Vehicle braking control method, controller and vehicle

Abstract

The invention provides a vehicle braking control method, a controller and a vehicle, and the vehicle braking control method comprises the following steps: in response to an emergency braking request of the vehicle, controlling a braking caliper of the vehicle to increase a caliper braking torque according to a first rate threshold value, and controlling a motor of the vehicle to increase a regenerative braking torque according to a second rate threshold value, and the wheels of the vehicle are braked. According to the method, during emergency braking, the braking capacity of the motor and the braking calipers is utilized, the braking torque is output to the wheel end through the motor and the braking calipers at the same time through cooperative control in the establishing stage of the braking strength, the purpose of increasing the vehicle braking loading rate is achieved, and therefore the coordination time during emergency braking of the vehicle can be shortened; the vehicle braking distance during emergency braking is shortened, and the braking performance of the vehicle is improved.

Description

Technical Field

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

[0002] Research has found that 90% of drivers react too slowly or not decisively enough during emergency braking, which makes the brake system take a long time to reach the maximum braking force, resulting in a long braking distance and increased driving danger. For this reason, the relevant technology proposes to add a Brake Assist System (BAS) to the vehicle. Although this can help the driver to actuate the vehicle's emergency braking faster, the execution effect of this function depends on the pressure-building capacity of the hydraulic system and cannot shorten the braking coordination time (the time from when the brake pedal starts to act to produce a braking effect to when the wheel braking rate reaches 75% during emergency braking), and cannot improve the braking performance. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art to at least some extent. To this end, the purpose of the present invention is to provide a vehicle braking control method, a controller and a vehicle to reduce the coordination time during emergency braking of the vehicle, shorten the vehicle braking distance during emergency braking, and improve the braking performance of the vehicle.

[0004] To achieve the above-mentioned purpose, an embodiment of the first aspect of the present invention proposes a vehicle braking control method, the method comprising: in response to an emergency braking request of the vehicle, controlling the brake caliper of the vehicle to increase the caliper braking torque according to a first rate threshold, and controlling the motor of the vehicle to increase the regenerative braking torque according to a second rate threshold to brake the wheels of the vehicle.

[0005] In addition, the vehicle braking control method proposed in the embodiment of the present invention may also have the following additional technical features:

[0006] In some embodiments of the present invention, before controlling the brake caliper of the vehicle to increase the caliper braking torque according to a first rate threshold and controlling the motor of the vehicle to increase the regenerative braking torque according to a second rate threshold, the method also includes: determining that the vehicle speed is greater than the first speed threshold.

[0007] In some embodiments of the present invention, after controlling the brake caliper of the vehicle to increase the caliper braking torque according to a first rate threshold and controlling the motor of the vehicle to increase the regenerative braking torque according to a second rate threshold, the method further includes: adjusting the wheel braking force in response to activation of the anti-lock braking system of the vehicle; and performing anti-lock control through the brake caliper when the wheel speed of the vehicle converges to the vehicle speed and the regenerative braking torque is less than or equal to the braking torque threshold.

[0008] In some embodiments of the present invention, the wheel braking force is adjusted in the following manner: the caliper braking torque is kept unchanged, and the motor is controlled to reduce the regenerative braking torque to the braking torque threshold according to a third rate threshold, wherein the third rate threshold is greater than the second rate threshold; or, the brake caliper is controlled to continue to increase the caliper braking torque according to the first rate threshold, and the motor is controlled to reduce the regenerative braking torque to the braking torque threshold according to a fourth rate threshold, wherein the fourth rate threshold is less than the third rate threshold; or, the brake caliper is controlled to reduce the caliper braking torque to the target caliper braking torque, and the motor is controlled to reduce the regenerative braking torque to the braking torque threshold according to the third rate threshold.

[0009] In some embodiments of the present invention, the fourth rate threshold is determined according to the regenerative braking torque, the first rate threshold, the target caliper braking torque and the caliper braking torque.

[0010] In some embodiments of the present invention, the emergency braking request includes: a driver emergency braking request and / or an auxiliary driving system emergency braking request.

