JP2019011007A - Vehicle control apparatus and vehicle control method - Google Patents

Abstract

To provide a vehicle control device and a vehicle control method for preventing delay of vehicle control on the basis of determination result of road surface classification and capable of performing proper control according to a road surface.SOLUTION: A road surface classification determination part determines road surface classification on the basis of road surface detection data of one or a plurality of regions from among road surface detection data detected by a sensor for each of a plurality of regions at a front of the vehicle. A region used for determination is set to be variable according to vehicle speed.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicle control device and a vehicle control method.

  Patent Document 1 detects the road surface condition of the road on which the vehicle travels, for example, a low μ road by optical image recognition means, and controls the oil pressure according to the friction coefficient μ. Since it can be controlled, it is disclosed that the fuel efficiency is improved and the driving performance is improved by controlling the gear position (including the gear ratio).

Japanese Patent Laid-Open No. 03-204465

  However, the friction coefficient μ of the road surface (in other words, asphalt road surface, concrete road surface, block road surface, gravel road surface) is measured using a laser lidar-like sensor that can detect an object using laser light and measure the distance to the object. If it is detected, it takes time to detect the reflection of light, process the image, and determine the type of road surface ahead. When the vehicle is traveling at high speed, the actual road surface On the other hand, the road surface may not be judged in time.

  The object of the present invention is made in view of such a technical problem, and it is possible to prevent a delay in vehicle control by determining a road surface type using road surface detection data in an appropriate front area according to the vehicle speed. Then, it is providing the vehicle control apparatus and vehicle control method which can perform suitable control according to road surface classification.

  A vehicle control device and a vehicle control method, wherein a road surface type determination unit is configured to determine a road surface type based on road surface detection data of one or more areas among road surface detection data for each of a plurality of areas in front of the vehicle detected by a sensor. The region used for the determination is made variable depending on the vehicle speed.

  By making it possible to select the area of road surface detection data used for road surface type determination according to the vehicle speed, the processing time for road surface type determination is shortened when traveling at high vehicle speeds, and the road surface type determination accuracy is improved when traveling at low vehicle speeds. Vehicle control can be performed.

It is a figure which shows schematic structure of the vehicle control apparatus which concerns on this invention. FIG. 3 is a schematic diagram illustrating a road surface detection area in front of a vehicle by a sensor according to a first embodiment. BRIEF DESCRIPTION OF THE DRAWINGS (a) Side surface sectional drawing and (b) Top view for demonstrating the sensor which concerns on Example 1. FIG. 6 is a flowchart illustrating the contents of road surface state determination processing in a road surface type determination unit according to the first embodiment. It is a table which shows the relationship between the vehicle speed in the road surface classification determination part which concerns on Example 1, and the use area | region of road surface detection data. 5 is a flowchart showing the contents of processing of a road surface type determination unit according to the first embodiment. FIG. 3 is a schematic hydraulic characteristic diagram of the continuously variable transmission according to the road surface type according to the first embodiment. 3 is a time chart showing a change in hydraulic pressure of the continuously variable transmission during vehicle control of the vehicle control device according to the first embodiment. FIG. 10 is a schematic gear ratio characteristic diagram of the continuously variable transmission at a predetermined throttle opening degree according to a road surface type according to the second embodiment. 6 is a time chart showing a change in a gear ratio of a continuously variable transmission during vehicle control of a vehicle control device according to a second embodiment. 12 is a flowchart showing the contents of processing of a road surface type determination unit according to a third embodiment. FIG. 10 is a schematic output characteristic diagram of an engine according to a road surface type according to a third embodiment. 12 is a time chart showing changes in engine output during vehicle control of the vehicle control device according to the third embodiment. 10 is a flowchart showing the contents of processing by a road surface type determination unit according to a fourth embodiment. FIG. 10 is a schematic diagram of brake pressure characteristics according to road surface types according to a fourth embodiment. It is a time chart which shows the change of the brake pressure at the time of vehicle control of the vehicle control device concerning Example 4.

