CN110370940B - Steep slope slow descent constant speed cruise system and method - Google Patents

Abstract

The invention discloses a steep-slope slow-descending constant-speed cruise system and a method, which relate to the technical field of new energy automobile control, wherein the system comprises a touch screen, a constant-speed cruise key, a slope sensor and a motor controller which are respectively connected with a vehicle control unit, and the motor controller is connected with a motor; the touch screen is used for sending a first instruction to the vehicle control unit; the constant-speed cruise key is used for sending a second instruction to the vehicle control unit; the gradient sensor is used for sending a current gradient value to the vehicle control unit; and the vehicle control unit is used for judging whether a second instruction is received after receiving the first instruction, judging whether the second instruction is received again after receiving the second instruction, and regulating the output torque of the motor through the motor controller to maintain the vehicle speed at the first target speed if the second instruction is received again and the current gradient value is greater than the first threshold value. The invention can continuously regulate the speed of the steep descent and improve the driving comfort and safety.

Description

Steep slope slow descent constant speed cruise system and method

technical field

The invention relates to the technical field of new energy vehicle control, in particular to a steady-speed cruise system and a method for slow descent on steep slopes.

Background technique

When going downhill, because the downhill is affected by the acceleration of gravity, the speed of the vehicle will gradually increase even if the accelerator is not stepped on. Especially for inexperienced drivers, they will slam on the brakes when the vehicle speed is high, causing the tires to lock and lose their grip. In addition to being suitable for relatively steep slopes, it is also suitable for gravel, mud or ice and snow slope roads to ensure the safe descent of the vehicle.

The basic principle of the steep slope descent function of traditional fuel vehicles is to combine the engine brakes and the ABS system to maintain a low speed when going down a steep slope, and cooperate with the gearbox to reduce to 1st gear to achieve a low speed downhill state. For traditional fuel vehicles, this function is complicated to implement, and the calibration cost is high.

The patent with the application number of 201410670024.8 is a steep slope descent system for pure electric vehicles and its control method, which provides a steep slope descent system for electric vehicles, which can determine the upper limit vehicle speed through a table look-up method according to the slope, but the patent needs to increase The control key for steep hill descent, and the downhill speed cannot be controlled continuously. The patent with the application number of 201611105397.6. is a method and device for gentle descent on a steep slope applied to an electric vehicle. By judging the acceleration of the vehicle and the opening of the accelerator pedal, the output reverse torque is determined, and the threshold calibration is difficult to set, which is easy to confuse the downhill working condition. and acceleration conditions, in addition, the downhill speed is not continuously controllable.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a steady-speed cruise system for steep slope descent, which starts the steep slope descent through a soft switch, thereby saving the steep slope descent hardware switch, and at the same time enabling continuous adjustment of the steep slope descent speed.

Embodiments of the present invention are implemented as follows:

Specifically, a steady-speed cruise system with gentle descent on steep slopes includes a vehicle controller, a touch screen, a cruise control button, a gradient sensor, a motor controller, and a motor, wherein the touch screen, the cruise control button, and the motor controller are respectively associated with the the vehicle controller is connected, and the motor controller is connected with the motor;

The touch screen is used to send a first instruction to the vehicle controller;

The cruise control button is used to send a second instruction to the vehicle controller;

The gradient sensor is used to send the current gradient value to the vehicle controller;

The vehicle controller is used to determine whether the second command is received after receiving the first command, and after receiving the second command, determine whether the second command is received again, if the second command is received again Second instruction, when the vehicle controller judges that the current gradient value is greater than the first threshold value, it enters the steep gradient descent mode and sends a third instruction to the motor controller;

The motor controller is configured to adjust the output torque of the motor after receiving the third command, so as to maintain the vehicle speed at the first target speed.

Further, the first target speed is the vehicle speed when the vehicle controller receives the second instruction again.