[0011] In some embodiments of the present invention, if the brake pedal travel of the vehicle is greater than or equal to a first travel threshold and the rate of increase of the brake pedal travel is greater than or equal to a first rate, the rate of increase of the brake pedal travel is greater than or equal to a second rate, or the brake pedal travel is greater than or equal to a second travel threshold and the brake pedal pressure is greater than a first pressure threshold, wherein the second rate is greater than the first rate.

[0012] In some embodiments of the present invention, if the assisted driving system requests a vehicle deceleration greater than a first deceleration threshold or the assisted driving system enters an emergency braking state in response to an emergency braking command, it is determined that the assisted driving system emergency braking request is obtained.

[0013] In some embodiments of the present invention, the first rate threshold is determined based on the idle travel between the caliper friction pad of the brake caliper and the brake disc of the vehicle, the rate of change of the force applied by the brake caliper between the caliper friction pad and the brake disc, and the friction coefficient between the caliper friction pad and the brake disc; the second rate threshold is determined based on the torque loading rate of the motor and the maximum power that the energy recovery system of the vehicle can withstand.

[0014] In some embodiments of the present invention, the method further includes: if the emergency braking request is obtained and the vehicle speed is greater than the first speed threshold, controlling the vehicle to activate the electro-hydraulic composite brake assist function; if the vehicle speed is less than or equal to the minimum control speed of the anti-lock braking system, the judgment conditions of the emergency braking request are no longer met, or the brake pedal information of the vehicle meets the conditions for triggering the anti-lock braking system, controlling the vehicle to exit the electro-hydraulic composite brake assist function, wherein the minimum control speed is less than the first speed threshold.

[0015] In some embodiments of the present invention, if the brake pedal travel decreases by a third travel threshold, or the brake pedal pressure decreases by a second pressure threshold, it is determined that the determination condition for the emergency braking request is no longer satisfied.

[0016] To achieve the above objectives, a second aspect of the present invention provides a controller, which includes a memory, a processor and a computer program stored in the memory. When the computer program is executed by the processor, the vehicle braking control method of any of the above embodiments is implemented.

[0017] To achieve the above objectives, a third aspect of the present invention provides a vehicle, which includes the controller of the above embodiment.

[0018] According to the vehicle braking control method, controller and vehicle proposed in the embodiments of the present invention, when the vehicle enters an emergency braking state, the braking capacity of the motor and the brake caliper is utilized. In the stage of establishing the braking intensity, through coordinated control, the braking torque is output to the wheel end through the motor and the brake caliper at the same time, so as to achieve the purpose of increasing the braking loading rate of the vehicle, thereby reducing the coordination time of the vehicle during emergency braking, shortening the vehicle braking distance during emergency braking, and improving the braking performance of the vehicle.

[0019] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a flow chart of a vehicle braking control method according to an embodiment of the present invention;

[0021] Figure 2 is a schematic diagram of a system architecture for implementing a vehicle braking control method according to an embodiment of the present invention;

[0022] Figure 3 is a flow chart of a vehicle braking control method according to a specific embodiment of the present invention;

[0023] Figure 4 is a schematic diagram of the architecture of the electro-hydraulic composite brake assist function of an embodiment of the present invention;

[0024] Figure 5 is a schematic diagram of a connection process with ABS control according to an embodiment of the present invention;

[0025] Figure 6 is a schematic diagram of the torque application effect of one embodiment of the present invention;

[0026] Figure 7 is a structural block diagram of a controller according to an embodiment of the present invention;

[0027] Figure 8 4 is a structural block diagram of a vehicle according to an embodiment of the present invention. DETAILED DESCRIPTION

[0028] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0029] The vehicle braking control method, controller and vehicle according to the embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0030] Figure 1 It is a flow chart of a vehicle braking control method in an embodiment of the present invention.

[0031] like Figure 1 As shown, the vehicle braking control method includes:

[0032] S11, responding to an emergency braking request of the vehicle.

[0033] S12, controlling the brake caliper of the vehicle to increase the caliper braking torque according to a first rate threshold.

[0034] The calculation of the first rate threshold can be determined based on the free travel between the friction pad of the brake caliper and the brake disc, the rate of change of the force applied by the brake caliper between the friction pad and the brake disc, and the friction coefficient between the friction pad of the brake caliper and the brake disc.