[Example 1]
FIG. 1 is a diagram showing a schematic configuration of a vehicle control device according to the present invention.
This vehicle includes an engine 1 as a power source. The output rotation of the engine 1 is simply "the continuously variable transmission 4" by combining the torque converter 2 with the lock-up clutch, the first gear train 3, the variator 20, and the auxiliary transmission 30 (hereinafter, the variator 20 and the auxiliary transmission 30 together). Is transmitted to the drive wheel 7 via the second gear train 5 and the final reduction gear 6. The second gear train 5 is provided with a parking mechanism 8 that mechanically locks the output shaft of the transmission 4 at the time of parking.

The vehicle has an engine controller 1 a that controls the engine 1 as a vehicle control unit, an oil pump 10 that is driven by using a part of the power of the engine 1, and a hydraulic pressure from the oil pump 10 that is adjusted to change the speed. A transmission controller 12 as a control device for controlling the hydraulic control circuit 11 supplied to each part of the machine 4 and a brake controller 100 as a control device for controlling the brake pressure supplied to the wheel cylinder according to the brake pedal depression force. Is provided.
Further, an accelerator opening (throttle opening) sensor 41, a primary input rotation speed sensor 42, a vehicle speed sensor 43, a hydraulic pressure sensor 44 of the continuously variable transmission 4, a select lever position sensor 45 operated by the driver, and the like are provided. . These sensors are connected to various controllers and the road surface type determination unit 50 via an appropriate bus such as a CAN (Controller Area Network) or a high-speed communication bus, and can share information with each other.

The road surface type determination unit (ADAS) 50 outputs road surface type information to the engine controller 1a, the transmission controller 12, and the brake controller 100.
Each of the controllers 1a, 12, 100 has characteristics suitable for the road surface type. Details will be described later.
The road surface type determination unit (ADAS) 50 obtains road surface detection data from a sensor (Laser LIDAR) 60 that irradiates the road surface ahead of the vehicle with laser light and receives the reflected laser light, and uses the road surface detection data from the road surface detection data. The road surface type is determined. The angle of light emitted from the sensor 60 is adjusted by an angle adjustment actuator 61. The angle adjustment actuator 61 adjusts the angle of light emitted by the sensor 60 in order to change the number and position of the vehicle front area from which road surface data is acquired. Details will be described later.

  Further, the road surface type determination unit (ADAS) 50 determines whether or not the road surface is wet based on the wiper 71, the vibration sensor 72 installed on the windshield, or information 73 such as the weather of the place where the vehicle is traveling via the Internet. Determination result data is acquired from the road surface condition determination unit 70 for determining the Details will be described later.

  Each configuration of the continuously variable transmission 4 will be described. The variator 20 and the auxiliary transmission 30 provided in series with the variator 20 are provided.

  The variator 20 is a belt-type continuously variable transmission that includes a primary pulley 21, a secondary pulley 22, and a V-belt 23 that is wound around the pulleys 21 and 22. Each of the pulleys 21 and 22 includes a fixed conical plate, a movable conical plate that is arranged with a sheave surface facing the fixed conical plate, and forms a V-groove between the fixed conical plate, and the movable conical plate. The hydraulic cylinders 23a and 23b are provided on the back surface of the movable cylinder to displace the movable conical plate in the axial direction. When the hydraulic pressure supplied to the hydraulic cylinders 23a and 23b is adjusted, the width of the V groove changes, the contact radius between the V belt 23 and the pulleys 21 and 22 changes, and the gear ratio vRatio of the variator 20 is stepless. Change.

