ _Y represents the amount of rotation about an axis in the vertical direction of the work vehicle 100. The attitude may also be specified by other angles such as Euler angles, or by a quaternion. The control device 180 acquires information related to the attitude of the work vehicle 100 based on data output from the IMU 115, for example.

(When the second information includes information regarding the state of the coupling device)
12B , an example of processing performed by the control device 180 when the second information includes information related to the state of the coupling device 108 for coupling the work machine 300 will be described. Fig. 12B is a schematic diagram for explaining an example of processing performed by the control device 180 of the cruise control system 1000. In addition to the cruise control system 1000, Fig. 12B also shows the coupling device 108 and the operation switch group 210.

12B, the coupling device 108 includes a three-point hitch 291 for connecting the work machine 300 and a PTO shaft 292 for supplying rotational power to the work machine 300. The operation switch group 210 includes a 3P position switch 211 for changing the height of the three-point hitch 291 and a PTO switch 222 for switching the rotation of the PTO shaft 292 on and off. The sensor group 150 includes a 3P position sensor 251 for detecting the height position of the three-point hitch 291 and a PTO sensor 252 for detecting the rotation of the PTO shaft 292 on and off. The coupling device 108, operation switch group 210, and sensor group 150 may each include other components, but for simplicity, some components are not shown in FIG. 12B. The control device 180 is connected to the 3P position sensor 251, PTO sensor 252, three-point hitch 291, and PTO shaft 292. The control device 180 can communicate with these components using a communication protocol such as CAN.

The control device 180 controls the height of the three-point hitch 291 and the on/off switching of the rotation of the PTO shaft 292. When the work vehicle 100 is being operated manually by the driver, the control device 180 changes the height of the three-point hitch 291 in response to the driver's operation of the 3P position switch 211, and switches the rotation of the PTO shaft 292 on/off in response to the driver's operation of the PTO switch 222.

In recording mode, the control device 180 generates information regarding the height of the three-point hitch 291 as second information based on the sensor data output from the 3P position sensor 251. In such a case, in playback mode, the control device 180 controls the height of the three-point hitch 291 based on the second information recorded in recording mode. Also, in recording mode, the control device 180 acquires information regarding the on/off state of rotation of the PTO shaft 292 as second information based on the sensor data output from the PTO sensor 252. In such a case, in playback mode, the control device 180 controls the on/off state of rotation of the PTO shaft 292 based on the second information recorded in recording mode.

(When the second information includes information regarding the state of the work machine)
With reference to Figure 12C, an example of processing performed by the control device 180 when the work implement 300 is coupled to the work vehicle 100 and the second information includes information relating to the state of the work implement 300 will be described. Figure 12C is a schematic diagram for explaining an example of processing performed by the control device 180 of the cruise control system 1000. In addition to the cruise control system 1000, Figure 12C also shows the work implement 300 and the operation switch group 210. For simplicity, some components are not shown in Figure 12C.

As shown in FIG. 12C, the work machine 300 includes a drive unit 340 that performs the operations necessary for the work machine 300 to perform a predetermined task, a control device 380 that controls the operation of the drive unit 340, and one or more work machine sensors 302 that detect the state of the drive unit 340 and output sensor data. The drive unit 340 includes devices appropriate for the intended use of the work machine 300, such as a hydraulic unit, an electric motor, or a pump. The work machine sensor 302 has a structure appropriate for the drive unit 340 and includes, for example, a hydraulic sensor. The operation switch group 210 includes a work machine switch 213 for controlling the operation of the work machine 300.

The control device 180 controls the operation of the work implement 300 by sending a command to the control device 380 to control the operation of the drive device 340. When the work vehicle 100 is being operated by manual operation by the driver, the control device 180 controls the operation of the work implement 300 by sending a command to the control device 380 to control the operation of the drive device 340 in response to the driver's operation of the work implement switch 213.

In the recording mode, the control device 180 acquires or generates information regarding the state of the work machine 300 as second information based on the sensor data output from the work machine sensor 302. For example, the control device 380 may generate second information regarding the state of the work machine 300 based on the sensor data output from the work machine sensor 302 and transmit the second information to the control device 180. Alternatively, the control device 180 may receive sensor data output from the work machine sensor 302 via the control device 380 and generate information regarding the state of the work machine 300. In such a case, in the playback mode, the control device 180 controls the operation of the work machine 300 by having the control device 380 control the operation of the drive device 340 based on the second information recorded in the recording mode.

Figure 13 is a diagram showing an example of an operation terminal 200 and operation switch group 210 provided inside the cabin 105 of the work vehicle 100. Inside the cabin 105, an operation switch group 210 including a plurality of switches that can be operated by the driver is arranged. The operation switch group 210 may include the examples of operation switches described with reference to Figures 12A, 12B, and 12C.

(Stopping recording in recording mode)
Fig. 14 is a flowchart showing an example of processing performed by the control device 180 in the recording mode. As will be described below, in the example of Fig. 14, the control device 180 may cancel information on multiple waypoints in the recording mode. Explanations of matters common to the flowchart of Fig. 9A may be omitted.

As shown in FIG. 14, when the recording mode is started, in step S102, the control device 180 acquires the first information and the second information based on the position data output from the GNSS unit 110 and the sensor data output from the sensor group 150. The processing of step S102 is performed in the same manner as the processing in the example of FIG. 9A.

