Vehicle braking control method and system, medium and electronic equipment

Abstract

The invention provides a brake control method and system of a vehicle, a medium and electronic equipment, and relates to the field of automobile brake control, and the brake control method comprises the following steps: determining a kp parameter and a ki parameter of a first preset pi controller according to a damping coefficient of a vehicle shock absorber so as to reach preset brake response time; when the vehicle speed of the vehicle is lower than a first preset value and the target deceleration of the vehicle is lower than a second preset value, a first preset pi controller is used for determining the current deceleration of the vehicle based on the preset braking response time, and braking control is conducted on the vehicle; and when the vehicle speed of the vehicle is not lower than the first preset value or the target deceleration of the vehicle is not lower than the second preset value, the current deceleration of the vehicle is determined through a second preset pi controller, and braking control is conducted on the vehicle. The problem that in the prior art, when brake control is carried out, user experience is poor is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle braking control, and in particular to a vehicle braking control method, system, medium and electronic equipment. Background Art

[0002] In recent years, electronically controlled brake systems have been widely used as brake systems for vehicles. The electronically controlled brake systems control the braking force applied to each wheel so that an optimum braking force is applied to the vehicle in accordance with the running condition of the vehicle.

[0003] The current control of vehicle chassis braking is mainly based on a set of PI closed-loop control algorithms for braking response;

[0004] When using the above-mentioned PI closed-loop control algorithm for braking response, if the actual suspension of the vehicle is soft, the vehicle will have a more obvious front and rear pitch when braking, that is, the vehicle will have a more obvious "nodding feeling" when braking, which greatly affects the vehicle user experience. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a vehicle braking control method, system, medium and electronic equipment, which solve the problem of poor user experience when performing braking control in the prior art.

[0006] At least one embodiment of the present invention provides a vehicle braking control method, comprising:

[0007] Determining a kp parameter and a ki parameter of a first preset pi controller according to a damping coefficient of a vehicle shock absorber to achieve a preset braking response time;

[0008] When the vehicle speed is lower than a first preset value and the target deceleration of the vehicle is lower than a second preset value, using a first preset pi controller to determine the current deceleration of the vehicle based on the preset braking response time and perform braking control on the vehicle;

[0009] When the vehicle speed is not lower than the first preset value or the target deceleration of the vehicle is not lower than the second preset value, the second preset pi controller is used to determine the current deceleration of the vehicle and perform braking control on the vehicle.

[0010] The technical solution disclosed in the present invention has at least the following beneficial effects:

[0011] According to the damping coefficient of the vehicle shock absorber, when the suspension of the vehicle chassis is soft, the kp parameter and ki parameter of the first preset pi controller can be adjusted to change the response time of the first preset pi controller and change its overshoot. Subsequently, when the vehicle is operating normally, the vehicle can be braked by the second preset pi controller. When the vehicle speed is low, it is controlled by the first preset pi controller. Since the kp parameter and ki parameter of the first preset pi controller are adjusted accordingly according to the damping coefficient of the vehicle shock absorber, the preset braking response time of the first preset pi controller can also be used under the condition of ensuring the safe braking response of the second preset pi controller when the car is driving normally, which flexibly offsets the obvious front and rear pitching of the vehicle when braking due to the actual soft suspension of the vehicle, greatly improving the user's driving experience.

[0012] In one embodiment of a vehicle braking control method provided by the present invention, determining a current deceleration of the vehicle and performing braking control on the vehicle includes:

[0013] When the speed of the vehicle is lower than a first preset value, obtaining the current slope value of the vehicle;

[0014] Obtaining a feedforward compensation torque according to the slope value, the target deceleration and the current vehicle speed;

[0015] The vehicle is braked in combination with the feedforward compensation torque and the current deceleration.

[0016] The technical solution disclosed in the present invention has at least the following beneficial effects:

[0017] Taking into account that when the vehicle speed is low, the data obtained itself has a large deviation, and therefore the estimated deviation of the vehicle's target deceleration is also large. In order to ensure the safety of the braking tail section, the present invention obtains the slope value of the vehicle when the vehicle speed is lower than a first preset value, and obtains a feedforward compensation torque based on the slope value, the target deceleration and the current vehicle speed. Finally, the vehicle is braked in combination with the feedforward compensation torque and the current deceleration. The brake control is more precise by combining the feedforward compensation torque obtained with the slope value.

