Vehicle control system, control method, controller, brake system, vehicle, and storage medium

Abstract

The invention provides a vehicle control system, a control method, a controller, a vehicle, a brake system, a storage medium and a program product. A control system of a vehicle according to the present application includes: a first controller configured to transmit a parking brake request to a second controller when a driving operation releases an accelerator pedal of the vehicle without applying a driving operation to a brake pedal and a vehicle speed is less than a speed threshold; the second controller is configured to respond to the parking braking request and increase a target braking force at a first increasing speed until the target braking force reaches a preset braking force threshold value; after the target braking force reaches the preset braking force threshold value, the target braking force is kept unchanged until the vehicle speed indicates that the vehicle stops; and after the vehicle is stopped, increasing a target braking force at a second acceleration that is greater than the first acceleration.

Description

Technical Field

[0001] The present application relates to vehicle-related technologies, and more particularly, to technologies related to vehicle braking control. Background Art

[0002] For vehicles operating in single-pedal mode, when the driver releases the accelerator pedal, the electric vehicle's motor works as a generator. At this time, mechanical energy is converted into electrical energy and stored in the vehicle battery to achieve resource regeneration. In this process, the motor working as a generator generates negative torque that slows down the vehicle and achieves braking. However, once the vehicle speed drops to a certain level, or the vehicle's regenerative capacity is limited, the vehicle's friction brake will take over the vehicle's braking. Friction braking refers to the vehicle's braking mechanism braking the wheels through friction between the wheels, which can be hydraulic or mechanical braking.

[0003] Currently, after the vehicle controller VCU issues a parking brake request, the vehicle will change from deceleration braking during resource regeneration to friction braking, causing fluctuations in the vehicle's longitudinal acceleration. At the same time, after the braking system takes over the vehicle's braking, it will change the target braking force depending on whether the vehicle is stationary. The increase in target braking force is likely to cause discomfort to passengers. Summary of the invention

[0004] The control method for a vehicle provided according to the embodiments of the present application can be used to solve at least one of the above-mentioned problems, such as alleviating driving or riding discomfort.

[0005] According to the control system of the vehicle of the example of the present application, the vehicle includes a single-pedal mode, and the control system includes a first controller and a second controller. The first controller is configured to send a parking brake request to the second controller when the driving operation releases the vehicle's accelerator pedal without applying a driving operation to the brake pedal and the vehicle speed is less than a speed threshold; the second controller is configured to increase the target braking force at a first acceleration rate in response to the parking brake request until the target braking force reaches a preset braking force threshold; after the target braking force reaches the preset braking force threshold, keep the target braking force unchanged until the vehicle speed indicates that the vehicle has stopped; and after the vehicle stops, increase the target braking force at a second acceleration rate greater than the first acceleration rate.

[0006] The control system for the vehicle, optionally, the second controller is configured to increase the target braking force at a first increasing rate until the target braking force reaches a preset braking force threshold by: increasing the target braking force at a first group of increasing rates within a first time period until the target braking force reaches a preset braking force threshold, wherein the first time period includes N time periods, the first group of increasing rates includes N increasing rates corresponding to the N time periods, and the target braking force is increased at an i-th increasing rate in the i-th time period, wherein N≥i≥1 and i and N are both integers, the i+1 time period is adjacent to the i-th time period, and the increasing rate of the i+1 time period is greater than the increasing rate of the i-th time period.

[0007] In the control system for a vehicle, optionally, the first controller is configured to receive input signals from a brake pedal and an accelerator pedal of the vehicle; and to receive a signal indicating a wheel speed or a signal indicating a vehicle speed transmitted by a related component.

[0008] In the control system for a vehicle, optionally, the second controller is arranged in the braking system of the vehicle and / or the second controller can be configured in a vehicle controller of the vehicle.