[0035] S13, controlling the motor of the vehicle to increase the regenerative braking torque according to a second rate threshold.

[0036] The second rate threshold may be determined based on the torque loading rate of the motor, the maximum power that the energy recovery system can withstand, and the like.

[0037] It should be noted that step S12 can achieve braking of the vehicle wheels by hydraulic braking, and step S13 can achieve braking of the vehicle wheels by electric braking, and steps S12 and S13 can be executed simultaneously, regardless of order.

[0038] Specifically, the vehicle's cooperative control component can detect the vehicle's brake pedal travel sensor signal, brake pedal force sensor signal, brake request signal of the Advanced Driver Assistance Systems (ADAS) controller, etc. in real time or periodically, and judge whether the vehicle triggers emergency braking based on this. When the vehicle has an emergency braking request, the vehicle's electro-hydraulic composite brake assist function can be activated, and after the function is activated, the motor and brake caliper are coordinated to quickly increase the vehicle's brake loading rate. Including: increasing the brake caliper's braking torque according to a first rate threshold (which can be the maximum allowable rate at which the brake caliper increases the braking torque), and controlling the motor to increase the regenerative braking torque according to a second rate threshold (which can be the maximum allowable rate at which the motor increases the regenerative braking torque). As a result, the brake caliper and the motor cooperate to brake the wheel, thereby achieving the purpose of increasing the vehicle's brake loading rate, thereby reducing the coordination time during emergency braking of the vehicle, shortening the vehicle's braking distance during emergency braking, and improving the vehicle's braking performance.

[0039] In some embodiments, before controlling the brake caliper of the vehicle to increase the caliper braking torque according to the first rate threshold and controlling the motor of the vehicle to increase the regenerative braking torque according to the second rate threshold, it is necessary to determine that the vehicle speed is greater than the first speed threshold (e.g., 15 km / h). This is because when the vehicle speed reaches a certain level, it is necessary to determine whether the vehicle needs to take strong braking measures to ensure safe driving; and when the vehicle speed is below this level, the maximum braking distance of the vehicle itself is very small, and the vehicle braking loading rate can meet the braking demand even if it is not large, so the coordinated braking of the above step S11 can be omitted.

[0040] In this embodiment, if an emergency braking request is obtained and the vehicle speed is greater than the first speed threshold, the vehicle is controlled to activate the electro-hydraulic composite brake assist function, wherein the electro-hydraulic composite brake assist function is a newly added function of the invention, which is defined by simultaneously performing electric braking and hydraulic braking during emergency braking.

[0041] In some embodiments, after the brake caliper and the motor of the vehicle are controlled to increase the corresponding braking torque according to the first rate threshold and the second rate threshold, the anti-lock braking system of the vehicle may be triggered to activate. At this time, it is necessary to respond to the anti-lock braking system of the vehicle and adjust the wheel braking force to ensure that the braking force of each wheel is as balanced as possible during the braking process to avoid loss of control due to locking of one or more wheels.

[0042] After adjusting the wheel braking force, when the vehicle's wheel speed converges to the vehicle speed and the regenerative braking torque is less than or equal to the braking torque threshold, anti-lock control is performed through the brake caliper. At this time, the braking torque is reduced by using the brake caliper to control the vehicle to prevent the wheel from locking, so that the vehicle can be kept in a stable state and driving safety is improved.

[0043] In the traditional hydraulic braking scheme, when the emergency brake assist is triggered, sufficient braking intensity will eventually cause the wheels to reach critical locking in high-dynamic scenarios. Since the traditional scheme cannot solve the relationship between anti-lock control and regenerative braking well, the vehicle cannot apply a large regenerative braking torque in the case of emergency braking. The anti-lock control proposed by the present invention can effectively connect the two torques of regenerative braking and caliper braking, which can improve the working range of regenerative braking and will not have a negative impact on anti-lock control.