  The sub-transmission 30 is a transmission mechanism having two forward speeds and one reverse speed. The sub-transmission 30 is connected to a Ravigneaux type planetary gear mechanism 31 in which two planetary gear carriers are coupled, and a plurality of friction elements connected to a plurality of rotating elements constituting the Ravigneaux type planetary gear mechanism 31 and changing their linkage state. Fastening elements (Low brake 32, High clutch 33, Rev brake 34) are provided. When the hydraulic pressure supplied to each of the frictional engagement elements 32 to 34 is adjusted and the engagement / release state of each of the frictional engagement elements 32 to 34 is changed, the gear position of the sub-transmission 30 is changed. For example, if the Low brake 32 is engaged and the High clutch 33 and the Rev brake 34 are released, the shift stage of the sub-transmission 30 becomes the first speed. If the high clutch 33 is engaged and the low brake 32 and the rev brake 34 are released, the speed stage of the sub-transmission 30 becomes the second speed, which is smaller than the first speed. Further, when the Rev brake 34 is engaged and the Low brake 32 and the High clutch 33 are released, the shift stage of the sub-transmission 30 is reverse.

  FIG. 2 is a schematic diagram illustrating a detection area in front of the vehicle by the sensor according to the first embodiment. A sensor (Laser LIDAR) 60 detects a road surface for each of a plurality of regions having different positions in front of the traveling vehicle. For example, as the long-distance area, the areas indicated by 1, 2 and 3 in FIG. 2, as the medium-distance area, as indicated by 4, 5 and 6, and as the short-distance area, 7, 8 and 9 are used. The area indicated by can be set. Further, as the right side area of the vehicle, the areas indicated by 1, 4 and 7 in FIG. 2, the central area as indicated by 2, 5 and 8, and the left area as 3, 6 and 9 are indicated. The indicated area can be set. FIG. 3 shows a sensor (Laser LIDAR) 60 that receives the reflected light of the road surface of each region set in this way.

  A sensor (Laser LIDAR) 60 shown in FIG. 3 receives a pulse current from a drive circuit (not shown) under the control of a control circuit, and intermittently emits a pulse laser beam in accordance with the pulse current, and a prism. 62 and an angle adjusting actuator 63 for rotating the prism. The laser light generated by the laser diode 61 is reflected by the prism 62 and transmitted to the detection target in front of the vehicle, and the scattered light reflected from the road surface to be detected is received by a light receiving unit (not shown). As shown in FIG. 3A, the angle adjusting actuator 63 is driven to rotate the prism 62, and the angle of the reflecting surface thereof is changed, thereby forming the horizontal direction of the laser light generated by the laser diode 61. The angle θ can be changed. On the other hand, with respect to the lateral direction of the vehicle, as shown in FIG. 3B, the sensor (Laser LIDAR) 60 can be rotated by 180 ° scanning.

FIG. 4 is a flowchart illustrating the content of the road surface state determination process in the road surface type determination unit according to the first embodiment.
In step S101, the road surface type determination unit 50 reads vehicle speed data from the vehicle speed sensor 43, and the process proceeds to step S102.

  In step S102, the road surface type determination unit 50 reads the vehicle speed-region table, and the process proceeds to step S103. Here, the vehicle speed-area table is a table that defines the correspondence between the vehicle speed and the area of road surface detection data used for road surface type determination, as shown in FIG. When the vehicle speed increases, even if the road surface condition near the traveling vehicle is determined, the road surface detection data obtained by the sensor 60 is received by the road surface condition determination unit 70 and subjected to image processing. Since it takes time until the determination, there is a risk of passing through that point at the time of determination. In addition, the reflected light received by the laser rider also decreases the road surface determination accuracy because the width of the measurement point increases as the road surface becomes farther. Therefore, the number and positions of road surface areas sufficient to obtain sufficient determination time and determination accuracy according to the vehicle speed are set in advance, and the vehicle speed-area table shown in FIG. 5 is prepared and received by the sensor (Laser LIDAR) 60. Of these data, only the data defined in the vehicle speed-area table is used to perform the calculation process for determining the road surface type. As shown in FIG. 5, the area of road surface detection data used during traveling at a high speed, for example, 80 km / hour, is the area indicated by 1, 2 and 3 in FIG. 2 (about 80 m ahead of the vehicle). For example, the area of road surface detection data used during traveling at 60 km / hour is the area indicated by 4, 5, 6 and 8 (approximately 30 m to 10 m ahead of the vehicle), and during traveling at a low speed, for example 40 km / hour. The area of road surface detection data to be used is an area indicated by 4, 5, 6, 7, 8, and 9 (about 30 m to 10 m in front of the vehicle).