[0018] In one embodiment of a vehicle braking control method provided by the present invention, obtaining the current slope value of the vehicle includes:

[0019] Acquire the current longitudinal accelerator signal of the vehicle, and perform low-pass filtering on the signal to obtain a target signal;

[0020] The ratio of the current target signal to the preset value is used as the current slope value of the vehicle.

[0021] The technical solution disclosed in the present invention has at least the following beneficial effects:

[0022] The current longitudinal accelerator signal of the vehicle is obtained, and the signal is low-pass filtered to remove burrs in the signal, thereby obtaining a target signal, and then the current target signal is divided by a preset value to conveniently obtain the current slope value of the vehicle.

[0023] In one embodiment of a vehicle braking control method provided by the present invention, combining the feedforward compensation torque and the current deceleration to perform a braking response on the vehicle includes:

[0024] The target braking torque is obtained by combining the feedforward compensation torque and the current deceleration, and the target braking torque is used to perform a braking response on the vehicle. The formula for obtaining the target braking torque is as follows:

[0025] Torque=m*a*r+ΔTorque

[0026] Among them, m represents the vehicle mass, a represents the current deceleration, r represents the vehicle wheel radius, and ΔTorque represents the feedforward compensation torque.

[0027] The technical solution disclosed in the present invention has at least the following beneficial effects:

[0028] By combining the feedforward compensation torque with the torque obtained by multiplying the current reducer and vehicle mass and wheel radius, a more accurate target braking torque can be obtained when the vehicle speed is low.

[0029] At least one embodiment of the present invention further provides a vehicle braking control system, comprising:

[0030] A tuning module, determining a kp parameter and a ki parameter of a first preset pi controller according to a damping coefficient of a vehicle shock absorber, so as to achieve a preset braking response time;

[0031] a first control module, when the vehicle speed is lower than a first preset value and the target deceleration of the vehicle is lower than a second preset value, using a first preset pi controller to determine the current deceleration of the vehicle based on the preset braking response time and perform braking control on the vehicle;

[0032] The second control module determines the current deceleration of the vehicle and performs braking control on the vehicle by using a second preset PI controller when the vehicle speed is not lower than a first preset value or the target deceleration of the vehicle is not lower than a second preset value.

[0033] In one embodiment of a vehicle braking control system provided by the present invention, the first control module and the second control module further include:

[0034] A slope acquisition unit, when the vehicle speed is lower than a first preset value, acquires the current slope value of the vehicle;

[0035] A feedforward compensation torque acquisition unit, which obtains the feedforward compensation torque according to the slope value, the target deceleration and the current vehicle speed;

[0036] The braking control unit performs braking control on the vehicle in combination with the feedforward compensation torque and the current deceleration.

[0037] In one embodiment of a vehicle braking control system provided by the present invention, the slope acquisition unit includes:

[0038] Acquire the current longitudinal accelerator signal of the vehicle, and perform low-pass filtering on the signal to obtain a target signal;

[0039] The ratio of the current target signal to the preset value is used as the current slope value of the vehicle.

[0040] In one embodiment of a vehicle braking control system provided by the present invention, the braking control unit includes:

[0041] The target braking torque is obtained by combining the feedforward compensation torque and the current deceleration, and the target braking torque is used to perform a braking response on the vehicle. The formula for obtaining the target braking torque is as follows:

[0042] Torque=m*a*r+ΔTorque

[0043] Among them, m represents the vehicle mass, a represents the current deceleration, r represents the vehicle wheel radius, and ΔTorque represents the feedforward compensation torque.

[0044] The present invention also provides a computer-readable storage medium, in which instructions are stored. When the instructions are executed on a terminal device, the terminal device executes a vehicle braking control method as described above.