[0044] In the specific implementation process of the present invention, the wheel braking force can be adjusted in a variety of ways. One of them is to keep the caliper braking torque unchanged, and control the motor to reduce the regenerative braking torque to the braking torque threshold according to the third rate threshold; it is also possible to control the brake caliper to continue to increase the caliper braking torque according to the first rate threshold, and control the motor to reduce the regenerative braking torque to the braking torque threshold according to the fourth rate threshold; in addition, it is also possible to control the brake caliper to reduce the caliper braking torque to the target caliper braking torque, and control the motor to reduce the regenerative braking torque to the braking torque threshold according to the third rate threshold.

[0045] In these methods, the fourth rate threshold is determined according to the relationship between the regenerative braking torque, the first rate threshold, the target caliper braking torque and the caliper braking torque. By adjusting the control strategy of the motor and the brake caliper, the energy recovery efficiency of the vehicle is improved as much as possible while ensuring the safety of the vehicle, thereby achieving the purpose of energy saving and environmental protection.

[0046] The anti-lock control proposed in the present invention is the first torque reduction control after the wheel tends to lock, which is mainly achieved by unloading the motor torque. Compared with the traditional hydraulic braking solution, the torque reduction rate of the present invention can be significantly improved (the motor torque unloading time can be ignored compared with the traditional solution), thereby shortening the time for the wheel to return to a steady state, making the ABS function recognize the road surface more quickly and adjusting the control mode more timely.

[0047] In some embodiments, the emergency braking request includes: a driver emergency braking request and / or an auxiliary driving system emergency braking request. When these emergency braking requests occur, it indicates that an unexpected situation has occurred in the vehicle, and corresponding measures can be taken to ensure the safety of the vehicle and its passengers.

[0048] Specifically, when the vehicle's brake pedal travel is greater than or equal to a first travel threshold and the brake pedal travel increase rate is greater than or equal to a first rate, or the brake pedal travel increase rate is greater than or equal to a second rate (where the second rate is greater than the first rate), or the brake pedal travel is greater than or equal to a second travel threshold and the brake pedal pressure is greater than a first pressure threshold, it is determined that the driver's emergency braking request is obtained.

[0049] When the assisted driving system requests the vehicle deceleration to be greater than the first deceleration threshold, or the assisted driving system responds to the emergency braking command and enters the emergency braking state, it is determined that the assisted driving system emergency braking request is obtained.

[0050] For emergency braking, the traditional hydraulic braking solution relies solely on hydraulic pressure to establish braking strength, which limits the vehicle's response processing in different scenarios. The present invention not only determines the driver's request for braking depth, but also determines ADAS and other driving assistance systems. Compared with the traditional solution, it improves the responsiveness of the braking system, thereby better meeting the upper-level control requirements of ADAS.

[0051] In some embodiments, after the electro-hydraulic composite brake assist function is activated, if the vehicle speed is less than or equal to the minimum control speed of the anti-lock braking system, the determination condition of the emergency brake request is no longer met, or the brake pedal information (such as brake pedal travel, brake pedal pressure) meets the conditions for triggering the anti-lock braking system, the vehicle is controlled to exit the electro-hydraulic composite brake assist function. The minimum control speed is less than the first speed threshold.

[0052] Among them, if the brake pedal travel is reduced by a third travel threshold, or the brake pedal pressure is reduced by a second pressure threshold, it is determined that the determination condition for the emergency braking request is no longer met, wherein the third travel threshold is smaller than the first travel threshold and smaller than the second travel threshold, and the second pressure threshold is smaller than the first pressure threshold.

[0053] For ease of understanding, the following Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 A vehicle braking control method according to an embodiment of the present invention is described.

[0054] Figure 2 FIG. 1 is a schematic diagram of a system architecture for implementing a vehicle braking control method according to an embodiment of the present invention. Figure 2 As shown, the system architecture includes a brake pedal travel sensor, a brake pedal force sensor, an ADAS controller, a cooperative control component, a motor, a brake caliper and a wheel.

[0055] Specifically, the motor can generate regenerative braking torque, and finally act on the wheel tire through the transmission, output half shaft and wheel hub; the brake caliper can generate friction braking torque with the brake disc, and finally act on the wheel tire through the wheel hub. The collaborative control component is the functional carrier of the scheme of the present invention, that is, the main body that executes the control method of the present invention, which can be an integrated controller or a collection of multiple controllers, such as a combination of a vehicle control unit (VCU), an electronic vehicle stability control system (ESC) and a motor controller (MCU). These controllers can realize the acquisition of brake pedal travel sensor and brake pedal force sensor signals, can obtain the braking request of the ADAS controller, and can drive the motor to output torque and actuate the brake caliper to clamp.