[0009] According to another aspect of the present application, a vehicle control method is also provided, the vehicle including a single-pedal working mode, the method including: in response to a driving operation releasing an accelerator pedal of the vehicle without applying a driving operation to a brake pedal and when a vehicle speed is less than a speed threshold, sending a parking brake request; in response to the parking brake request, increasing a target braking force at a first acceleration until the target braking force reaches a preset braking force threshold; after the target braking force reaches the preset braking force threshold, maintaining the target braking force unchanged until the vehicle speed indicates that the vehicle has stopped; and after the vehicle stops, increasing the target braking force at a second acceleration greater than the first acceleration.

[0010] The control method for a vehicle, optionally, increases the target braking force with a first acceleration until the target braking force reaches a preset braking force threshold, comprising: increasing the target braking force with a first group of accelerations within a first time period until the target braking force reaches a preset braking force threshold, wherein the first time period includes N time periods, the first group of accelerations includes N accelerations corresponding to the N time periods, and the target braking force is increased with an i-th acceleration in the i-th time period, wherein N≥i≥1 and i and N are both integers, the i+1 time period is adjacent to the i-th time period, and the acceleration of the i+1 time period is greater than the acceleration of the i-th time period.

[0011] The control method for a vehicle may optionally include: receiving a signal representing a driving operation on a brake pedal and an accelerator pedal of the vehicle; and receiving a wheel speed signal or a signal representing a vehicle speed.

[0012] According to another aspect of the present application, a controller is also provided. The controller may be configured to receive a parking brake request; in response to the parking brake request, increase the target braking force at a first acceleration until the target braking force reaches a preset braking force threshold; after the target braking force reaches the preset braking force threshold, keep the target braking force unchanged until the vehicle speed indicates that the vehicle has stopped; and after the vehicle has stopped, increase the target braking force at a second acceleration greater than the first acceleration.

[0013] The controller may optionally be configured to increase the target braking force at a first increasing rate until the target braking force reaches a preset braking force threshold by: increasing the target braking force at a first group of increasing rates within a first time period until the target braking force reaches a preset braking force threshold, wherein the first time period includes N time periods, the first group of increasing rates includes N increasing rates corresponding to the N time periods, and the target braking force is increased at an i-th increasing rate in the i-th time period, wherein N≥i≥1 and i and N are both integers, the i+1 time period is adjacent to the i-th time period, and the increasing rate of the i+1 time period is greater than the increasing rate of the i-th time period.

[0014] According to another aspect of the present application, a controller for a vehicle is also provided, the vehicle including a single-pedal mode. The controller is configured to execute a control method for a vehicle described in any example of the present application.

[0015] According to some aspects of the present application, a braking system is also provided, which includes the controller described in the present application.

[0016] According to another aspect of the present application, a non-temporary storage medium is also provided, on which one or more programs are stored, and when the programs are executed by a processor, the control method for a vehicle described in any example of the present application is implemented.

[0017] A computer program product is also provided. The program product includes one or more programs. When the program is executed by a processor, the control method for a vehicle described in any example of the present application is implemented.

[0018] A vehicle is also provided, which includes a control system for a vehicle described according to any example of the present application, or is configured to execute a control method for a vehicle described according to any example of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram of a control system for a vehicle according to some embodiments of the present application;

[0020] Figure 2 is a flow chart of a control method according to some examples of the present application;

[0021] Figure 3 is a schematic diagram of the structure of a controller according to some embodiments of the present application;

[0022] Figure 4 is a schematic diagram of changes in vehicle speed, parking brake request, vehicle state, and actual braking force of a vehicle within the same period of time according to some embodiments of the present application;

[0023] Figure 5 is a schematic diagram of a relationship curve between a parking brake request of a vehicle, a process of a braking system determining a target braking force, a target brake holding pressure, an actual braking force of a wheel, and a longitudinal acceleration of the vehicle when the vehicle does not implement or adopt the embodiment according to the present application;

[0024] Figure 6 It is a schematic diagram of the relationship curve between the vehicle's parking brake request, the process of the braking system determining the target braking force, the target braking holding pressure, the actual braking force of the wheel, and the longitudinal acceleration of the vehicle after the vehicle implements or adopts the embodiment according to the present application. DETAILED DESCRIPTION

[0025] In order to help those skilled in the art to more accurately understand the subject matter for which protection is sought in the present application, the specific implementation of the present application will be described in detail below in conjunction with the accompanying drawings.