[0045] The present invention also provides an electronic device, comprising a memory, a processor, and a program stored in the memory and running on the processor, wherein the processor implements the above-mentioned vehicle braking control method when executing the program. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 A schematic flow chart of a vehicle braking control method according to the present invention;

[0047] Figure 2 This is the logic diagram of the pi controller;

[0048] Figure 3 The present invention is a schematic flow chart of a vehicle braking control system. DETAILED DESCRIPTION

[0049] The principles and features of the present invention are described below. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0050] The present invention provides a vehicle braking control method, please refer to Figure 1 As shown, including:

[0051] Determining a kp parameter and a ki parameter of a first preset pi controller according to a damping coefficient of a vehicle shock absorber to achieve a preset braking response time;

[0052] When the vehicle speed is lower than a first preset value and the target deceleration of the vehicle is lower than a second preset value, using a first preset pi controller to determine the current deceleration of the vehicle based on the preset braking response time and perform braking control on the vehicle;

[0053] When the vehicle speed is not lower than the first preset value or the target deceleration of the vehicle is not lower than the second preset value, the second preset pi controller is used to determine the current deceleration of the vehicle and perform braking control on the vehicle.

[0054] According to the damping coefficient of the vehicle shock absorber, when the suspension of the vehicle chassis is soft, the kp parameter and ki parameter of the first preset pi controller can be adjusted to change the response time of the first preset pi controller and change its overshoot. Subsequently, when the vehicle is operating normally, the vehicle can be braked by the second preset pi controller. When the vehicle speed is low, it is controlled by the first preset pi controller. Since the kp parameter and ki parameter of the first preset pi controller are adjusted accordingly according to the damping coefficient of the vehicle shock absorber, the preset braking response time of the first preset pi controller can also be used under the condition of ensuring the safe braking response of the second preset pi controller when the car is driving normally, which flexibly offsets the obvious front and rear pitching of the vehicle when braking due to the actual soft suspension of the vehicle, greatly improving the user's driving experience.

[0055] That is, the present invention is based on the vehicle chassis suspension style, usually by adjusting the damping coefficient of the vehicle shock absorber to make the vehicle chassis suspension harder or softer, and the target deceleration requested by the upstream is reasonably responded to in segments. For example, the first preset value in this example is 0.5km / h, and the second preset value is 0.2m / s^2. When the vehicle speed is in the range of 0ˉ-0.2m / s^2 and the target decelerator is 0.2m / s^2, a separate set of PI control is adopted, that is, the first preset PI controller is used to perform braking control on the vehicle, wherein the logic of the PI controller is as follows Figure 2Shown

[0056] The input of pi control is the error between the target command value and the actual measured value. P is the proportional link, kp is the proportional coefficient; I is the integral link, ki is the integral coefficient. The principle of pi control is to output the error through proportional amplification and cumulative calculation. Pi control takes into account the rapidity of p controller and the stability of i controller.

[0057] According to the "soft and hard" performance of the vehicle chassis suspension, the ki parameter and kp parameter of the first preset pi controller can be appropriately adjusted to achieve the purpose of insufficient response or overshoot to improve the driving experience required by some braking scenarios. For example, when the chassis suspension is soft, the pitch of the vehicle after braking is more obvious, and the kp parameter and ki parameter of the first preset pi controller can be appropriately reduced to extend the response time and reduce the overshoot to achieve the overall braking response effect; on the contrary, when the chassis suspension is hard, the kp parameter and ki parameter of the first preset pi controller can be appropriately increased to shorten the response time. At this time, the overshoot will increase and the overall braking response effect will be overshoot.

[0058] Further, determining the current deceleration of the vehicle and performing braking control on the vehicle includes:

[0059] When the speed of the vehicle is lower than a first preset value, obtaining the current slope value of the vehicle;

[0060] Obtaining a feedforward compensation torque according to the slope value, the target deceleration and the current vehicle speed;

[0061] The vehicle is braked in combination with the feedforward compensation torque and the current deceleration.

[0062] Taking into account that when the vehicle speed is low, the data obtained itself has a large deviation, and therefore the estimated deviation of the vehicle's target deceleration is also large. In order to ensure the safety of the braking tail section, the present invention obtains the slope value of the vehicle when the vehicle speed is lower than a first preset value, and obtains a feedforward compensation torque based on the slope value, the target deceleration and the current vehicle speed. Finally, the vehicle is braked in combination with the feedforward compensation torque and the current deceleration. The brake control is more precise by combining the feedforward compensation torque obtained with the slope value.