In step S103, the control device 180 determines whether the state of the work vehicle 100 is suitable for recording multiple waypoint information based on the position data and sensor data acquired in step S102. The determination of whether the state of the work vehicle 100 is suitable for recording multiple waypoint information is made, for example, by determining whether it has been detected that the state of the work vehicle 100 is unsuitable for recording multiple waypoint information. For example, the control device 180 determines whether the state of the work vehicle 180 satisfies a predetermined cancellation condition, and if the state of the work vehicle 180 satisfies the cancellation condition, it determines that it has been detected that the state of the work vehicle 100 is unsuitable for recording multiple waypoint information. If the state of the work vehicle 180 does not satisfy the cancellation condition, it determines that it has not been detected that the state of the work vehicle 100 is unsuitable for recording multiple waypoint information, and determines that the state of the work vehicle 100 is suitable for recording multiple waypoint information. Specific examples of cancellation conditions will be described later.

If it is determined in step S103 that the state of the work vehicle 100 is suitable for recording multiple waypoint information ("Yes" in step S103), the control device 180 performs the processing of step S104. The processing of step S104 is performed in the same manner as the processing in the example of Figure 9A. The control device 180 repeats the processing of steps S102, S103, and S104 until a command to end the recording mode is issued (step S106).

If it is detected in step S103 that the state of the work vehicle 100 is not suitable for recording multiple waypoint information ("No" in step S103), the control device 180 stops recording the multiple waypoint information in step S107. When the control device 180 stops recording the multiple waypoint information, it may display a message on a display device provided in the work vehicle 100 (e.g., a display device provided in the operation terminal 200) notifying the user that recording of the multiple waypoint information has been stopped.

14, when the control device 180 detects in recording mode that the state of the work vehicle 100 is not suitable for recording multiple waypoint information, it halts the recording of multiple waypoint information. Examples of situations in which the state of the work vehicle 100 is not suitable for recording multiple waypoint information include situations in which the state of the work vehicle 100 is not compatible with the autonomous driving performed in playback mode (e.g., a driving mode), situations in which a state or operation of the work vehicle 100 occurs that is not desirable to reproduce in playback mode, situations in which the work vehicle 100 has a malfunction or abnormality, and other situations in the work vehicle 100 that are classified as not suitable for recording multiple waypoint information. If multiple waypoint information including the first information and second information acquired when the work vehicle 100 is in such a state is recorded, for example, the reproducibility of the operation of the work vehicle 100 in playback mode may be reduced, the autonomous driving of the work vehicle 100 may not be performed smoothly in playback mode, or operations that are not desirable to reproduce from the perspective of increasing the efficiency of the repetitive operations of the work vehicle 100 may be reproduced in playback mode. In such cases, it may not be possible to sufficiently improve the efficiency of the repetitive operations of the work vehicle 100. In contrast, as shown in FIG. 14, the control device 180 halts recording of multiple waypoint information when it detects that the state of the work vehicle 100 is not suitable for recording multiple waypoint information. This improves the reproducibility of the operations of the work vehicle 100 in playback mode and enables smooth automatic driving of the work vehicle 100 in playback mode. Therefore, the efficiency of the repetitive operations of the work vehicle 100 can be improved.

Figure 15 is a flowchart showing an example of processing performed by the control device 180. The flowchart in Figure 15 shows an example of processing performed by the control device 180 when a signal including an instruction to start recording mode is received. The processing in Figure 15 can be performed in combination with the processing in Figure 14.

In step S010, the control device 180 receives a signal including an instruction to start the recording mode. For example, a signal including an instruction to start the recording mode is sent to the control device 180 by an operation by the driver.

After step S010, in step S011, the control device 180 determines whether the state of the work vehicle 100 is suitable for recording information about multiple waypoints. The determination in step S011 can be made in the same manner as the determination in step S103 in the flowchart of FIG. 14.

If it is determined in step S011 that the state of the work vehicle 100 is suitable for recording multiple waypoint information ("Yes" in step S011), the control device 180 starts the recording mode (step S100). When the recording mode starts, the process shown in the flowchart of Figure 14, for example, is performed in the recording mode.

If it is detected in step S011 that the state of the work vehicle 100 is not suitable for recording multiple waypoint information (if "No" in step S011), the control device 180 does not start the recording mode (step S090). If the control device 180 does not start the recording mode, it may display a message on a display device provided in the work vehicle 100 (e.g., a display device provided in the operation terminal 200) notifying the user that the state of the work vehicle 100 is not suitable for recording multiple waypoint information.

(Examples of cancellation conditions)
Specific examples of the stop condition are described below. As described above, the control device 180 may determine whether the state of the work vehicle 100 satisfies the stop condition when determining whether the state of the work vehicle 100 is suitable for recording a plurality of waypoint information. Specifically, the control device 180 determines whether the state of the work vehicle 100 satisfies one or more predetermined conditions, and if so, determines that the state of the work vehicle 180 satisfies the stop condition. In the recording mode, the control device 180 acquires information necessary for determining whether the state of the work vehicle 180 satisfies the stop condition based on sensor data output from the sensor group 150, and determines whether the state of the work vehicle 180 satisfies the stop condition based on the acquired information. The information acquired by the control device 180 as information necessary for determining whether the state of the work vehicle 180 satisfies the stop condition may or may not be recorded as second information of the waypoint information (i.e., necessary information separate from the second information may be acquired based on sensor data). Below, specific examples of the stop condition are described, along with examples of processing performed by the control device 180. Any one or more of the following specific examples may be used in combination.