  In step S103, the road surface type determination unit 50 compares the vehicle speed data read in step S101 with the vehicle speed-region table read in step S102, and road surface detection data to be used for the arithmetic processing corresponding to the current vehicle speed. Is determined, and the process ends.

  A method for determining a road surface state using one or a plurality of road surface detection data acquired or selected in this manner will be described below.

FIG. 6 is a flowchart illustrating the contents of the process of the road surface type determination unit according to the first embodiment.
In step S1, the road surface type determination unit 50 determines that the road surface is wet based on the rain information detected by the vibration sensor while the wiper is operating or the location where the vehicle is traveling via the Internet is wet. The determination result data is read, and the process proceeds to step 2.

  In step S2, if the road surface type determination unit 50 determines from the determination result data of the road surface state determination unit 70 that the road surface is wet, the process proceeds to step S9. If it is determined that the road surface is not wet, the process proceeds to step S3.

  In step S3, the road surface type determination unit 50 reads the road surface detection data of the area determined in step 103 from the sensor (Laser LIDAR) 60, and the process proceeds to step S4.

  In step S4, the road surface type determination unit 50 converts the read road surface detection data into a format comparable to the stored road surface learning data, and the process proceeds to step S5.

  In step S5, the road surface type determination unit 50 reads road surface learning data, and the process proceeds to step S6.

  Here, the road surface learning data includes four types of dry road surface learning data (asphalt road surface, concrete road surface, block road surface, gravel road surface).

In step S6, the road surface type determination unit 50 compares the read road surface detection data with the four types of road surface learning data and determines whether or not they match.
If they do not match, control according to the road surface type is prohibited, and the routine proceeds to step 9.
Or you may perform control according to the asphalt road surface with the largest safety factor.
If it matches any of the four types of road surface types, the process proceeds to step S7.
Note that a specific matching determination is made by determining that the road surface detection data and the road surface learning data are similar with a probability of 80% or more.

  In step S7, the road surface type determination unit 50 outputs the determined road surface type to the transmission controller 12, and the process proceeds to step S8. Here, the process of the road surface type determination unit 50 ends.

  In step S8, the transmission controller 12 changes to a hydraulic characteristic or a gear ratio characteristic according to the road surface type, and the process ends.

  In step S9, the wet road surface information is output to the transmission controller 12, and the process proceeds to step S10. Here, the process of the road surface type determination unit 50 ends.

In step S10, the transmission controller 12 changes the hydraulic characteristic or the gear ratio characteristic according to the wet road surface, and the process ends.
In the case of the present embodiment, the characteristics according to the asphalt road surface having the largest safety factor are used.

FIG. 7 is a schematic hydraulic characteristic diagram of the continuously variable transmission according to the road surface type according to the first embodiment.
The horizontal axis indicates the accelerator opening, and the vertical axis indicates the continuously variable transmission hydraulic pressure, for example, the line pressure.
The asphalt road surface with the highest wheel grip force has the highest hydraulic pressure, and then the concrete road surface, block road surface, and gravel road surface with the lowest grip force are set to the lowest oil pressure.
When the vehicle travels on a high μ road, there is a risk of belt slip due to the large torque received from the drive wheels 7, so it is necessary to supply high hydraulic pressure to the continuously variable transmission 4. On the other hand, on a low μ road, there is no large torque input from the drive wheels 7, so the hydraulic pressure can be lowered. For the purpose of preventing the belt slip while improving the fuel efficiency by performing the hydraulic control based on such a road surface type, the transmission controller 12 is configured according to the road surface type from the road surface type determination unit 50. The hydraulic characteristics are switched.