Further, the system further includes a cruise control cancel button, the cruise control cancel button is used to send a fourth instruction to the vehicle controller, and the vehicle controller exits the steep slope after receiving the fourth instruction. model;

The touch screen is also used to send a fifth instruction to the vehicle controller, and the vehicle controller exits the steep slope descent mode after receiving the fifth instruction.

Further, the system further includes a brake pedal and an accelerator pedal, and the brake pedal and the accelerator pedal are respectively connected with the vehicle controller;

The brake pedal is used to send a switch signal of the brake pedal to the vehicle controller;

The accelerator pedal is used to send an accelerator pedal opening signal to the vehicle controller;

The first target speed is adjusted by controlling the brake pedal or the accelerator pedal.

Further, when the vehicle controller receives the switch signal of the brake pedal and judges that the valid time of the brake pedal switch signal is less than the second threshold, the vehicle controller sends a sixth instruction to the motor controller, so that The motor controller controls the output torque of the motor so that the vehicle speed returns to the first target speed and maintains the first target speed.

Specifically, a steady-speed cruise method for gentle descent on a steep slope includes:

S1. Determine whether the first command is received by the vehicle controller, if so, execute S2, otherwise, execute S1;

S2. Determine whether the second instruction is received by the vehicle controller, if so, execute S3, otherwise, execute S2;

S3. Determine whether the second instruction is received again by the vehicle controller, if so, execute S4, otherwise, execute S3;

S4. The vehicle controller obtains the current gradient value through the gradient sensor, and judges whether the current gradient value is greater than the first threshold value, if so, execute S5, otherwise, execute S4;

S5. Enter the steep slope descent mode, send the third command to the motor controller through the vehicle controller, and the motor controller adjusts the output torque of the motor after receiving the third command, so as to maintain the vehicle speed at the first target speed.

Further, the first target speed is the vehicle speed when the vehicle controller receives the second instruction again.

Further, after step S5, it also includes:

The vehicle controller determines whether the fourth command sent by the cruise control cancel button or the fifth command sent by the touch screen is received.

Further, step S3 also includes adjusting the first target speed through a brake pedal or an accelerator pedal, and the specific process is as follows:

Decrease the first target speed through the brake pedal. The specific process is as follows: decelerate through the brake pedal. When the first target speed drops to the target speed, press the cruise control button, and use the cruise control button. send the second instruction to the vehicle controller by pressing the button;

The first target speed is increased by the accelerator pedal. The specific process is: accelerating by the accelerator pedal, when the first target speed reaches the target speed, press the cruise control button, and press the cruise control button to the The vehicle controller sends the second instruction.

Further, after step S5, it also includes:

Receive the switch signal of the brake pedal through the vehicle controller, and determine whether the effective time of the brake pedal switch signal is less than the second threshold, if it is less than the second threshold, send the first threshold to the motor controller through the vehicle controller Sixth command, the motor controller controls the output torque of the motor to restore the vehicle speed to the first target speed and maintain the first target speed.

The beneficial effects of the present invention are:

The hardware switch for starting steep hill descent is omitted, and the soft switch and cruise control button on the touch screen are used to start or exit steep hill descent, which saves hardware costs; the speed of steep hill descent is adjusted through the brake pedal and accelerator pedal. Speed, and can lock the steep slope descent speed through the cruise control button, so as to realize the continuous speed regulation of the steep slope descent speed.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore do not It should be regarded as a limitation of the scope, and for those of ordinary skill in the art, other related drawings can also be obtained according to these drawings without any creative effort.

1 is a schematic structural diagram of a steep slope gentle descent constant speed cruise system provided by a preferred embodiment of the present invention;

FIG. 2 is a flow chart of a method for cruising at a steady speed with gentle descent on a steep slope according to a preferred embodiment of the present invention.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments These are some embodiments of the present invention, but not all embodiments. The components of the embodiments of the invention generally described and illustrated in the drawings herein may be arranged and designed in a variety of different configurations.