(1) The speed of the work vehicle 100 is greater than a predetermined value. For example, the cancellation condition may include "the speed of the work vehicle 100 is greater than a predetermined value." If the speed of the work vehicle 100 is too fast, it may not be possible to reproduce the work vehicle 100 during automated driving in playback mode, or it may not be desirable to reproduce the work vehicle 100 in playback mode. By canceling the recording of multiple waypoint information when the speed of the work vehicle 100 is too fast, the reproducibility of the work vehicle 100's operation in playback mode can be improved. As described with reference to FIG. 10 , in recording mode, the control device 180 acquires one or more of information on the speed of the work vehicle 100, information on the engine speed of the work vehicle 100, and information on the gear ratio of the transmission 103 based on sensor data output from a vehicle speed sensor such as the axle sensor 156 and a gear ratio sensor 159 that detects information on the gear ratio of the transmission 103. The control device 180 may acquire information on the speed of the work vehicle 100 based on sensor data output from the IMU 115. Based on the acquired information, the control device 180 determines whether the speed of the work vehicle 100 is greater than a predetermined value. The control device 180 may acquire information on the speed of the work vehicle 100 by acquiring information on the rate of change per unit time of the position of the work vehicle 100 based on the position data output from the positioning device 110. The condition that the speed of the work vehicle 100 is greater than a predetermined value can also be expressed as the rate of change per unit time of the position of the work vehicle 100 being greater than a predetermined value.

(2) The acceleration of the work vehicle 100 is greater than a predetermined value. The stop condition may include "the acceleration of the work vehicle 100 is greater than a predetermined value." Acceleration is the rate of change of speed per unit time. Sudden acceleration or deceleration (e.g., sudden braking) of the work vehicle 100 may not be reproducible during automated driving in playback mode, or it may not be desirable to reproduce the event in playback mode. Therefore, by stopping the recording of multiple waypoint information when it is detected that the acceleration of the work vehicle 100 is too high, the reproducibility of the operation of the work vehicle 100 in playback mode can be improved. As in the case of (1) above, the control device 180 acquires one or more of information on the speed of the work vehicle 100, information on the acceleration of the work vehicle 100, information on the engine rotation speed of the work vehicle 100, and information on the gear ratio of the transmission 103 based on sensor data output from the vehicle speed sensors such as the axle sensor 156, the gear ratio sensor 159 that detects information on the gear ratio of the transmission 103, and the IMU 115. Based on the acquired information, the control device 180 determines whether the speed of the work vehicle 100 is greater than a predetermined value.

(3) The tilt angle of the work vehicle 100 is greater than a predetermined value, and the rate of change of the tilt angle of the work vehicle 100 per unit time is greater than a predetermined value.
The cancellation conditions may include "the inclination angle of the work vehicle 100 is greater than a predetermined value" and/or "the rate of change of the inclination angle of the work vehicle 100 per unit time is greater than a predetermined value." A state in which the inclination angle of the work vehicle 100 or its rate of change is too large is not preferably reproduced in playback mode. By canceling the recording of multiple waypoint information when the inclination angle of the work vehicle 100 or its rate of change is too large, the reproducibility of the operation of the work vehicle 100 in playback mode can be improved. The control device 180 acquires information about the attitude of the work vehicle 100 based on the sensor data output from the IMU 115, and determines, based on the acquired information, whether the inclination angle of the work vehicle 100 and/or its rate of change per unit time is greater than a predetermined value.

(4) The steering angle of the steering wheels of the work vehicle 100 is greater than a predetermined value, and the rate of change per unit time of the steering angle of the steering wheels of the work vehicle 100 is greater than a predetermined value. The stop conditions can include "the steering angle of the steering wheels of the work vehicle 100 is greater than a predetermined value" and/or "the rate of change per unit time of the steering angle of the steering wheels of the work vehicle 100 is greater than a predetermined value." A state in which the steering angle is too large is equivalent to a state in which the steering wheel is turned sharply, and a state in which the rate of change of the steering angle is too large is equivalent to a state in which the steering wheel is turned suddenly. Since it is not desirable to reproduce these states in playback mode, by stopping the recording of multiple waypoint information when such states are detected, the reproducibility of the operation of the work vehicle 100 in playback mode can be improved. As described with reference to FIG. 10 , in the recording mode, the control device 180 acquires information about the steering angle of the steering wheels of the work vehicle 100 based on the sensor data (measured values) output from the steering wheel sensor 152 and/or the turning angle sensor 154, and determines, based on the acquired information, whether the steering angle of the steering wheels of the work vehicle 100 and/or its rate of change per unit time is greater than a predetermined value.

(5) The fuel level of the work vehicle 100 is less than a predetermined level, the battery voltage of the work vehicle 100 is lower than a predetermined value, or a malfunction of the work vehicle 100 is detected. The abort conditions may include "the fuel level of the work vehicle 100 is less than a predetermined level,""the battery voltage of the work vehicle 100 is lower than a predetermined value," and/or "a malfunction of the work vehicle 100 is detected." Such a state is not suitable for traveling to record multiple waypoint information. The control device 180 acquires information on the remaining fuel level from sensor data output from the fuel sensor and determines whether the fuel level of the work vehicle 100 is less than a predetermined level based on the acquired information. The control device 180 acquires information on the battery voltage from sensor data output from the battery voltage sensor and determines whether the battery voltage of the work vehicle 100 is lower than a predetermined value based on the acquired information. The control device 180 can detect other malfunctions (i.e., conditions that are considered abnormal for the work vehicle 100) based on the sensor data output from the sensor group 150.