[0026] The vehicle described in the following embodiments of the present application has a single-pedal mode. In the single-pedal mode, when the accelerator pedal is pressed, the vehicle accelerates; when the accelerator pedal is released, the regenerative braking system works to reduce the vehicle speed while regenerating energy. It should be noted that the vehicle with a single-pedal mode can still be provided with a brake pedal, rather than eliminating the brake pedal and only providing an accelerator pedal.

[0027] In the example of the present application, the brake system can be a kind of in hydraulic brake system, mechanical brake system or other possible brake system.In addition, although the present application is described with braking force as parameter, it should be understood that braking force can be adopted equally.

[0028] Figure 1 is a schematic diagram of a control system for a vehicle according to some embodiments of the present application. Figure 1As shown, the control system includes a first controller 10 and a second controller 20. The first controller 10 is configured to send a parking brake request to the second controller 20 when the driving operation releases the accelerator pedal of the vehicle without applying the driving operation to the brake pedal and the vehicle speed is less than the speed threshold. Less than the speed threshold in this application may include the vehicle speed being equal to the speed threshold. The second controller 20 receives the parking brake request and, in response, increases the target braking force at a first acceleration until the target braking force reaches a preset braking force threshold; after the target braking force reaches the preset braking force threshold, keeps the target braking force unchanged until it is determined that the vehicle stops; and after the vehicle stops, increases the target braking force at a second acceleration greater than the first acceleration.

[0029] The driving operation may be an operation of the driver on the vehicle, or an operation implemented by the driving system under automatic driving. The driving operation is any one of the operations of stepping on the accelerator pedal, releasing the accelerator pedal, stepping on the brake pedal, and releasing the brake pedal. For a vehicle in single-pedal mode, the process of releasing the accelerator pedal is the deceleration process of the vehicle. In the embodiment of the present application, it is also referred to as the deceleration braking of the vehicle to distinguish it from the friction braking implemented by the vehicle braking system. In the example of the present application, the braking system refers to a braking system that applies braking force to the wheels to stop the vehicle by hydraulic, mechanical, etc. According to some embodiments of the present application, the first controller 10 receives signals from the accelerator pedal and the brake pedal, which are the accelerator pedal signal 42 and the brake pedal signal 44, respectively. The first controller 10 also obtains the vehicle speed. The vehicle speed can be obtained in different ways. For example, the first controller 10 can obtain the sensed wheel speed from the wheel speed sensor and calculate the real-time vehicle speed according to the wheel speed, or the first controller 10 can obtain the vehicle speed from a system that has calculated the vehicle speed in the vehicle (such as the vehicle stability program ESP). Based on the analysis of the signals 42 and 44 , the first controller 10 sends a parking brake request to the second controller 20 when it determines that the accelerator pedal of the vehicle is released and no driving operation is applied to the brake pedal and that the acquired vehicle speed is less than a speed threshold.

[0030] In this article, the increasing rate of the target braking force refers to the rate of change of the target braking force over time, indicating how fast the target braking force changes, and is also called the target braking force gradient.

[0031] In a further embodiment, the first acceleration is a first group of accelerations, including a plurality of different accelerations, and the second controller 20 increases the target braking force at the first group of accelerations within a first duration until the target braking force reaches a preset braking force threshold. The first duration includes N time periods, the first group of accelerations includes N accelerations corresponding to the N time periods, and the target braking force is increased at the i-th time period acceleration in the i-th time period, wherein N≥i≥1 and is an integer, the i+1 time period is adjacent to the i-th time period, and the i+1 time period acceleration is greater than the i-th time period acceleration.

[0032] Take i as 2 as an example. The first duration accordingly includes the first period and the second period. In the first period, the second controller 20 increases the target braking force at the first period acceleration, and in the second period, the second controller 20 increases the target braking force at the second period acceleration until the target braking force reaches the preset braking force threshold. The duration of the first period and the second period, as well as the magnitude of the acceleration, can be determined in advance based on vehicle test data and driving data. In this example, the second acceleration is greater than the first acceleration.