[0056] Figure 3 This is a flow chart of a vehicle braking control method according to a specific embodiment of the present invention. It mainly includes: emergency braking determination, implementation of the fastest braking response and connection with anti-lock braking control. The specific process is as follows:

[0057] S21, obtaining a brake pedal travel sensor signal, a brake pedal force sensor signal, and a brake request from an ADAS controller.

[0058] S22, judging the acquired signal.

[0059] Specifically, the collaborative control component performs a logical judgment on the signal obtained in step S21, and executes step S23 when the entry conditions of the "electro-hydraulic composite brake assist function" are met.

[0060] S23, controlling the brake caliper to increase the braking torque according to the maximum torque increase rate allowed by the current system, and controlling the motor to increase the regenerative braking torque according to the maximum torque increase rate allowed by the current system.

[0061] S24, periodically obtaining the working status of the anti-lock braking system (ABS) to determine whether the anti-lock braking system is activated.

[0062] Specifically, the cooperative control component periodically obtains the ABS working status, and when the anti-lock braking system is activated, executes step S25.

[0063] S25, adjusting the wheel braking force according to the current levels of the motor regenerative braking force and the caliper braking force.

[0064] Specifically, the ABS function will adjust (reduce) the wheel braking force based on the current levels of motor regenerative braking force and caliper braking force output by the "electro-hydraulic composite brake assist function" at the last moment (ABS is not activated). During the adjustment process, the motor regenerative braking torque will be reduced first until the wheel braking torque reaches a level close to the road adhesion ability.

[0065] S26, determining whether the wheel is in a controlled state and whether the regenerative braking torque output by the motor has dropped below a threshold.

[0066] Specifically, after executing the first torque unloading, the ABS function will judge the state of the wheel end. When the wheel is in a controlled state (the slip trend of the wheel speed is improved, and the wheel speed tends to return to the vehicle speed, that is, converges to the vehicle speed) and the regenerative braking torque output by the motor has dropped below the threshold (such as 0, or a value close to 0), execute step S27.

[0067] S27, ABS function performs anti-lock control of caliper braking force.

[0068] Figure 4 This is a schematic diagram of the architecture of the electro-hydraulic composite brake assist function of an embodiment of the present invention. The "electro-hydraulic composite brake assist function" is mainly composed of three modules: a functional state machine, a signal processing module, and a deceleration control module. The thresholds in this embodiment are only for reference. In actual application, testing and calibration work need to be carried out according to different vehicle parameters and pedal designs to select appropriate thresholds.

[0069] For example, the "electro-hydraulic composite brake assist function" can be activated in the following cases: there is no relevant fault in the system; the vehicle speed is ≥15 kilometers per hour; the driver or the ADAS controller requests emergency braking. Specifically, the judgment principle for the ADAS controller to request emergency braking can select one of the following conditions: ADAS requests vehicle deceleration>8m / s2 or ADAS issues an emergency braking state.

[0070] The signal processing module is mainly responsible for determining whether the driver requests emergency braking, which can be determined based on any of the following conditions: brake pedal travel ≥ 50% and brake pedal increase rate ≥ 800%; brake pedal increase rate ≥ 1000%; brake pedal travel ≥ 50% and brake pedal force greater than 100N.

[0071] The deceleration control module is mainly responsible for controlling the motor and caliper to increase the braking force according to the maximum torque increase rate allowed by the system until the ABS function is triggered or the "electro-hydraulic composite brake assist function" state is no longer activated. This module is also subject to some constraints, such as the brake caliper capacity and the motor regenerative braking capacity. When the vehicle speed is ≤ the minimum control speed of the ABS function, the driver or ADAS controller no longer requests emergency braking, or the driver's input braking request reaches a level that can trigger the ABS, the "electro-hydraulic composite brake assist function" is triggered to exit the activation state.