(6) Satellite Signal Reception Interference by the Positioning Device 110 The cancellation condition may include "satellite signal reception interference by the positioning device 110.""Satellite signal reception interference" refers to a state in which the reliability of positioning is reduced compared to normal due to poor satellite signal reception. In such a state, the reliability of the position data output by the positioning device 110 may be reduced, making it unsuitable for driving to record multiple waypoint information. Reception interference may occur, for example, when the number of detected satellites is small (e.g., three or fewer), when the reception strength of each satellite signal is low, or when multipath interference occurs. The control device 180 can determine whether reception interference is occurring based on, for example, information about satellites included in the GNSS data. For example, the presence or absence of reception interference can be determined based on the reception strength value for each satellite included in the GNSS data or the DOP (Dilution of Precision) value, which indicates the satellite's positioning status.

(7) The driver's seat of the work vehicle 100 is detected to be vacant. The stop condition may include "the driver's seat of the work vehicle 100 is detected to be vacant." If the driver is temporarily away from the driver's seat 107 (see FIG. 1 ) of the work vehicle 100 or is not properly seated in the driver's seat 107, recording of multiple waypoint information is stopped. For example, this stop condition may be applied when manual driving is being performed by the driver of the work vehicle 100 in the recording mode. This stop condition may also be applied when, while performing automatic driving in the recording mode, driving is partially based on manual operation by the driver of the work vehicle 100. The control device 180 determines whether the driver's seat 107 is vacant based on sensor data output from a seat switch attached to the driver's seat 107 of the work vehicle 100. The seat switch can detect whether the driver's seat 107 is vacant by detecting the load on the seat surface of the driver's seat 107.

(8) Wheel slippage of the work vehicle 100 is detected, or dashing of the work vehicle 100 is detected. The stop conditions may include "wheel slippage of the work vehicle 100 is detected" and/or "dashing of the work vehicle is detected." Slippage and dashing are not preferably reproduced in playback mode. Dashing is a phenomenon that can occur when a rotary is coupled to the work vehicle 100 as the work implement 300. When the rotary's tiller tines come into contact with a hard surface and do not penetrate deep into the soil, the work vehicle 100 is suddenly pushed forward by the rotation of the tiller tines. The control device 180 acquires information on the speed and acceleration of the work vehicle 100 based on sensor data output from vehicle speed sensors such as the axle sensor 156 and the IMU 115, and can detect slippage or dashing of the work vehicle 100 based on the acquired information.

(9) The driving mode of the work vehicle 100 is changed to a driving mode that does not support autonomous driving, or the transmission 103 of the work vehicle 100 is changed to a gear that does not support autonomous driving. The stop condition may include "the driving mode of the work vehicle 100 is changed to a driving mode that does not support autonomous driving" and/or "the transmission 103 of the work vehicle 100 is changed to a gear that does not support autonomous driving." These conditions may apply when manual driving is being performed in recording mode. For example, if the driving modes of the work vehicle 100 have a four-wheel drive mode and a two-wheel drive mode, and the four-wheel drive mode is compatible with autonomous driving and the two-wheel drive mode is not compatible with autonomous driving, when the driving mode is changed from the four-wheel drive mode to the two-wheel drive mode in recording mode, the control device 180 stops recording the multiple waypoint information. Furthermore, if the reverse drive of the work vehicle 100 is not compatible with autonomous driving, when the driving mode is switched from forward drive to reverse drive in recording mode, the control device 180 stops recording the multiple waypoint information. Furthermore, when one of the multiple gear stages of the transmission 103 is changed to a gear stage that does not support autonomous driving, the control device 180 stops recording the multiple waypoint information. The control device 180 can, for example, acquire information related to the driving mode of the work vehicle 100 from the transmission 103, and detect, based on the acquired information, that the driving mode has been changed to a mode that does not support autonomous driving, and that one of the multiple gear stages of the transmission 103 has been changed to a gear stage that does not support autonomous driving.

(10) A predetermined condition related to DPF (Diesel Particulate Filter) regeneration of the exhaust device 232 of the work vehicle 100 has been satisfied, and an abnormality in the SCR system of the exhaust device 232 of the work vehicle 100 has been detected. The stop condition may include "a predetermined condition related to DPF regeneration of the work vehicle 100 has been satisfied." For example, as described below, it includes "the amount of particulate matter trapped by the DPF 212a of the work vehicle 100 is greater than a predetermined value." An example of processing performed by the control device 180 will be described with reference to FIG. 16 .

As shown in FIG. 16 , the work vehicle 100 is equipped with an exhaust system 232 that discharges exhaust gas from the prime mover 102 (e.g., a diesel engine) to the outside. The exhaust system 232 is provided with a DPF 232a that captures particulate matter (PM) in the exhaust gas. When the amount of particulate matter captured in the DPF 232a exceeds a specified amount, "DPF regeneration" is performed to reduce the particulate matter in the DPF 232a and restore the DPF 232a's capturing capacity. For example, the particulate matter in the DPF 232a can be reduced by increasing the temperature of the exhaust gas from the engine 102 or by mixing fuel with the exhaust gas. The control device 180 acquires information on the amount of particulate matter captured by the PF 232a based on sensor data output from a PM sensor 234 that detects the amount of particulate matter captured by the DPF 212a.