[0033] After the target braking force reaches the preset braking force threshold, the second controller 20 keeps the target braking force unchanged, and accordingly, the actual braking force applied to the wheel also remains basically unchanged. During the period when the target braking force remains unchanged, the driving torque of the vehicle decreases, and the vehicle tends to and eventually stops. After determining that the vehicle is stationary, the second controller 20 increases the target braking force with a second acceleration. Determining that the vehicle is stationary can be determined by the wheel speed and / or vehicle speed of the vehicle. It can be understood that the wheel speed and / or vehicle speed of the vehicle are zero, which does not ensure that the state of the vehicle is necessarily stationary. In the example of the present application, when it is detected that the vehicle speed is zero and / or the wheel speed is zero for a period of time, it is determined that the vehicle is stationary, and the duration is, for example, any time period from 100 to 300 milliseconds. The second acceleration can be greater than all the accelerations within the first time period, that is, the second acceleration can be greater than the acceleration of any i-th time period. The target braking force increased according to the second acceleration is applied to the wheel by the braking mechanism of the vehicle braking system to ensure that the vehicle remains stationary.

[0034] In the example of the present application, the second controller 20 may obtain the vehicle speed through the first controller 10. Alternatively, the second controller 20 may obtain the vehicle speed directly through a wheel speed sensor, or through a system in the vehicle that has calculated the vehicle speed (such as a vehicle stability program ESP). The present application does not limit this.

[0035] In the Figure 1When the control system is applied to a vehicle, the first controller 10 and the second controller 20 can be independently set controllers, respectively, and are configured to communicate with the vehicle controller, brake system and other related components or systems of the vehicle to receive and send signals. As an example, the first controller 10 and the second controller 20 can be electronic controllers including a processor and an associated memory, respectively, and the memory stores computer executable instructions, which, when executed by the processor, cause the processor to perform the operations to be implemented by each controller described herein, thereby implementing any of the embodiments described above in conjunction with the accompanying drawings. The processor can be, but is not limited to, a single processor or multi-processor system of any architecture in a variety of possible architectures, including field programmable gate arrays (FPGAs), central processing units (CPUs), application specific integrated circuits (ASICs), digital signal processors (DSPs) or graphics processing units (GPUs) hardware arranged in a homogeneous or heterogeneous manner. The memory can be, but is not limited to, random access memory (RAM), read-only memory (ROM) or other electronic, optical, magnetic or any other computer-readable medium.

[0036] Alternatively, the first controller 10 may be implemented in a vehicle controller of the vehicle, for example, the instructions for implementing various operations of the first controller 10 are stored so as to be executable by the vehicle controller. The second controller 20 may be arranged in a braking system of the vehicle, for example, the instructions for implementing various operations of the second controller 10 are stored so as to be executable by the braking system. Alternatively, the second controller 20 may be arranged in a vehicle controller of the vehicle.

[0037] Figure 2 is a flow chart of a control method according to some examples of the present application. By way of example and not limitation, the method may be, for example, Figure 1 The control system shown in the figure is executed, or the vehicle controller and the execution system of the vehicle cooperate to execute the method. The following takes the vehicle controller and the braking system to execute the method as an example.

[0038] In step S200, in response to the driving operation releasing the vehicle accelerator pedal without applying the driving operation to the brake pedal and the vehicle speed is less than the speed threshold, a parking brake request is sent. The vehicle controller VCU receives the accelerator pedal signal 42 and the brake pedal signal 44 and analyzes them. The vehicle controller VCU obtains the vehicle speed, and the method of obtaining the vehicle speed is the same as that described above in conjunction with the attached figure. Figure 1 When it is determined based on the accelerator pedal signal 42 and the brake pedal signal 44 that the driving operation releases the accelerator pedal of the vehicle without applying the driving operation to the brake pedal and the acquired vehicle speed is less than the speed threshold, the VCU issues a parking brake request to the brake system.