[0072] In order to avoid frequent activation and exit of the "electro-hydraulic composite brake assist function", the judgment of whether the driver no longer requests emergency braking can be limited by any of the following conditions: when the brake pedal travel decreases by 10% or the brake pedal force decreases by 10N, it is determined that the "electro-hydraulic composite brake assist function" has exited the activated state.

[0073] Figure 5 1 is a schematic diagram of the connection process with ABS control of an embodiment of the present invention. In the braking torque-time relationship diagram, the dark area represents the strength of the motor regenerative braking torque, and the light area on the right represents the strength of the caliper braking torque. (a), (b), and (c) respectively represent different processing strategies executed for different levels of regenerative braking torque and caliper braking torque when the ABS function is activated. The logic of ABS control hydraulic pressure mainly includes the following stages when the wheel tends to lock for the first time: t1 stage (t1a is Figure 5 In (a), the t1 stage and t1b are Figure 5 In the t1 stage of (b), t1c is Figure 5 Phase t1 in (c): Based on parameters such as wheel speed, wheel acceleration and wheel acceleration change rate, the wheel slip state is identified and the braking torque is quickly reduced so that the wheel no longer tends to lock. Phase t2: The braking force is reduced to the estimated level and maintained for a period of time until the wheel is controlled, that is, the wheel speed recovery rate reaches the requirement. Phase t3: After the wheel speed is controlled, further information and state judgment is performed as the control basis for the next pressure increase / pressure relief / pressure maintenance control cycle.

[0074] Specifically, for Figure 5 In (a), when ABS intervenes, the current regenerative braking torque and caliper braking torque are in an ideal state: the caliper braking torque is very close to the target maintained in the first control cycle of ABS, and the deviation between the two is less than a certain range. At this time, the ABS function controls the caliper braking torque to remain unchanged, and reduces the motor regenerative braking torque to 0 at the fastest rate and then enters the t2 stage.

[0075] for Figure 5In (b), when ABS intervenes, the current level of regenerative braking torque is at a relatively large level, and the level of caliper braking torque has a certain gap with the maintenance target of the first control cycle of ABS. The deviation between the two is greater than a certain range. At this time, the ABS function continues to increase the caliper braking torque at the maximum rate allowed by the system, and reduces the motor regenerative braking torque to 0 at a certain rate (i.e., the fourth rate threshold) After the caliper braking torque increases to the target level, it enters the t2 stage.

[0076] The calculation formula of the unloading rate of the motor regenerative braking torque (ie, the fourth rate threshold) is:

[0077]

[0078] for Figure 5 In (c), when ABS intervenes, the current regenerative braking torque level is at a relatively low level, and the caliper braking torque level is a certain gap higher than the maintenance target of the first ABS control cycle. The deviation between the two is greater than a certain range. At this time, the ABS function needs to reduce the motor regenerative braking torque to 0 at the fastest rate and control the caliper braking torque to the target level. After the caliper braking torque is reduced to the target level, it enters the t2 stage.

[0079] It should be noted that for the ABS control logic, the earlier the t3 stage is executed, the earlier the wheels are controlled, and the faster the system can execute the next cycle of control. Figure 5 In (a), (b), and (c), the motor unloading rate is relatively fast, and the t1 time can be shortened through effective strategy processing. The t2 time is determined by the inherent characteristics of the wheel dynamics (moment of inertia, force, mode, etc.). Therefore, the method of the present invention can make the ABS enter the t3 stage earlier to improve the control effect.

[0080] In addition, in order to more easily implement the control strategy of the present invention or improve the robustness of the control, the increase rate or the maximum value of the motor regenerative braking torque can be limited in step S11 to reduce the takeover state when the ABS function intervenes, and then the ABS control is performed based on the reduced takeover state, which can omit part of the control, for example, avoiding the occurrence of Figure 5 In this case, (a), (b), and (c) all need to be processed.

[0081] Figure 6 is a schematic diagram of the torque application effect of an embodiment of the present invention, Figure 6 (a) is an example of the control effect of applying the method of the present invention. Figure 6 (b) is an example of the control effect of the traditional hydraulic brake assist (Brake Assist, BA) function solution.