[0063] Furthermore, the current slope value of the vehicle is obtained, including:

[0064] Acquire the current longitudinal accelerator signal of the vehicle, and perform low-pass filtering on the signal to obtain a target signal;

[0065] The ratio of the current target signal to a preset value, in this embodiment, the preset value is 10, is used as the current slope value of the vehicle.

[0066] The current longitudinal accelerator signal of the vehicle is obtained, and the signal is low-pass filtered to remove burrs in the signal, thereby obtaining a target signal, and then the current target signal is divided by a preset value to conveniently obtain the current slope value of the vehicle.

[0067] Further, combining the feedforward compensation torque and the current deceleration, performing a braking response on the vehicle includes:

[0068] The target braking torque is obtained by combining the feedforward compensation torque and the current deceleration, and the target braking torque is used to perform a braking response on the vehicle. The formula for obtaining the target braking torque is as follows:

[0069] Torque=m*a*r+ΔTorque

[0070] Among them, m represents the vehicle mass, a represents the current deceleration, r represents the vehicle wheel radius, and ΔTorque represents the feedforward compensation torque.

[0071] By combining the feedforward compensation torque with the torque obtained by multiplying the current reducer and vehicle mass and wheel radius, a more accurate target braking torque can be obtained when the vehicle speed is low.

[0072] Through the above method, the prior art does not classify chassis braking. The present invention can perform a "customized" response according to the vehicle braking scenario, using a segmented response method, that is, targeting the vehicle speed and target deceleration, using the first preset PI controller and the second preset PI controller to optimize the vehicle's braking safety and driving experience.

[0073] The control logic of this method is simple, no additional hardware is needed on the existing technical solution of the vehicle, the cost is low, but the control effect is obvious;

[0074] This method can be combined with existing chassis control logic and algorithms with small changes to improve control effects. The present invention solves the problem that the braking response cannot be flexibly adjusted under the same set of control methods, and innovatively adopts segmented control to improve the driving experience and safety of chassis braking.

[0075] The present invention also provides a vehicle braking control system, please refer to Figure 3 As shown, including:

[0076] A tuning module, determining a kp parameter and a ki parameter of a first preset pi controller according to a damping coefficient of a vehicle shock absorber, so as to achieve a preset braking response time;

[0077] a first control module, when the vehicle speed is lower than a first preset value and the target deceleration of the vehicle is lower than a second preset value, using a first preset pi controller to determine the current deceleration of the vehicle based on the preset braking response time and perform braking control on the vehicle;

[0078] The second control module determines the current deceleration of the vehicle and performs braking control on the vehicle by using a second preset PI controller when the vehicle speed is not lower than a first preset value or the target deceleration of the vehicle is not lower than a second preset value.

[0079] Furthermore, the first control module and the second control module further include:

[0080] A slope acquisition unit, when the vehicle speed is lower than a first preset value, acquires the current slope value of the vehicle;

[0081] A feedforward compensation torque acquisition unit, which obtains the feedforward compensation torque according to the slope value, the target deceleration and the current vehicle speed;

[0082] The braking control unit performs braking control on the vehicle in combination with the feedforward compensation torque and the current deceleration.

[0083] Furthermore, the slope acquisition unit includes:

[0084] Acquire the current longitudinal accelerator signal of the vehicle, and perform low-pass filtering on the signal to obtain a target signal;

[0085] The ratio of the current target signal to the preset value is used as the current slope value of the vehicle.

[0086] Furthermore, the brake control unit comprises:

[0087] The target braking torque is obtained by combining the feedforward compensation torque and the current deceleration, and the target braking torque is used to perform a braking response on the vehicle. The formula for obtaining the target braking torque is as follows:

[0088] Torque=m*a*r+ΔTorque

[0089] Among them, m represents the vehicle mass, a represents the current deceleration, r represents the vehicle wheel radius, and ΔTorque represents the feedforward compensation torque.

[0090] The present invention also provides a computer-readable storage medium, in which instructions are stored. When the instructions are executed on a terminal device, the terminal device executes a vehicle braking control method as described above.