The stop condition may include "detection of an abnormality in the SCR system of the exhaust device 232 of the work vehicle 100." As shown in FIG. 16 , the exhaust device 232 is further provided with a nitrogen oxide reduction device 232b that reduces nitrogen oxides (NO _x ) in the exhaust gas. The nitrogen oxide reduction device 232b is sometimes called an SCR (Selective Catalytic Reduction) system 232b, and reduces nitrogen oxides by using urea water as a reducing agent. The control device 180 can detect an abnormality in the SCR system 232b. For example, it can detect an insufficient amount of urea water, frozen urea water, or impurities being mixed into the urea water based on data output from a sensor (e.g., level sensor 236) attached to the urea water tank 232c.

(11) The two brake pedals of the work vehicle 100 are released from the connection The cancellation condition can include "the two brake pedals of the work vehicle 100 are released from the connection." FIG. 17 is a diagram showing an example of a brake operating device 216 provided inside the cabin 105 of the work vehicle 100. As shown in FIG. 17, the work vehicle 100 is equipped with two brake pedals 216a and 216b. The two brake pedals 216a and 216b can be switched between a state in which they are coupled to each other and a state in which they are released from the connection by a coupling device 216c. In the figure, the position of the coupling device 216c when the two brake pedals 216a and 216b are coupled to each other is shown by a solid line, and the reference number for the coupling device 216c has a suffix "(1)" added. The position of the coupling device 216c when the two brake pedals 216a and 216b are released from the coupling is shown by a dotted line, and the reference number of the coupling device 216c is suffixed with "(2)".

When the two brake pedals 216a and 216b are uncoupled, they can independently operate the braking control devices that control the axles that rotate the left and right rear wheels 104R. If the operation of the two brake pedals 216a and 216b when they are uncoupled cannot be handled by the control in playback mode, the two brake pedals 216a and 216b can stop recording multiple waypoint information when they are uncoupled. The control device 180 can detect that the two brake pedals 216a and 216b have been uncoupled based on data output from a sensor that detects the position of the coupling device 216c.

(12) The time and/or distance traveled while recording a plurality of waypoint information is greater than a predetermined value, and the data volume of the plurality of waypoint information recorded in the storage device is greater than a predetermined value. The abort condition may include "the time and/or distance traveled while recording a plurality of waypoint information is greater than a predetermined value" and/or "the data volume of the plurality of waypoint information recorded in the storage device 870 is greater than a predetermined value." The control device 180 determines whether the above abort condition is met based on information regarding the data volume of the plurality of waypoint information stored in the storage device 870, which is obtained from the storage device 870.

(Limitation on changing the state of the work vehicle in recording mode)
As in the example shown in Fig. 14 , if the recording of multiple waypoint information is stopped during the recording mode, it may be necessary to restart driving in the recording mode from the beginning in order to record the multiple waypoint information. In contrast, the example of Fig. 18 makes it possible to prevent the recording of multiple waypoint information from being stopped in the recording mode. Fig. 18 is a flowchart showing an example of processing performed by the control device 180 when a user (e.g., the driver) performs an operation to change the state of the work vehicle 100 in the recording mode. The processing of the flowchart in Fig. 18 can be performed at any timing in the recording mode, and is performed in combination with any of the example flowcharts performed in the recording mode described above, for example.

In recording mode, in step S112, the control device 180 receives a signal including an instruction to change the state of the work vehicle 100. When a user (e.g., the driver) performs an operation to change the state of the work vehicle 100, a signal including an instruction to change the state of the work vehicle 100 is transmitted to the control device 180 in response to the user's operation.

In step S114, the control device 180 determines whether the state of the work vehicle 100 as assumed to have been changed based on the instructions received in step S112 (hereinafter sometimes referred to as the "assumed changed vehicle state") is suitable for recording multiple waypoint information. The determination in step S114 is made before the state of the work vehicle 100 is actually changed based on the received instructions.

The determination of whether the assumed changed vehicle state is suitable for recording multiple waypoint information is made, for example, by determining whether the assumed changed vehicle state satisfies a predetermined cancellation condition. For example, if the assumed changed vehicle state satisfies the cancellation condition, the control device 180 determines that the assumed changed vehicle state is not suitable for recording multiple waypoint information. If the assumed changed vehicle state does not satisfy the cancellation condition, the control device 180 determines that the assumed changed vehicle state is suitable for recording multiple waypoint information. The cancellation conditions described above can be used as cancellation conditions. Typically, of the cancellation conditions (1) to (12) exemplified above, a condition that may be satisfied due to a change in the state of the work vehicle 100 caused by user operation is applied. The control device 180 acquires the information necessary for the determination in the same manner as described above, and determines whether the cancellation condition is satisfied based on the acquired information.

If it is determined in step S114 that the assumed changed vehicle state is suitable for recording multiple waypoint information ("Yes" in step S114), the control device 180 changes the state of the work vehicle 100 in step S116 based on the instruction received in step S112.