[0039] In step S202, in response to the parking brake request, the target braking force is increased at a first increasing rate until the target braking force reaches a preset braking force threshold; after the target braking force reaches the preset braking force threshold, the target braking force is kept unchanged until the vehicle speed indicates that the vehicle stops; and after the vehicle stops, the target braking force is increased at a second increasing rate greater than the first increasing rate. The braking system, or more specifically, the braking controller of the braking system, after receiving the parking brake request, increases the target braking force at a first increasing rate until the target braking force reaches the preset braking force threshold. In some examples, the braking controller increases the target braking force at a first group of increasing rates within a first time length until the target braking force reaches the preset braking force threshold. The first time length includes N time periods, and the first group of increasing rates includes N increasing rates corresponding to the N time periods, that is, each time period is provided with an increasing rate, and the target braking force is increased at the i-th time period increasing rate in the i-th time period, wherein N≥i≥1 and N and i are both integers, the i+1 time length is adjacent to the i-th time length, and the i+1-th increasing rate is greater than the i-th increasing rate. A more specific example with i being 2 has been described above, so I will not repeat it here.

[0040] Figure 4 It is a schematic diagram of changes in vehicle speed, parking brake request, vehicle status, and actual braking force of a vehicle in the same time period according to some embodiments of the present application, wherein curve 400 represents the vehicle speed, curve 402 represents the braking request, curve 404 represents whether the vehicle status is stationary or non-stationary, and curve 406 is the actual braking force applied to the wheels. The vehicle adopts a control system according to an embodiment of the present application or executes a control method according to an embodiment of the present application.

[0041] like Figure 4As shown, at time T1, the vehicle speed is reduced to the speed threshold, and the first controller of the vehicle or the vehicle controller issues a parking brake request. The second controller or the brake controller of the braking system increases the target braking force at the first time period acceleration k1, and the target braking force is implemented on the vehicle through the actuator of the braking system, presenting as the actual braking force of the wheel shown in 406. At time T2, the second controller or the brake controller of the braking system increases the target braking force at the second time period acceleration k2, so that the target braking force increases faster, until the target braking force reaches the preset braking force threshold at time T3, and the actual braking force of the wheel also reaches a certain value at this time. From time T3, the second controller or the brake controller keeps the calculated target braking force unchanged, and the actual braking force of the wheel also remains basically unchanged, as shown in curve 406. In the process of the actual braking force of the wheel remaining basically unchanged, after the vehicle speed is detected to be zero at time T4 and continues for a period of time (from time T4 to time T5), it is determined that the vehicle has stopped. From time T5, the second controller or the brake controller of the brake system increases the target braking force rapidly at a second acceleration K3, K3 is greater than K2, and K2 is greater than K1. The rapidly increased target braking force is converted into the actual wheel braking force. According to the present application, after the target braking force increases to a certain extent, it no longer increases, and the vehicle is now firmly stationary.

[0042] According to an example of the present application, a controller is also provided. The controller is configured to receive a parking brake request, and in response to the parking brake request, increase the target braking force at a first acceleration until the target braking force reaches a preset braking force threshold; after the target braking force reaches the preset braking force threshold, keep the target braking force unchanged until the vehicle speed indicates that the vehicle stops; and after the vehicle stops, increase the target braking force at a second acceleration greater than the first acceleration. In a more specific example, the controller is configured to increase the target braking force at a first group of accelerations within a first time length until the target braking force reaches a preset braking force threshold, the first time length includes N time periods, the first group of accelerations includes N accelerations corresponding to the N time periods, and the target braking force is increased at the i-th time period acceleration in the i-th time period, wherein N≥i≥1 and N and i are both integers, the i+1 time length is adjacent to the i-th time length, and the i+1-th acceleration is greater than the i-th acceleration. Figure 3 is an exemplary structure of the controller structure. The controller 3 includes a memory 300 and a processor 302. The memory 300 stores program instructions, and the processor 302 processes the program instructions to implement the functions to be implemented by the controller. The controller 3 can be implemented as, for example Figure 1 The second controller 20 may be implemented as a controller of a braking system, etc.

[0043] According to an example of the present application, a braking system is also provided, which includes, for example, a controller 3 according to an example of the present application.