Thus, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

It should be noted that like numerals and letters refer to like items in the following figures, so once an item is defined in one figure, it does not require further definition and explanation in subsequent figures.

The terms "first", "second", "third", etc. are only used to differentiate the description and should not be construed as indicating or implying relative importance.

As shown in FIG. 1, it is a schematic structural diagram of a steep slope slow descent cruise control system provided by a preferred embodiment of the present invention. The system is applied to electric vehicles, including a vehicle controller, a touch screen, cruise control buttons, cruise control Cancel button, gradient sensor, brake pedal, accelerator pedal, instrument, motor controller and motor, among which the cruise control button and cruise control cancel button are all set on the steering wheel, so that users can easily pass the cruise control button during driving. The speed cruise button sends a second instruction for determining the first target speed to the vehicle controller, or a fourth instruction for exiting steep slope descent is sent to the vehicle controller through the cruise control cancel button.

The touch screen, cruise control button, cruise control cancel button, gradient sensor, brake pedal, accelerator pedal, instrument and motor controller are respectively electrically connected to the vehicle controller, the motor controller is connected to the motor, and the motor is used to drive the vehicle . Among them, the gradient sensor, the brake pedal and the accelerator pedal collect the gradient data of the vehicle, the brake pedal switch signal and the accelerator pedal opening signal in real time and send them to the vehicle controller. The devices can be electrically connected through one or more communication buses or signal lines to realize data transmission or interaction.

The user can realize the deceleration or acceleration of the vehicle speed by controlling the brake pedal or the accelerator pedal, so as to adjust the first target speed in cooperation with the cruise control button.

The touch screen provides an interactive interface (such as a user operation interface) between the vehicle controller and the user or is used to display image data for the user's reference. In this embodiment, the touch screen may be a liquid crystal touch screen, and may be a capacitive touch screen or a resistive touch screen that supports single-point and multi-point touch operations. Supporting single-point and multi-touch operation means that the touch screen can sense the touch operation generated from one or more positions on the touch screen at the same time, and pass the sensed touch operation to the vehicle controller for calculation and calculation. deal with. In this embodiment, the touch screen is provided with a virtual button for starting/exiting the steep slope descent, and the user sends the first instruction to start the steep slope descent or the fifth instruction to exit the steep slope descent to the vehicle controller by touching the virtual button. .

The vehicle controller may be a general-purpose processor, including a central processing unit (CPU for short), a network processor (NP for short), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit ( ASIC), off-the-shelf programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. Various methods, steps, and logical block diagrams disclosed in the embodiments of the present invention can be implemented or executed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The vehicle controller is used to determine whether to receive the second instruction after receiving the first instruction, and to determine whether to receive the second instruction again after receiving the second instruction. If the second instruction is received again, the vehicle controls When the controller determines that the current gradient value is greater than the first threshold value, it enters the steep gradient descent mode and sends a third instruction to the motor controller.

The motor controller is configured to adjust the output torque of the motor after receiving the third command to maintain the vehicle speed at the first target speed, wherein the first target speed is the vehicle speed when the vehicle controller receives the second command again.

After the vehicle controller receives the fourth command or the fifth command, it exits the steep descent mode.

After entering the steep slope, if the vehicle controller receives the switch signal of the brake pedal during the steep slope descent, the vehicle controller records the effective time of the brake pedal switch signal through the timer, and judges the brake pedal. The valid time of the switch signal is less than the second threshold. If it is less than the second threshold, the vehicle controller sends a sixth instruction to the motor controller, and the motor controller controls the output torque of the motor, so that the vehicle speed returns to the first target speed and maintains the first target. The speed ensures a constant speed during the steep descent, wherein the effective time is the time from when the user depresses the brake pedal to when the brake pedal is completely released.

As shown in Figure 2, a method for cruise control with slow descent on steep slopes, applied to a cruise control system with slow descent on steep slopes, can also be implemented independently, including:

S1. The vehicle controller judges whether the first command is received, and if so, it is judged that the user has sent the first command to the vehicle controller through the virtual button on the touch screen, starts the steep slope descent mode, and enters the steep slope descent wait. state, execute S2, otherwise, execute S1.