FIG. 8 is a time chart illustrating changes in hydraulic pressure of the continuously variable transmission during vehicle control of the vehicle control device according to the first embodiment.
The operation of the first embodiment will be described with reference to FIG.

The horizontal axis represents time, and the vertical axis represents the road surface type and the bottom represents the hydraulic pressure of the continuously variable transmission.
As described above, the road surface determination / determination unit (ADAS) 50 includes an appropriate road surface area corresponding to the vehicle speed in the reflected light data received by the sensor (Laser LIDAR) 60, for example, about 30 m to 10 m ahead when driving at medium speed. The road surface type is determined using the road surface detection data of the road surface (regions indicated by 4, 5, 6 and 8 in FIG. 2).
Therefore, at time t1, the road surface determination / determination unit (ADAS) 50 determines that the road ahead of the vehicle is about 30 m ahead of the currently running asphalt road surface, and starts traveling on the concrete road surface at time t2. Then, at time t2, a decrease in hydraulic pressure is gradually started toward the target hydraulic pressure based on the hydraulic characteristics of the concrete road surface provided in advance.
At time t3, the target hydraulic pressure is reached and maintained. Time T is the time to reach the concrete road surface after determination. Since this changes in accordance with the vehicle speed, the hydraulic control is started when the calculated time T has elapsed.

Next, the function and effect will be described.
The vehicle control device and the vehicle control method according to the first embodiment have the following effects.
(1) The road surface type determination unit 50 determines the road surface type based on the road surface detection data of one or more areas among the road surface detection data for each of the plurality of areas in front of the vehicle detected by the sensor 60. Specifically, the number and position of the region used for the vehicle are made variable depending on the vehicle speed.
Therefore, by adjusting the calculation processing time for performing road surface determination according to the vehicle speed, the processing load of the control unit can be reduced, and appropriate vehicle control can be performed at an appropriate timing.
(2) Also, when the vehicle speed is high, the number of areas is reduced compared to the low vehicle speed, and only a distant area is used for the determination, so that the calculation processing time in the road surface type determination unit is shortened and the vehicle is traveling as fast as possible. The oil pressure can be reduced up to. On the other hand, the road surface type determination accuracy can be improved by increasing the number of areas at low vehicle speeds and detecting nearby areas.

[Example 2]
FIG. 9 is a schematic gear ratio characteristic diagram of the continuously variable transmission at a predetermined throttle opening degree according to the road surface type according to the second embodiment.
The “speed ratio” is a value obtained by dividing the primary rotational speed Npri of the continuously variable transmission 4 by the output rotational speed (equivalent to the vehicle speed) of the continuously variable transmission 4.
The horizontal axis represents the vehicle speed, the vertical axis represents the primary rotational speed Npri, and shows the approximate gear ratio characteristic at a predetermined accelerator opening APO.
When comparing at the same vehicle speed and the same accelerator opening APO, the asphalt road surface with the highest wheel grip force has the highest speed ratio, and the next speed change is on the concrete road surface, block road surface, and gravel road surface with the lowest grip force. The ratio is set small.
The transmission controller 12 switches the gear ratio characteristics according to the road surface type from the road surface type determination unit 50.
In the case of a wet road surface, the characteristics of gravel road surface are used.

FIG. 10 is a time chart illustrating changes in the gear ratio of the continuously variable transmission during vehicle control of the vehicle control device according to the second embodiment.
The operation of the second embodiment will be described with reference to FIG.