[0044] According to an example of the present application, a vehicle is also provided. The vehicle includes any one of the control systems described above, or can execute any one of the control methods described above, or includes a controller 3 .

[0045] According to an example of the present application, a non-transitory storage medium is also provided, on which one or more programs are stored. When the programs are executed, any one of the control methods according to the present application is implemented.

[0046] According to an example of the present application, a computer program product is also provided, wherein one or more programs are stored on the program product. When the program is executed, any one of the control methods according to the present application is implemented.

[0047] Figure 5 It is a schematic diagram of the relationship curve between the vehicle's parking brake request, the process of the braking system determining the target braking force, the target brake holding pressure, the actual braking force of the wheel and the longitudinal acceleration of the vehicle when the vehicle does not implement or adopt the embodiment of the present application, wherein the horizontal axis represents time and the vertical axis represents different quantities. Please refer to the description of each curve for details. Figure 5 The example of the vehicle is hydraulically braked. Curve 500 represents the parking brake request signal, curve 502 represents the process of calculating the target braking force, curve 504 represents the target brake holding pressure, curve 506 represents the actual braking force applied to the wheel, and curve 508 represents the change in the longitudinal acceleration of the vehicle.

[0048] like Figure 5As shown, when the vehicle's VCU, for example, issues a parking brake request, the braking system receives the request and calculates the target braking force based on information such as vehicle speed and ramp, and the process is shown in curve 502. When the vehicle is not completely stopped, the calculated target braking force increases in a relatively smooth manner as shown in the first part 502a of curve 502. The braking force is opposite to the driving force in direction, so it is shown as a negative value in N, where the increase rate refers to the increase rate of the absolute value of the braking force, regardless of the direction. The target brake holding pressure (unit: bar, positive value) determined based on the first part 502a is shown as the first part 504a of curve 504, and its increase is also relatively smooth. Correspondingly, the actual braking force acting on the wheel increases slowly and steadily, as shown in the first part 506a of curve 506. At time T5, the vehicle stops. Since the target braking force calculated based on information such as the slope (as shown in the second part 502b of curve 502) is significantly different from the actual wheel braking force that has been formed, the final target holding pressure at this time increases rapidly at a higher rate of increase after time T5 (as shown in the second part 504b of curve 504) to a new holding pressure level (maintained constant). In this process, the actual braking force applied to the wheel also changes at a higher rate of increase, as shown in the second part 506b of curve 506. Since the inflection point of the rate of increase occurs when the vehicle just stops, the vehicle is prone to discomfort caused by changes in the body posture.

[0049] Figure 6 It is a schematic diagram of the relationship curve between the parking brake request of the vehicle, the process of the braking system determining the target braking force, the target brake holding pressure, the actual braking force of the wheel, and the longitudinal acceleration of the vehicle after the vehicle implements or adopts the embodiment according to the present application, wherein the horizontal axis represents time and the vertical axis represents different quantities, and the details can be found in the description of each curve. Curve 600 represents the parking brake request, curve 602 represents the determined target braking force, curve 604 represents the target brake holding pressure, curve 606 represents the actual braking force applied to the wheel, and curve 608 represents the longitudinal acceleration of the vehicle.

[0050] When, for example, the vehicle VCU sends a parking brake request, the braking system that receives the braking request begins to calculate the target braking force based on the vehicle speed, ramp and other information. When the vehicle has not yet completely stopped, in the process of determining the target braking force, its growth rate is relatively smooth, as shown in the first part 602a and the second part 602b of the curve 602, wherein, as a braking force, it is opposite to the direction of the driving force, so it is illustrated as a negative value as shown in the period 602 in the accompanying drawing. The increase in braking force and the rate of increase of braking force discussed here refer to the change in the absolute value of the braking force. According to the example of the present application, in the process of accumulating the target braking force, the gradient of the target braking force can be changed. For example, in the time period from T6 to T7 in the figure, the rate of increase is K1, and in the time period from T7 to T8, the rate of increase is K2, which is reflected in the calculation process as the first part 602a and the second part 602b of the curve 62. In this example, although the acceleration rate is slightly different, corresponding to the calculation process represented by curve 602, the target braking maintaining pressure (as shown by curve 604) in the first part 604a (the target braking maintaining pressure in the time period from T6 to T8) is relatively smooth, and the actual braking force applied to the wheel in the corresponding period (as shown by curve 606) also increases slowly and steadily.