S2. Determine whether the second command sent by the cruise control button is received through the vehicle controller. If S3 is executed, the cruise control icon on the instrument will light up and flash, otherwise, execute S2.

S3. Determine whether the second instruction is received again by the vehicle controller, if so, execute S4, otherwise, execute S3;

The user can adjust the first target speed through the brake pedal or the accelerator pedal, including the following two situations:

Decrease the first target speed through the brake pedal. The specific process is as follows: when the speed needs to be decelerated, the user depresses the brake pedal to decelerate. When the first target speed drops to the target speed expected by the user, the user presses the cruise control button. Press the button, and send the second command to the vehicle controller through the cruise control button;

The first target speed is increased by the accelerator pedal. The specific process is that when acceleration is required, the user accelerates by depressing the accelerator pedal. When the first target speed reaches the target speed expected by the user, the user presses the cruise control button, and the The cruise button sends a second command to the vehicle controller.

S4. The vehicle controller obtains the current gradient value through the gradient sensor, and judges whether the current gradient value is greater than the first threshold, wherein the first threshold is set to 8%, and if so, the vehicle controller determines that the vehicle is in compliance with the steep slope descent The condition of the state, execute S5, otherwise, execute S4.

S5. Enter the steep slope descent mode, the vehicle controller sends a third command to the motor controller, and the motor controller adjusts the output torque of the motor after receiving the third command to maintain the vehicle speed at the first target speed. At this time, the meter The cruise control icon on the top is always on, indicating that the vehicle has entered the steep descent mode. The first target speed is the speed of the entire vehicle when the vehicle controller receives the second command again.

If the user needs to change the cruise control speed for steep slope descent, the vehicle speed can be adjusted again through the brake pedal or accelerator pedal, and the cruise control speed can be adjusted by cooperating with the cruise control button.

S6. During the steep slope descent, if the user steps on the brake pedal, the vehicle controller receives the brake pedal switch signal, records the effective time of the brake pedal, and judges whether the effective time of the brake pedal switch signal is less than The second threshold, the second threshold can be set to 5S. If it is smaller than the second threshold, the vehicle controller sends a sixth instruction to the motor controller, and the motor controller controls the output torque of the motor to restore the vehicle speed to the first target speed and maintain the first target speed. A target speed, maintain the cruise at a steady speed with a gentle descent on steep slopes; if the effective time of the switch signal of the brake pedal is greater than the second threshold, the vehicle controller determines that the user needs to stop or there is an emergency situation that requires braking. At this time, the vehicle control to exit the hill-descent mode.

During the steep slope descent, if the user steps on the accelerator pedal, the vehicle controller receives the accelerator pedal opening signal, and controls the output torque of the motor through the motor controller to achieve vehicle acceleration, and when the user releases the accelerator pedal After that, the output torque of the motor is controlled by the motor controller to restore the vehicle speed to the first target speed and maintain the first target speed, and maintain constant speed cruise in the steep descent mode.

During the steep slope descent, the vehicle controller determines whether it receives the fourth command sent by the cruise control cancel button or the fifth command sent by the touch screen. If the fourth or fifth command is received, the vehicle controller exits the steep slope descent. drop mode.

For example, when the vehicle is driving on a mountain road, the user activates the steep hill descent mode by touching the virtual button on the touch screen, and presses the cruise control button on the steering wheel to activate the steep hill descent mode, and the vehicle enters the steep hill descent preparation state. At this time, the cruise icon on the instrument is lit and flashing. When the vehicle speed is 20km/h and the gradient obtained by the gradient sensor is 10%, the vehicle controller determines that the current state of the vehicle meets the state of entering the steep slope and gentle descent. At this time, the user Press the cruise control button to send a second command to the vehicle controller to lock the current vehicle speed as the first target speed for cruise control. Speed down the ramp for cruise control. If the user needs to accelerate, the user will increase the vehicle speed to 21.5km/h through the accelerator pedal, and press the cruise control button again, the vehicle controller will lock the cruise speed at 21.5km/h through the motor controller. After the vehicle enters a flat road, the user exits the steep descent mode by pressing the cruise control cancel button.