If it is determined in step S114 that the assumed changed vehicle state is not suitable for recording multiple waypoint information ("No" in step S114), the control device 180 in step S118 restricts changes to the state of the work vehicle 100 based on the instructions received in step S112. When the control device 180 "restricts changes to the state of the work vehicle 100," this not only means prohibiting changes to the state of the work vehicle 100, i.e., maintaining the state of the work vehicle 100 without any changes, but also includes changing the state of the work vehicle 100 by reflecting the received instructions only to the extent that the cancellation condition is not met. For example, if the cancellation condition includes the speed of the work vehicle 100 being greater than a predetermined value (e.g., 10 km/h), and the instruction received when the speed of the work vehicle 100 is 5 km/h includes an instruction to change the speed of the work vehicle 100 to 20 km/h, the control device 180 may maintain the speed of the work vehicle 100 at its current speed (5 km/h) or may change the speed so that the speed of the work vehicle 100 is equal to or less than the predetermined value (10 km/h or less in this example).

In the example of FIG. 18 , when a user performs an operation to change the state of the work vehicle 100 in recording mode, the control device 180 can limit changes to the vehicle state based on the user's operation so that the changed state of the work vehicle 100 is suitable for recording multiple waypoint information. This not only improves the reproducibility of the operation of the work vehicle 100 in playback mode and enables smooth autonomous driving of the work vehicle 100 in playback mode, but also reduces the possibility that recording of multiple waypoint information will be stopped during recording mode. This solves the problem of having to restart driving in recording mode from the beginning if recording of multiple waypoint information is stopped during recording mode, thereby improving user convenience.

A specific example of the flowchart in Figure 18 will be described with reference to Figures 19A to 19C. Figures 19A to 19C are flowcharts showing an example of processing performed by the control device 180 when a user (e.g., the driver) performs an operation to change the state of the work vehicle 100 in recording mode.

As shown in FIG. 19A, in recording mode, in step S112a, the control device 180 receives a signal including an instruction to change the engine speed of the work vehicle 100 and/or the gear ratio of the transmission 103. When a user (e.g., the driver) performs an operation to change the speed of the work vehicle 100, a signal including an instruction to change the engine speed of the work vehicle 100 and/or the gear ratio of the transmission 103 is transmitted to the control device 180 in response to the user's operation.

In step S114a, the control device 180 determines whether the speed of the work vehicle 100, assumed to have been changed based on the instruction received in step S112a (hereinafter sometimes referred to as the "assumed changed speed"), is suitable for recording multiple waypoint information. The determination in step S114a is made before the speed of the work vehicle 100 is actually changed based on the received instruction. The determination of whether the assumed changed speed is suitable for recording multiple waypoint information is made, for example, by determining whether the assumed changed speed satisfies a cancellation condition. In this example, the cancellation condition includes the speed of the work vehicle 100 being greater than a predetermined value. Therefore, in step S114a, the control device 180 determines whether the assumed changed speed is equal to or less than a predetermined value.

If it is determined in step S114a that the assumed changed speed is equal to or less than the predetermined value ("Yes" in step S114a), the control device 180 changes the speed of the work vehicle 100 in step S116a by changing the engine speed of the work vehicle 100 and/or the gear ratio of the transmission 103 based on the instruction received in step S112a.

If it is determined in step S114a that the assumed changed speed is greater than the predetermined value ("No" in step S114a), the control device 180 in step S118a restricts the change in the speed of the work vehicle 100 based on the instruction received in step S112a. Here, the control device 180 sets the speed of the work vehicle 100 to a predetermined value or less. For example, the control device 180 may maintain the speed of the work vehicle 100 unchanged, or may change the speed of the work vehicle 100 within a range below the predetermined value.

In the example of FIG. 19B, in recording mode, in step S112b, the control device 180 receives a signal including an instruction to change the steering angle of the steering wheels of the work vehicle 100. When a user (e.g., the driver) performs an operation to change the steering angle of the steering wheels of the work vehicle 100, a signal including an instruction to change the steering angle of the steering wheels of the work vehicle 100 is transmitted to the control device 180 in response to the user's operation.

In step S114b, the control device 180 determines whether the steering angle of the steering wheels of the work vehicle 100, assumed to have been changed based on the instruction received in step S112b (hereinafter referred to as the "assumed changed steering angle"), is suitable for recording multiple waypoint information. The determination in step S114b is made before the steering angle of the work vehicle 100 is actually changed based on the received instruction. The determination of whether the assumed changed steering angle is suitable for recording multiple waypoint information is made, for example, by determining whether the assumed changed steering angle satisfies a cancellation condition. In this example, the cancellation condition includes the steering angle of the steering wheels of the work vehicle 100 being greater than a predetermined value. Therefore, in step S114b, the control device 180 determines whether the assumed changed steering angle is equal to or less than a predetermined value. Note that the cancellation condition may further include the rate of change per unit time of the steering angle of the steering wheels of the work vehicle 100 being greater than a predetermined value. In this case, the following processing can be performed in the same way.

If it is determined in step S114b that the assumed changed steering angle is equal to or less than the predetermined value ("Yes" in step S114b), the control device 180 changes the steering angle of the steered wheels of the work vehicle 100 in step S116b based on the instruction received in step S112b.

If it is determined in step S114b that the assumed changed steering angle is greater than the predetermined value ("No" in step S114b), the control device 180 in step S118b limits the change in speed of the work vehicle 100 based on the instruction received in step S112b. Here, the control device 180 sets the steering angle of the work vehicle 100 to a predetermined value or less. For example, the control device 180 may maintain the steering angle of the work vehicle 100 unchanged, or may change the steering angle of the work vehicle 100 within a range less than the predetermined value.