[0051] When the wheel speed drops to a certain threshold, the vehicle may not be completely stationary at this time. When the driving force and the existing braking force reach a balance, a stable pressure holding pressure will be maintained (as shown in the second part 604b of curve 604), which makes the driving force and the actual braking force applied to the wheel end maintain a balance (as shown in the corresponding part 606b of curve 606 corresponding to the second part 604b of curve 604). In this way, keeping the vehicle stationary for a certain period of time can avoid misidentifying the stationary state of the vehicle during dynamic balance as the real stationary state of the vehicle. After this period of time, when it is confirmed that the vehicle is really stationary (at this time, the vehicle has no body pitch), the target braking force calculated based on information such as the slope will be greatly different from the actual pressure formed in the wheel cylinder, and it is necessary to quickly accumulate the target braking force to reach the pressure holding pressure level. Therefore, at this time, according to the present application, the acceleration K3 is used to quickly accumulate the target braking pressure holding pressure to avoid slipping after the driving force is removed. Since the vehicle has been completely stationary for a period of time at this time, when the acceleration K3 is used to quickly increase the pressure, it will not affect the body posture of the stationary vehicle, nor will it cause discomfort due to sudden changes in pressure.

[0052] In addition, the change in longitudinal acceleration ΔAx and its rate of change Jerk can reflect the vehicle body pitch / comfort. Figure 5 The vehicle in the example does not adopt the solution according to the present application. Since the wheel-end braking force increases rapidly in a short period of time, the rate of change changes significantly. For example, in this example, Tp is 183ms, and the absolute value of the rate of change Jerk can reach 3.9m / s3. Figure 6After the solution according to the present application is adopted, the overall time of pressure increase is increased due to the control of the acceleration of the braking force applied to the wheel end, which slows down the pressure increase rate. Therefore, under the premise of a larger longitudinal acceleration change ΔAx, the change of Jerk is weakened. For example, in this example, when Tp is 313ms, the absolute value of the change rate Jerk is reduced to 2.9m / s3, which is significantly lower than Figure 5 The situation before the embodiments according to the present application is not adopted.

[0053] It should be noted that in the examples of the present application combined with the accompanying drawings, the time of each example is not related, such as Figure 4 The moments T1 to T5 in the example are just a continuation of the moments in the example. Figure 5 The T5 moment that appears in Figure 4 The moments in time are irrelevant and are only used to indicate Figure 5 At that point in time, similarly, Figure 6 The times T6, T7 and T8 in the figure also represent Figure 6 The time points of the examples.

[0054] In the absence of contradiction or conflict, the technical features in the examples described herein may be combined with each other to form implementations not described herein, which should also be covered by the scope of this application.

[0055] Although specific embodiments of the present application have been shown and described in detail to illustrate the principles of the present application, it should be understood that the present application may be implemented in other ways without departing from such principles, for example, the technical features of the various embodiments / examples / examples of the present application may be combined with each other to form new implementation methods.

Claims

1. A vehicle control system, characterized in that: The vehicle includes a single pedal mode, the control system includes a first controller and a second controller, The first controller is configured to send a parking brake request to the second controller when the driving operation releases the accelerator pedal of the vehicle without applying the driving operation to the brake pedal and the vehicle speed is less than a speed threshold; The second controller is configured to, in response to the parking brake request, increase the target braking force at a first increasing rate until the target braking force reaches a preset braking force threshold; maintain the target braking force unchanged after the target braking force reaches the preset braking force threshold until the vehicle speed indicates that the vehicle has stopped; and increase the target braking force at a second increasing rate greater than the first increasing rate after the vehicle has stopped.