The horizontal axis represents time, and the vertical axis represents the road surface type on the top and the gear ratio of the continuously variable transmission on the bottom.
As described above, the road surface discriminating / determining unit (ADAS) 50 has a suitable vehicle front distance according to the vehicle speed in the reflected light data received by the sensor (Laser LIDAR) 60. The road surface type is determined using the road surface detection data of (the areas indicated by 1, 2 and 3 in FIG. 2).
Therefore, at time t1, the road surface determination / determination unit (ADAS) 50 determines that about 80 m ahead of the vehicle is a gravel road surface, and gradually shifts the speed toward the target gear ratio according to the characteristics of the gravel road surface in advance at time t2. Start.
When the target speed ratio is reached at time t3, the target speed ratio is maintained, and at the time t4, traveling on the gravel road surface is started. Time T is the time to reach the gravel road surface after the determination. Since this changes according to the vehicle speed, the control is completed within the calculated time T.

Next, the function and effect will be described.
The vehicle control device and the vehicle control method according to the second embodiment have the following effects.
(1) The road surface type determination unit 50 determines the road surface type based on the road surface detection data of one or more areas among the road surface detection data for each of the plurality of areas in front of the vehicle detected by the sensor 60. Specifically, the number and position of the region used for the vehicle are made variable depending on the vehicle speed.
Therefore, since it is possible to adjust the calculation processing time for performing road surface determination according to the vehicle speed, the gear ratio of the continuously variable transmission 4 can be set appropriately, and fuel saving is achieved while ensuring safety. can do.
(2) When the gear ratio is upshifted (shifting from the larger side to the smaller side), the gear ratio of the continuously variable transmission 4 is set in advance to the target gear ratio in consideration of the detection distance and the vehicle speed. The target gear ratio is set when traveling on the detected road surface.
Therefore, it is possible to prevent wasteful driving wheel slip on a low μ road surface such as a gravel road surface.

[Example 3]
FIG. 11 is a flowchart illustrating the contents of the process of the road surface type determination unit according to the third embodiment.
Steps up to step S6 are the same as those in the flowcharts of the first and second embodiments shown in FIG. 6 and are therefore denoted by the same reference numerals, and therefore will not be described.

  In step S17, the road surface type determination unit 50 outputs the determined road surface type to the engine controller 1a, and the process proceeds to step S18. Here, the process of the road surface type determination unit 50 ends.

  In step S18, the engine controller 1a changes to an engine output characteristic corresponding to the road surface type, and the process ends.

  In step S19, the road surface type determination unit 50 outputs wet road surface information to the engine controller 1a, and the process proceeds to step S20. Here, the process of the road surface type determination unit 50 ends.

In step S20, the engine controller 1a changes to an engine output characteristic corresponding to a wet road surface, and the process ends.
In the case of the present embodiment, the characteristic is according to the gravel road surface having the highest safety factor.

FIG. 12 is a schematic output characteristic diagram of the engine according to the road surface type according to the third embodiment.
The horizontal axis indicates the throttle opening, and the vertical axis indicates the engine output.
The asphalt road surface with the highest wheel grip force has the highest engine output for the accelerator opening APO, then the concrete road surface, the block road surface, and the gravel road surface with the lowest grip force have the lowest engine output for the accelerator opening APO. It is set.
The engine controller 1 a switches the engine output characteristics according to the road surface type from the road surface type determination unit 50.
In the case of a wet road surface, the characteristics of gravel road surface are used.

FIG. 13 is a time chart illustrating changes in engine output during vehicle control of the vehicle control device according to the third embodiment.
The operation of the third embodiment will be described with reference to FIG.
The horizontal axis indicates time, and the vertical axis indicates the road surface type and the lower side indicates the engine output.
As described above, the road surface determination / determination unit (ADAS) 50 includes an appropriate distance ahead of the vehicle according to the vehicle speed in the reflected light data received by the sensor (Laser LIDAR) 60, for example, about 30 m to 10 m ahead when traveling at low speed. The road surface type is determined using the road surface detection data of the road surface (regions indicated by 4, 5, 6, 7, 8, and 9 in FIG. 2).
Therefore, at time t1, the road surface determination / determination unit (ADAS) 50 determines that about 30 m ahead of the vehicle is a gravel road surface, and gradually toward the target engine output according to the characteristics of the gravel road surface in advance at time t2. Begins to decline.
When the target engine output is reached at time t3, the target engine output is maintained and traveling on the gravel road surface is started at time t4. Time T is the time to reach the gravel road surface after the determination. Since this changes according to the vehicle speed, the control is completed within the calculated time T.