[0091] The present invention also provides an electronic device, comprising a memory, a processor, and a program stored in the memory and running on the processor, wherein the processor implements the above-mentioned vehicle braking control method when executing the program.

[0092] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0093] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A vehicle braking control method, characterized in that: include: Determining a kp parameter and a ki parameter of a first preset pi controller according to a damping coefficient of a vehicle shock absorber to achieve a preset braking response time; When the vehicle speed is lower than a first preset value and the target deceleration of the vehicle is lower than a second preset value, using a first preset pi controller to determine the current deceleration of the vehicle based on the preset braking response time and perform braking control on the vehicle; When the vehicle speed is not lower than the first preset value or the target deceleration of the vehicle is not lower than the second preset value, the second preset pi controller is used to determine the current deceleration of the vehicle and perform braking control on the vehicle.

2. A vehicle braking control method according to claim 1, characterized in that: Determine the current deceleration of the vehicle and apply braking control to the vehicle, including: When the speed of the vehicle is lower than a first preset value, obtaining the current slope value of the vehicle; Obtaining a feedforward compensation torque according to the slope value, the target deceleration and the current vehicle speed; The vehicle is braked in combination with the feedforward compensation torque and the current deceleration.

3. A vehicle braking control method according to claim 2, characterized in that: Get the current slope value of the vehicle, including: Acquire the current longitudinal accelerator signal of the vehicle, and perform low-pass filtering on the signal to obtain a target signal; The ratio of the current target signal to the preset value is used as the current slope value of the vehicle.

4. A vehicle braking control method according to claim 3, characterized in that: Combining the feedforward compensation torque and the current deceleration, performing a braking response on the vehicle includes: The target braking torque is obtained by combining the feedforward compensation torque and the current deceleration, and the target braking torque is used to perform a braking response on the vehicle. The formula for obtaining the target braking torque is as follows: Torque=m*a*r+ΔTorque Among them, m represents the vehicle mass, a represents the current deceleration, r represents the vehicle wheel radius, and ΔTorque represents the feedforward compensation torque.

5. A vehicle braking control system, characterized in that: include: A tuning module, determining a kp parameter and a ki parameter of a first preset pi controller according to a damping coefficient of a vehicle shock absorber, so as to achieve a preset braking response time; a first control module, when the vehicle speed is lower than a first preset value and the target deceleration of the vehicle is lower than a second preset value, using a first preset pi controller to determine the current deceleration of the vehicle based on the preset braking response time and perform braking control on the vehicle; The second control module determines the current deceleration of the vehicle and performs braking control on the vehicle by using a second preset PI controller when the vehicle speed is not lower than a first preset value or the target deceleration of the vehicle is not lower than a second preset value.

6. A vehicle braking control system according to claim 5, characterized in that: The first control module and the second control module further include: A slope acquisition unit, when the vehicle speed is lower than a first preset value, acquires the current slope value of the vehicle; A feedforward compensation torque acquisition unit, which obtains the feedforward compensation torque according to the slope value, the target deceleration and the current vehicle speed; The braking control unit performs braking control on the vehicle in combination with the feedforward compensation torque and the current deceleration.

7. A vehicle braking control system according to claim 6, characterized in that: The slope acquisition unit comprises: Acquire the current longitudinal accelerator signal of the vehicle, and perform low-pass filtering on the signal to obtain a target signal; The ratio of the current target signal to the preset value is used as the current slope value of the vehicle.

8. A vehicle braking control system according to claim 7, characterized in that: The brake control unit comprises: The target braking torque is obtained by combining the feedforward compensation torque and the current deceleration, and the target braking torque is used to perform a braking response on the vehicle. The formula for obtaining the target braking torque is as follows: Torque=m*a*r+ΔTorque Among them, m represents the vehicle mass, a represents the current deceleration, r represents the vehicle wheel radius, and ΔTorque represents the feedforward compensation torque.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores instructions, and when the instructions are executed on a terminal device, the terminal device executes a vehicle braking control method as described in any one of claims 1 to 4.

10. An electronic device comprising a memory, a processor, and a program stored in the memory and running on the processor, characterized in that: When the processor executes the program, the vehicle braking control method according to any one of claims 1 to 4 is implemented.

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