In the example of FIG. 19C, in recording mode, the control device 180 receives a signal including an instruction to change the driving mode of the work vehicle 100 in step S112c. When a user (e.g., the driver) performs an operation to change the driving mode of the work vehicle 100, a signal including an instruction to change the driving mode of the work vehicle 100 is transmitted to the control device 180 in response to the user's operation.

In step S114c, the control device 180 determines whether the driving mode of the work vehicle 100, assumed to have been changed based on the instruction received in step S112c (hereinafter sometimes referred to as the "assumed changed driving mode"), is suitable for recording multiple waypoint information. The determination in step S114c is made before the driving mode of the work vehicle 100 is actually changed based on the received instruction. The determination of whether the assumed changed driving mode is suitable for recording multiple waypoint information is made, for example, by determining whether the assumed changed driving mode satisfies a cancellation condition. In this example, the cancellation condition includes the driving mode of the work vehicle 100 being changed to a driving mode that is not compatible with autonomous driving. Therefore, in step S114c, the control device 180 determines whether the assumed changed driving mode is compatible with autonomous driving.

If it is determined in step S114c that the assumed changed driving mode is compatible with autonomous driving ("Yes" in step S114c), the control device 180 changes the driving mode of the work vehicle 100 in step S116c based on the instruction received in step S112c. For example, if the driving modes of the work vehicle 100 include a four-wheel drive mode and a two-wheel drive mode, and the four-wheel drive mode is compatible with autonomous driving and the two-wheel drive mode is not compatible with autonomous driving, when the control device 180 receives an instruction to change from the two-wheel drive mode to the four-wheel drive mode in the recording mode, the control device 180 changes the driving mode of the work vehicle 100 from the two-wheel drive mode to the four-wheel drive mode.

If it is determined in step S114c that the assumed changed driving mode is greater than the predetermined value ("No" in step S114c), the control device 180 prohibits in step S118c changing the driving mode of the work vehicle 100 based on the instruction received in step S112b. That is, the control device 180 maintains the driving mode of the work vehicle 100. For example, if the driving modes of the work vehicle 100 include a four-wheel drive mode and a two-wheel drive mode, and the four-wheel drive mode is compatible with autonomous driving and the two-wheel drive mode is not compatible with autonomous driving, when the control device 180 receives an instruction to change from four-wheel drive mode to two-wheel drive mode in recording mode, the control device 180 maintains the driving mode of the work vehicle 100 in four-wheel drive mode.

The processing performed by the control device of the cruise control system according to the embodiment of the present disclosure is not limited to the specific example described above. For example, the cancellation conditions described above are merely examples, and other conditions may also be applied.

The cruise control systems in the above embodiments can also be retrofitted to work vehicles that do not have these functions. Such control systems can be manufactured and sold independently of the work vehicle. The computer programs used in such control systems can also be manufactured and sold independently of the work vehicle. The computer programs can be provided, for example, by being stored on a computer-readable, non-transitory storage medium. The computer programs can also be provided by downloading via a telecommunications line (e.g., the Internet).

The technology disclosed herein has broad application to various types of work vehicles used in smart agriculture.

100: Work vehicle, 110: Positioning device (GNSS unit), 150: Sensor group, 180: Control device, 210: Operation switch group, 300: Implement (work machine), 1000: Travel control system

Claims (21)