Next, the function and effect will be described.
The vehicle control device and the vehicle control method according to the third embodiment have the following effects.
(1) The road surface type determination unit 50 determines the road surface type based on the road surface detection data of one or more areas among the road surface detection data for each of the plurality of areas in front of the vehicle detected by the sensor 60. Specifically, the number and position of the region used for the vehicle are made variable depending on the vehicle speed.
Therefore, since the calculation processing time for performing road surface determination can be adjusted according to the vehicle speed, the output of the engine 1 can be set appropriately, and fuel consumption can be realized while ensuring safety. .
(2) Further, the road surface type determination accuracy can be improved by increasing the number of areas at low vehicle speeds and detecting nearby areas.

[Example 4]
FIG. 14 is a flowchart illustrating the contents of the process of the road surface type determination unit according to the fourth embodiment. Steps up to step S6 are the same as those in the flowcharts of the first and second embodiments shown in FIG. 6 and are therefore denoted by the same reference numerals, and therefore will not be described.

  In step S27, the road surface type determination unit 50 outputs the determined road surface type to the brake controller 100, and the process proceeds to step S28. Here, the process of the road surface type determination unit 50 ends.

  In step S28, the brake controller 100 changes to the brake pressure characteristic according to the road surface type, and the process ends.

  In step S29, the road surface type determination unit 50 outputs wet road surface information to the brake controller 100, and the process proceeds to step S30. Here, the process of the road surface type determination unit 50 ends.

In step S30, the brake controller 100 changes to a brake pressure characteristic corresponding to a wet road surface, and the process ends.
In the case of the present Example, it is set as the characteristic according to the gravel road surface with the largest safety factor.

FIG. 15 is a schematic brake pressure characteristic diagram according to the road surface type according to the fourth embodiment.
The horizontal axis represents the brake pedal force, and the vertical axis represents the brake pressure.
The asphalt road surface with the highest wheel grip force has the highest brake pressure with respect to the brake pedal force, then the concrete road surface, the block road surface, and the gravel road surface with the lowest grip force have the lowest brake pressure with respect to the brake pedal force. .
The brake controller 100 switches the brake pressure characteristics according to the road surface type from the road surface type determination unit 50.
In the case of a wet road surface, the characteristics of gravel road surface are used.

FIG. 16 is a time chart illustrating changes in brake pressure during vehicle control of the vehicle control device according to the fourth embodiment.
The operation of the fourth embodiment will be described with reference to FIG.
The horizontal axis represents time, and the vertical axis represents the road surface type and the bottom represents the brake pressure.
As described above, the road surface determination / determination unit (ADAS) 50 includes an appropriate distance ahead of the vehicle according to the vehicle speed in the reflected light data received by the sensor (Laser LIDAR) 60, for example, about 30 m to 10 m ahead when traveling at low speed. The road surface type is determined using the road surface detection data of the road surface (regions indicated by 4, 5, 6, 7, 8, and 9 in FIG. 2).
Therefore, at time t1, the road surface determination / determination unit (ADAS) 50 determines that about 30 m ahead of the vehicle is a gravel road surface, and gradually increases the brake pressure toward the target brake pressure according to the characteristics of the gravel road surface in advance at time t2. Begins to decline.
When the target brake pressure is reached at time t3, the target brake pressure is maintained and traveling on the gravel road surface is started at time t4. Time T is the time to reach the gravel road surface after the determination. Since this changes according to the vehicle speed, the control is completed within the calculated time T.