If the vehicle descends slowly on a steep mountain road at a speed of 20km/h, the road ahead is empty and there are no cars, and the user depresses the accelerator pedal to accelerate. When the vehicle speed reaches 33km/h, there is a car at a distance ahead, and the user releases the accelerator pedal. , since the user did not press the cruise control button, the cruise speed of the vehicle is still 20km/h, then the vehicle gradually decelerates and stabilizes to a speed of 20km/h again for steep descent cruise; On a steep curve, the user depresses the brake pedal, turns the corner after 3S, the vehicle speed is reduced to 6km/h, the user releases the brake pedal, because the effective time of the switch signal of the brake pedal is less than the set second threshold 5S , the vehicle gradually accelerates and stabilizes again to 20km/h steep slope cruising.

To sum up, the present invention activates the steep slope descent mode by cooperating with the virtual buttons arranged on the touch screen and the cruise control buttons arranged on the steering wheel, so as to avoid misoperation by the user, and at the same time, the hardware switch for steep slope descent is omitted, and the hardware cost is saved. . Different steep descent states are displayed through the instrument, so that the user can intuitively know whether the current vehicle is in the steep descent mode, and the speed of the steep descent can be adjusted through the brake pedal and accelerator pedal, and can be locked by the cruise control button. Steep slope descent speed, so as to realize continuous speed regulation of steep slope descent speed. At the same time, if the user operates the brake pedal or accelerator pedal during the steep slope descent process, but does not lock the steep slope descent cruise speed through the cruise control button, the When the vehicle controller judges that the brake pedal or accelerator pedal is completely released, the motor controller can control the output torque of the motor to restore the locked steep slope descent speed, which can effectively keep the steep slope descent speed constant and improve driving comfort. sex and safety.

In the embodiments provided in this application, it should be understood that the disclosed systems and methods can also be implemented in other manners. The system embodiments described above are merely illustrative, and each block in the flowchart or block diagram may represent a module, program segment, or portion of code, which includes one or more Executable instructions for implementing specified logical functions. It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It is also noted that each block of the block diagrams and/or flowchart illustrations, and combinations of blocks in the block diagrams and/or flowchart illustrations, can be implemented in dedicated hardware-based systems that perform the specified functions or actions , or can be implemented in a combination of dedicated hardware and computer instructions.

If the method of this embodiment is implemented in the form of a software function module and sold or used as an independent product, it may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention can be embodied in the form of a software product in essence, or the part that contributes to the prior art or the part of the technical solution. The computer software product is stored in a storage medium, including Several instructions are used to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes: U disk, removable hard disk, Read-Only Memory (ROM, Read-Only Memory), Random Access Memory (RAM, Random Access Memory), magnetic disk or optical disk and other media that can store program codes .