A travel control system for a work vehicle,
a positioning device that detects the position of the work vehicle and outputs position data;
one or more sensors that detect the state of the work vehicle and output sensor data;
a control device for controlling the operation of the work vehicle,
The control device
capable of operating in record and play modes;
In the recording mode, while the work vehicle is traveling, based on the position data and the sensor data, a plurality of waypoint information pieces each including first information on the position of the work vehicle and second information on the state of the work vehicle are recorded in a storage device;
In the playback mode, the operation of the work vehicle is controlled while the work vehicle is traveling by automatic driving based on the first information and the second information included in the plurality of waypoint information recorded in the recording mode;
A driving control system that, in the recording mode, stops recording the plurality of waypoint information if it is detected based on the position data and/or the sensor data that the state of the work vehicle is not suitable for recording the plurality of waypoint information. The control device
The cruise control system according to claim 1 , wherein in the recording mode, if the state of the work vehicle satisfies a predetermined stopping condition based on the position data and/or the sensor data, recording of the plurality of waypoint information is stopped. The termination condition is:
the speed of the work vehicle is greater than a predetermined value;
the acceleration of the work vehicle is greater than a predetermined value; and the tilt angle of the work vehicle is greater than a predetermined value.
Including those who fall under any of the following:
The control device
3. The driving control system according to claim 2, wherein in the recording mode, it is determined whether or not the cancellation condition is met based on information on the speed of the work vehicle, information on the acceleration of the work vehicle, information on the inclination angle of the work vehicle, information on the engine rotation speed of the work vehicle, and information on the gear ratio of the transmission of the work vehicle, all of which are acquired from the position data and/or the sensor data. The termination condition is:
a steering angle of a steering wheel of the work vehicle being greater than a predetermined value,
The control device
4. The cruise control system according to claim 2, wherein in the recording mode, it is determined whether the cancellation condition is met based on the steering angle information acquired from the sensor data. The termination condition is:
a rate of change per unit time of the steering angle of the steering wheels of the work vehicle being greater than a predetermined value,
The control device
4. The cruise control system according to claim 2, wherein in the recording mode, it is determined whether the cancellation condition is met based on the steering angle information acquired from the sensor data. The termination condition is:
the work vehicle has less fuel than a predetermined amount;
The control device
4. The cruise control system according to claim 2, wherein in the recording mode, it is determined whether the cancellation condition is met based on information about the remaining amount of fuel obtained from the sensor data. The termination condition is:
The positioning device is experiencing a reception failure of a satellite signal,
The control device
4. The cruise control system according to claim 2, wherein in the recording mode, it is determined whether the cancellation condition is met based on information about satellites included in the data output from the positioning device. The termination condition is:
a data volume of the plurality of waypoint information stored in the storage device is greater than a predetermined value;
The control device
4. The cruise control system according to claim 2, wherein in the recording mode, it is determined whether the cancellation condition is met based on information regarding the data capacity of the plurality of waypoint information stored in the storage device, the information being acquired from the storage device. The termination condition is:
the speed of the work vehicle is greater than a predetermined value;
the acceleration of the work vehicle is greater than a predetermined value;
the tilt angle of the work vehicle is greater than a predetermined value;
The rate of change per unit time of the tilt angle of the work vehicle is greater than a predetermined value;
The steering angle of the steering wheels of the work vehicle is greater than a predetermined value;
a rate of change per unit time of the steering angle of the steering wheels of the work vehicle is greater than a predetermined value;
The rate of change of the position of the work vehicle per unit time is greater than a predetermined value;
Wheel slippage of the work vehicle is detected;
that dashing of the work vehicle is detected;
the work vehicle has less fuel than a predetermined amount;
the battery voltage of the work vehicle is lower than a predetermined value;
The positioning device is experiencing interference with satellite signals;
A malfunction of the work vehicle has been detected;
It is detected that the driver's seat of the work vehicle is vacant;
The driving mode of the work vehicle has been changed to one that is not compatible with automatic driving.
The transmission of the work vehicle has been changed to a gear that is not compatible with autonomous driving,
The two brake pedals of the work vehicle are disconnected;
A predetermined condition regarding DPF regeneration of the work vehicle is satisfied;
A predetermined condition related to the SCR system of the work vehicle is satisfied;
4. The cruise control system according to claim 2 or 3, wherein the time and/or distance traveled while recording the plurality of waypoint information is greater than a predetermined value, and the data capacity of the plurality of waypoint information recorded in the storage device is greater than a predetermined value. The control device
4. The driving control system according to claim 2, wherein when a signal including an instruction to start the recording mode is received, if the state of the work vehicle satisfies the cancellation condition, the recording mode is not started. The control device
4. The cruise control system according to claim 1, wherein, when recording of the plurality of waypoint information is stopped in the recording mode, a display device provided in the work vehicle displays a message notifying a user that recording of the plurality of waypoint information has been stopped. The cruise control system of any one of claims 1 to 3, wherein the second information includes at least one of information on the speed of the work vehicle, information on the engine speed of the work vehicle, information on the gear ratio of the transmission of the work vehicle, and information on the attitude of the work vehicle. A work machine is connected to the work vehicle,
the second information includes information regarding the operation of the work machine,
The control device
The travel control system according to claim 1 , wherein, in the playback mode, the operation of the work machine is controlled based on the second information included in the plurality of waypoint information recorded in the recording mode. The driving control system described in claim 13, wherein, in the recording mode, the work vehicle travels while performing work using the work equipment. The travel control system described in claim 13, wherein, in the recording mode, the work vehicle travels between multiple crop rows while performing work using the work implement. The work vehicle has a coupling device for connecting the work implement,
The cruise control system of claim 13 , wherein the second information includes information regarding a state of the coupling device. The coupling device includes a three-point hitch for adjusting the height of the work machine,
17. The cruise control system of claim 16, wherein the information regarding the status of the hitch includes information about the height of the three-point hitch. the coupling device includes a PTO shaft that supplies power to the work machine,
17. The cruise control system of claim 16, wherein the information regarding the state of the coupling device includes whether the PTO shaft is rotating on or off. The cruise control system according to any one of claims 1 to 3;
a running device including a steering wheel;
a first drive device that drives the traveling device,
In the playback mode, the control device controls the first drive device based on the first information and the second information included in the plurality of waypoint information recorded in the recording mode, thereby causing the work vehicle to travel in an automatic driving manner. a work machine coupled to the work vehicle;
a second drive device that drives the work machine,
the second information includes information regarding the operation of the work machine,
20. The work vehicle according to claim 19, wherein in the playback mode, the control device controls the operation of the work implement by controlling the second drive device based on the second information included in the plurality of waypoint information recorded in the recording mode. A work vehicle travel control method executed by a control device that controls the operation of a work vehicle and is capable of operating in a recording mode and a playback mode, comprising:
In the recording mode, while the work vehicle is traveling, recording a plurality of waypoint information in a storage device, each of which includes first information regarding the position of the work vehicle and second information regarding the state of the work vehicle, based on position data acquired from a positioning device that detects the position of the work vehicle and sensor data acquired from one or more sensors that detect the state of the work vehicle;
In the playback mode, controlling the operation of the work vehicle while causing the work vehicle to travel by automatic driving based on the first information and the second information included in the plurality of waypoint information recorded in the recording mode;
A driving control method that includes, in the recording mode, if it is detected based on the position data and/or the sensor data that the state of the work vehicle is not suitable for recording the plurality of waypoint information, stopping the recording of the plurality of waypoint information.