Next, the function and effect will be described.
The vehicle control device and the vehicle control method according to the fourth embodiment have the following effects.
(1) The road surface type determination unit 50 determines the road surface type based on the road surface detection data of one or more areas among the road surface detection data for each of the plurality of areas in front of the vehicle detected by the sensor 60. Specifically, the number and position of the region used for the vehicle are made variable depending on the vehicle speed.
Therefore, since the calculation processing time for performing the road surface determination can be adjusted according to the vehicle speed, the brake pressure for the brake pedal force can be appropriately set, and fuel consumption can be realized while ensuring safety. it can.
(2) In consideration of the detection distance and the vehicle speed, the brake pressure with respect to the brake depression force is set as the target brake pressure in advance, and is reliably set as the target brake pressure when traveling on the detected road surface.
Therefore, it is possible to prevent wasteful driving wheel slip on a low μ road surface such as a gravel road surface.

As mentioned above, although the form for implementing this invention was demonstrated based on the Example, the specific structure of this invention is not limited to the structure shown in the Example, The range which does not deviate from the summary of invention. Such design changes are included in the present invention.
In the above-described embodiment, learning data of four types of road surface conditions is included, but not limited to this, a road surface mixed with sand may be added. The vehicle speed sensor 43 in the above embodiment is a sensor that measures the number of rotations of the output shaft of the transmission. However, the vehicle speed sensor 43 may be a wheel speed sensor that is arranged on each wheel and generates a pulse signal at a cycle according to the wheel speed. Good.
The road surface type determination unit (ADAS) 50 calculates the reflectance of the road surface using the reflected light detected by the sensor (Laser LIDAR) 60, but the sensor (Laser LIDAR) 60 has its own control unit. The reflectance of the road surface may be calculated. Any form is included in the scope of the present invention.
Further, in the above embodiment, the sensor 60 receives the reflected light of all areas, and the road surface type determination unit 50 selects only the road surface detection data of the determined area, and performs the road surface type determination process. The road surface type determination unit 50 may determine the use area of the road surface detection data, the sensor 60 may receive only the road surface detection data of the determined area, and the road surface type determination unit 50 may perform the road surface type determination process. .

1a Engine controller (vehicle control unit)
12 Transmission controller (vehicle control unit)
50 Road surface type determination unit (ADAS)
60 sensors (Laser LIDAR)
70 Road surface condition judgment part

Claims (4)

A sensor for irradiating light around the vehicle and detecting reflected light;
A road surface type determination unit that calculates road surface reflectance based on road surface detection data detected by the sensor and determines a road surface type;
A vehicle control unit that controls the vehicle based on the determination result of the road surface type determination unit;
A vehicle speed sensor for detecting the traveling speed of the vehicle;
In a vehicle control device comprising:
The road surface type determination unit determines a road surface type based on road surface detection data of the one or a plurality of areas among road surface detection data for a plurality of areas in front of the vehicle detected by the sensor, and is used for the determination. Making the area variable according to vehicle speed,
A vehicle control device. The vehicle control device according to claim 1,
The road surface type determination unit reduces the number of areas used for determination of the road surface type as the vehicle speed increases;
A vehicle control device. In the vehicle control device according to claim 1 or 2,
The road surface type determination unit sets the position of the region used for the determination of the road surface type as a region farther from the vehicle as the vehicle speed increases.
A vehicle control device. A sensor for irradiating light around the vehicle and detecting reflected light;
A road surface type determination unit that calculates road surface reflectance based on road surface detection data detected by the sensor and determines a road surface type;
A vehicle control unit that controls the vehicle based on the determination result of the road surface type determination unit;
A vehicle speed sensor for detecting the traveling speed of the vehicle,
A vehicle control method for controlling a vehicle based on a road surface type,
Obtaining a vehicle speed from the vehicle speed sensor;
Determining an area for determining a road surface type with respect to the vehicle speed;
Determining a road surface type based on road surface detection data of the determined area.

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