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. A steep slope slow descent cruise control system is characterized in that, comprising vehicle controller, touch screen, cruise control button, gradient sensor, motor controller and motor, the touch screen, cruise control button and motor controller are respectively connected with the vehicle controller, and the motor controller is connected with the motor; The touch screen is used to send a first instruction to the vehicle controller; The cruise control button is used to send a second instruction to the vehicle controller; The gradient sensor is used to send the current gradient value to the vehicle controller; The vehicle controller is used to determine whether the second command is received after receiving the first command, and after receiving the second command, determine whether the second command is received again, if the second command is received again Second instruction, when the vehicle controller judges that the current gradient value is greater than the first threshold value, it enters the steep gradient descent mode and sends a third instruction to the motor controller; The motor controller is configured to adjust the output torque of the motor after receiving the third command, so as to maintain the vehicle speed at the first target speed. 2 . The cruise control system according to claim 1 , wherein the first target speed is the vehicle speed when the vehicle controller receives the second command again. 3 . 3 . The steep slope slow descent cruise control system according to claim 1 , wherein the system further comprises a cruise control cancel button, and the cruise control cancel button is used to notify the vehicle controller 3 . Send the fourth command, the vehicle controller will exit the steep slope descent mode after receiving the fourth command; The touch screen is also used to send a fifth instruction to the vehicle controller, and the vehicle controller exits the steep slope descent mode after receiving the fifth instruction. 4. A kind of steep slope slow descent cruise control system according to claim 1, is characterized in that, described system also comprises brake pedal and accelerator pedal, described brake pedal and accelerator pedal are respectively with described vehicle control device connection; The brake pedal is used to send a switch signal of the brake pedal to the vehicle controller; The accelerator pedal is used to send an accelerator pedal opening signal to the vehicle controller; The first target speed is adjusted by controlling the brake pedal or the accelerator pedal. 5 . The cruise control system according to claim 4 , wherein the vehicle controller receives the switch signal of the brake pedal and judges that the effective time of the switch signal of the brake pedal is less than the first 5. 5 . When there are two thresholds, the vehicle controller sends a sixth instruction to the motor controller, so that the motor controller controls the output torque of the motor, so that the vehicle speed returns to the first target speed and maintains the first target speed. 6 . A steady-speed cruise control method for slow descent on steep slopes, which is applied to a steady-speed cruise control system for steady descent on steep slopes according to any one of claims 1 to 5 , wherein the method comprises: S1. Determine whether the first instruction is received by the vehicle controller, if so, execute S2, otherwise, execute S1; S2. Determine whether the second instruction is received by the vehicle controller, if so, execute S3, otherwise, execute S2; S3. Determine whether the second instruction is received again by the vehicle controller, if so, execute S4, otherwise, execute S3; S4. the vehicle controller obtains the current gradient value through the gradient sensor, and judges whether the current gradient value is greater than the first threshold value, if so, execute S5, otherwise, execute S4; S5. Enter the steep slope descending mode, send the third command to the motor controller through the vehicle controller, and the motor controller adjusts the output torque of the motor after receiving the third command, so that the vehicle speed is maintained at first target speed. 7 . The method for cruising with a gentle descent on a steep slope according to claim 6 , wherein the first target speed is the vehicle speed when the vehicle controller receives the second command again. 8 . 8. a kind of steep slope gentle descent constant speed cruise method according to claim 6, is characterized in that, after step S5 also comprises: The vehicle controller determines whether the fourth command sent by the cruise control cancel button or the fifth command sent by the touch screen is received. If the fourth command or the fifth command is received, the vehicle controller controls to exit the steep slope. Slow down mode. 9. The method for cruising with a gentle descent on a steep slope according to claim 6, wherein step S3 further comprises: adjusting the first target speed through a brake pedal or an accelerator pedal, and the specific process is as follows: Decrease the first target speed through the brake pedal. The specific process is as follows: decelerate through the brake pedal. When the first target speed drops to the target speed, press the cruise control button, and cruise through cruise control. send the second instruction to the vehicle controller by pressing the button; The first target speed is increased by using the accelerator pedal. The specific process is: accelerating by using the accelerator pedal. When the first target speed reaches the target speed, press the cruise control button, and press the cruise control button to the target speed. The vehicle controller sends the second instruction. 10. The method for cruising at a slow descent on a steep slope according to claim 6, characterized in that, after step S5, the method further comprises: Receive the switch signal of the brake pedal through the vehicle controller, and determine whether the effective time of the brake pedal switch signal is less than the second threshold, if it is less than the vehicle controller, send a sixth instruction to the motor controller through the vehicle controller , the motor controller controls the output torque of the motor to restore the vehicle speed to the first target speed and maintain the first target speed.

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