[0082] Specifically, the time scale represents the time when the vehicle braking system processes and controls at different stages. t0 represents the time when the driver starts to actuate the brake pedal, t1 represents the time when the input braking request meets the emergency braking judgment condition, and at t1 the electro-hydraulic composite brake assist function is activated and enters the state of processing and controlling vehicle braking. Figure 6 In (a), after the "electro-hydraulic composite brake assist function" controls the wheel brake, the ABS working conditions are met at time t2; see Figure 6 In (b), after the system hydraulic BA function controls the wheel braking, the ABS working conditions are met at time t3. When the ABS working conditions are met, the inherent characteristics of the wheel and the road surface state are the same. Assuming that the resistance, mass and other parameters have not changed, it can be deduced that the caliper braking torque T1 + regenerative braking torque T2 at time t2 is equal to the caliper braking torque T0 at time t3. Therefore, the vehicle has a significantly shorter braking coordination time under the control of the "electro-hydraulic composite braking assist function", that is, TTL_1 = t2-t0 is less than TTL_2 = t3-t0, (TTL_1 is the braking coordination time of the method of the present invention, and TTL_2 is the braking coordination time of the traditional hydraulic BA method), which means that compared with the traditional technology, the present invention enables the system to stabilize the vehicle speed to a safe level faster and has better anti-skid performance.

[0083] Figure 7 4 is a structural block diagram of a controller according to an embodiment of the present invention.

[0084] like Figure 7 As shown, the controller 500 includes: a processor 501 and a memory 503. The processor 501 and the memory 503 are connected, such as through a bus 502. Optionally, the controller 500 may also include a transceiver 504. It should be noted that in actual applications, the transceiver 504 is not limited to one, and the structure of the controller 500 does not constitute a limitation on the embodiments of the present invention.

[0085] Processor 501 may be a CPU (Central Processing Unit), a general purpose processor, a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. It may implement or execute various exemplary logic blocks, modules and circuits described in conjunction with the disclosure of the present invention. Processor 501 may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, etc.

[0086] The bus 502 may include a path to transmit information between the above components. The bus 502 may be a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus. The bus 502 may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 7 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0087] The memory 503 is used to store a computer program corresponding to the vehicle braking control method of the above embodiment of the present invention, and the computer program is controlled and executed by the processor 501. The processor 501 is used to execute the computer program stored in the memory 503 to implement the contents shown in the above method embodiment.

[0088] Among them, the controller 500 includes but is not limited to: mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (personal digital assistants), PADs (tablet computers), PMPs (portable multimedia players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 7 The controller 500 shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0089] The present invention also provides a vehicle.

[0090] Figure 8 4 is a structural block diagram of a vehicle according to an embodiment of the present invention.

[0091] like Figure 8As shown, a vehicle 800 includes the controller 500 of the above-described embodiment.

[0092] According to the vehicle braking control method, controller and vehicle proposed in the embodiment of the present invention, by judging the emergency braking state, in the stage of establishing the braking strength, the motor and the brake caliper are controlled to increase the braking force according to the maximum torque increase rate allowed by the system until the ABS function is triggered; when the ABS is activated, the feedback and the state level of the caliper are adjusted in a targeted manner, so that the brake caliper anti-lock control can enter the circulation mode normally. In this way, not only can the coordination time of the vehicle during emergency braking be reduced, the vehicle braking distance during emergency braking is shortened, and the braking performance of the vehicle is improved, but also the two torques of regenerative braking and caliper braking can be effectively connected, and the working range of regenerative braking can be further improved without adversely affecting the anti-lock control, and the time for the wheel to return to steady state is shortened, so that the ABS function can recognize the road surface more quickly and adjust the control mode more timely, which can better meet the upper-level control requirements of ADAS.

[0093] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection portion with one or more wirings (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0094] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0095] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" 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 representation of the above terms does 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.

[0096] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0097] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0098] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0099] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0100] 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: The method comprises: In response to an emergency braking request of the vehicle, a brake caliper of the vehicle is controlled to increase a caliper braking torque according to a first rate threshold, and a motor of the vehicle is controlled to increase a regenerative braking torque according to a second rate threshold to brake the wheels of the vehicle.