2. The control system according to claim 1, characterized in that: The second controller is configured to increase the target braking force at a first increasing rate until the target braking force reaches a preset braking force threshold by: The target braking force is increased within a first time period at a first group of increasing speeds until the target braking force reaches a preset braking force threshold; wherein the first time period includes N time periods, the first group of increasing speeds includes N increasing speeds corresponding to the N time periods, and the target braking force is increased at the i-th increasing speed in the i-th time period, wherein N≥i≥1 and i and N are both integers, the i+1 time period is adjacent to the i-th time period, and the increasing speed of the i+1 time period is greater than the increasing speed of the i-th time period. .

3. The control system according to claim 1 or 2, characterized in that: The first controller is configured to receive input signals from a brake pedal and an accelerator pedal of the vehicle, and receive a signal indicating a wheel speed or a signal indicating a vehicle speed transmitted by a related component.

4. The control system according to claim 1 or 2, characterized in that: The second controller is arranged in the braking system of the vehicle and / or the second controller is arranged in the vehicle controller of the vehicle.

5. A vehicle control method, characterized in that: The vehicle includes a single-pedal operating mode, and the method includes: sending a parking brake request in response to a driving operation releasing an accelerator pedal of the vehicle without applying a driving operation to a brake pedal and when a vehicle speed is less than a speed threshold; In response to the parking brake request, the target braking force is increased at a first increasing rate until the target braking force reaches a preset braking force threshold; after the target braking force reaches the preset braking force threshold, the target braking force is maintained unchanged until the vehicle speed indicates that the vehicle has stopped; and after the vehicle has stopped, the target braking force is increased at a second increasing rate that is greater than the first increasing rate.

6. The method according to claim 5, characterized in that Increasing the target braking force at a first increasing rate until the target braking force reaches a preset braking force threshold, comprising: A target braking force is increased within a first time period at a first group of increasing rates until the target braking force reaches a preset braking force threshold, wherein the first time period includes N time periods, the first group of increasing rates includes N increasing rates corresponding to the N time periods, and the target braking force is increased at an i-th increasing rate in the i-th time period, wherein N≥i≥1 and i and N are both integers, the i+1 time period is adjacent to the i-th time period, and the increasing rate of the i+1 time period is greater than the increasing rate of the i-th time period.

7. The method according to claim 5 or 6, characterized in that: The method comprises: receiving a signal indicating a driving operation on a brake pedal and an accelerator pedal of the vehicle; and Receives wheel speed signals or signals indicating vehicle speed.

8. The method according to claims 5 to 7, characterized in that The method is performed by any one of the controllers of the vehicle and the braking system of the vehicle.

9. A controller, characterized in that: The controller is configured as follows: receiving a parking brake request; In response to the parking brake request, the target braking force is increased at a first increasing rate until the target braking force reaches a preset braking force threshold; after the target braking force reaches the preset braking force threshold, the target braking force is maintained unchanged until the vehicle speed indicates that the vehicle has stopped; and after the vehicle has stopped, the target braking force is increased at a second increasing rate that is greater than the first increasing rate.

10. The controller according to claim 9, characterized in that: The controller is configured to increase the target braking force at a first increasing rate until the target braking force reaches a preset braking force threshold by: A target braking force is increased within a first time period at a first group of increasing rates until the target braking force reaches a preset braking force threshold, wherein the first time period includes N time periods, the first group of increasing rates includes N increasing rates corresponding to the N time periods, and the target braking force is increased at an i-th increasing rate in the i-th time period, wherein N≥i≥1 and i and N are both integers, the i+1 time period is adjacent to the i-th time period, and the increasing rate of the i+1 time period is greater than the increasing rate of the i-th time period.

11. A braking system, characterized in that: The braking system comprises a controller according to claim 9 or 10.

12. A vehicle, characterized in that: The vehicle comprises a control system according to any one of claims 1 to 4, or is configured to execute a method according to any one of claims 5 to 7; or comprises a controller according to claim 9 or 10.

13. A non-transitory storage medium, characterized in that: The storage medium stores one or more programs, which implement the method according to any one of claims 5 to 7 when executed by the processor.

14. A computer program product, characterized in that The program product comprises one or more programs, which implement the method according to any one of claims 5 to 7 when executed by a processor.

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