2. The vehicle braking control method according to claim 1, characterized in that: Before controlling the brake caliper of the vehicle to increase the caliper braking torque according to the first rate threshold and controlling the motor of the vehicle to increase the regenerative braking torque according to the second rate threshold, the method further includes: It is determined that a vehicle speed of the vehicle is greater than a first speed threshold.

3. The vehicle braking control method according to claim 1 or 2, characterized in that: After controlling the brake caliper of the vehicle to increase the caliper braking torque according to the first rate threshold, and controlling the motor of the vehicle to increase the regenerative braking torque according to the second rate threshold, the method further includes: responsive to activation of an anti-lock braking system of the vehicle, adjusting wheel braking force; When the wheel speed of the vehicle converges to the vehicle speed and the regenerative braking torque is less than or equal to a braking torque threshold, anti-lock control is performed by the brake caliper.

4. The vehicle braking control method according to claim 3, characterized in that: Adjust the wheel braking force as follows: maintaining the caliper braking torque unchanged, and controlling the motor to reduce the regenerative braking torque to the braking torque threshold according to a third rate threshold, wherein the third rate threshold is greater than the second rate threshold; or, controlling the brake caliper to continue to increase the caliper braking torque according to the first rate threshold, and controlling the motor to reduce the regenerative braking torque to the braking torque threshold according to a fourth rate threshold, wherein the fourth rate threshold is less than the third rate threshold; or, The brake caliper is controlled to reduce the caliper braking torque to a target caliper braking torque, and the motor is controlled to reduce the regenerative braking torque to the braking torque threshold according to the third rate threshold.

5. The vehicle braking control method according to claim 4, characterized in that: The fourth rate threshold is determined according to the regenerative braking torque, the first rate threshold, the target caliper braking torque, and the caliper braking torque.

6. The vehicle braking control method according to claim 2, characterized in that: The emergency braking request includes: a driver emergency braking request and / or an auxiliary driving system emergency braking request.

7. The vehicle braking control method according to claim 6, characterized in that: If the vehicle's brake pedal travel is greater than or equal to a first travel threshold and the rate of increase of the brake pedal travel is greater than or equal to a first rate, the rate of increase of the brake pedal travel is greater than or equal to a second rate, or the brake pedal travel is greater than or equal to a second travel threshold and the brake pedal pressure is greater than a first pressure threshold, it is determined that the driver's emergency braking request is obtained, wherein the second rate is greater than the first rate.

8. The vehicle braking control method according to claim 6, characterized in that: If the vehicle deceleration requested by the assisted driving system is greater than the first deceleration threshold or the assisted driving system enters an emergency braking state in response to an emergency braking command, it is determined that the assisted driving system emergency braking request is obtained.

9. The vehicle braking control method according to claim 1, characterized in that: The first rate threshold is determined according to the idle travel between the caliper friction pad of the brake caliper and the brake disc of the vehicle, the rate of change of the force applied by the brake caliper between the caliper friction pad and the brake disc, and the friction coefficient between the caliper friction pad and the brake disc; The second rate threshold is determined according to the torque loading rate of the motor and the maximum power that the energy recovery system of the vehicle can withstand.

10. The vehicle braking control method according to claim 2, characterized in that: The method further comprises: If the emergency braking request is obtained and the vehicle speed is greater than the first speed threshold, the vehicle is controlled to activate the electro-hydraulic composite brake assist function: If the vehicle speed is less than or equal to the minimum control speed of the anti-lock braking system, the judgment condition of the emergency braking request is no longer met, or the brake pedal information of the vehicle meets the conditions for triggering the anti-lock braking system, the vehicle is controlled to exit the electro-hydraulic composite brake assist function, wherein the minimum control speed is less than the first speed threshold.

11. The vehicle braking control method according to claim 10, characterized in that: If the brake pedal travel decreases by the third travel threshold, or the brake pedal pressure decreases by the second pressure threshold, it is determined that the determination condition for the emergency braking request is no longer satisfied.

12. A controller comprising a memory, a processor and a computer program stored in the memory, characterized in that: When the computer program is executed by the processor, the vehicle braking control method according to any one of claims 1 to 11 is implemented.

13. A vehicle, characterized in that: Comprising a controller as claimed in claim 12.

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