Zero positioning method, system and equipment for piston of brake system and medium

Abstract

The invention relates to a brake system piston zero positioning method, system and device and a medium. The method comprises the steps that the real-time motor corner position and the real-time motor rotating speed are obtained, and the displacement of a piston is determined according to the real-time motor corner position; a brake signal is received, a motor is controlled to operate in a rotating speed control mode, and a piston is driven to return to a mechanical zero point; judging whether the real-time rotating speed of the motor is lower than a first preset rotating speed threshold value and continuously reaches a first preset time threshold value, if so, switching the motor from a rotating speed control mode to a torque control mode, operating at a target torque, and recording a first rotating angle position of the motor; and in the torque control mode, whether the piston really reaches the mechanical zero point or not is judged according to the real-time change of the rotating speed of the motor or the real-time change of the rotating angle position of the motor, and a corresponding control strategy is executed according to a judgment result until it is confirmed that the piston is stably located at the mechanical zero point. According to the method, the piston zero positioning robustness and precision can be improved, and the stability and safety of a brake system are guaranteed.

Description

Technical Field

[0001] This invention relates to the field of braking technology, and in particular to a method, system, device and medium for zero-position positioning of a piston in a braking system. Background Technology

[0002] The hydraulic brake-by-wire system includes a hydraulic oil supply system, brake pedal-related devices, an electronic control unit (ECU), and a hydraulic actuator. The hydraulic actuator consists of a booster unit (motor and booster cylinder), a wheel cylinder, and corresponding hydraulic circuits. The ECU sends control commands such as speed and torque to the motor to control the speed and displacement of the piston in the booster cylinder. The motor, through forward / reverse rotation and a transmission mechanism including planetary gears and ball screws, pushes the piston in the booster cylinder forward / backward to achieve pressure increase / depression in the braking system. The piston displacement is calculated by a motor angle sensor based on the transmission ratio. After the system is powered on, the motor reverses to push the piston back to one end of the booster cylinder against the wall. This position is defined as zero degrees, serving as the piston zero-point position. After confirming the piston zero-point position, the system uses this position as the piston reference zero point for forward / backward piston control, allowing the system to enter the pressure-building state.

[0003] The piston zero-point position is typically confirmed by sending a speed command to the motor and then using the feedback of the actual speed and torque from the motor to determine whether the piston has retracted to the dead zone near the piston wall. However, in mass-produced vehicles, uncertainties such as increased oil viscosity in cold environments, slight jamming between the motor and turbocharger transmission mechanism, and motor speed fluctuations caused by elastic deformation of the transmission mechanism can lead to occasional issues with the piston failing to zero, taking too long to reach the zero point, or experiencing continuous impacts and rebounds against the wall. Inaccurate piston zero-point position can cause the piston to impact the wall during the forward pressure build-up process, damaging mechanical components and significantly affecting vehicle braking safety. Summary of the Invention

[0004] The present invention provides a method, system, device and medium for piston zero-position positioning in a braking system, in order to overcome at least one of the above-mentioned technical problems existing in the prior art.

[0005] To achieve the above objectives, the embodiments of the present invention adopt the following technical solutions: In a first aspect, the present invention provides a method for zero-position positioning of a piston in a braking system, comprising: The real-time motor rotation angle position and real-time motor speed are obtained, and the piston displacement is determined based on the real-time motor rotation angle position. Receive the braking signal, control the motor to operate in speed control mode, and drive the piston to retract to the mechanical zero point; Determine whether the real-time motor speed is lower than the first preset speed threshold and continues to reach the first preset time threshold. If so, switch the motor from the speed control mode to the torque control mode to run at the target torque, and record the first motor rotation angle position. In the torque control mode, based on the change in the real-time motor speed or the change in the real-time motor angle position, it is determined whether the piston has actually reached the mechanical zero point, and the corresponding control strategy is executed according to the determination result until it is confirmed that the piston is stably at the mechanical zero point.

[0006] In one possible implementation of the first aspect, determining whether the piston has actually reached the mechanical zero point based on the change in the real-time motor speed, and executing a corresponding control strategy based on the determination result, includes: If the real-time motor speed recovers from a state below the first preset speed threshold to the second preset speed threshold under the action of the target torque, it is determined that the piston has not reached the mechanical zero point, wherein the second preset speed threshold is greater than the first preset speed threshold; Switch the torque control mode to the speed control mode.

[0007] In one possible implementation of the first aspect, the step of determining whether the piston has actually reached the mechanical zero point based on the change in the real-time motor rotation angle, and executing a corresponding control strategy based on the determination result, includes: If the real-time motor speed does not recover to the second preset speed threshold under the action of the target torque, then it is determined whether the real-time motor speed recovers to the first preset speed threshold or whether the difference between the real-time motor angle position and the first motor angle position exceeds the first preset angle position change value. If so, it is determined that the piston has contacted the mechanical zero point, the rotation angle position of the second motor is recorded, and the torque is unloaded.

[0008] In one possible implementation of the first aspect, the torque-unloaded state includes: The motor is switched from the target torque to a limiting torque, wherein the limiting torque is less than the target torque; Determine whether the difference between the real-time motor rotation angle position and the second motor rotation angle position is less than the second preset rotation angle position change value; If so, then the piston is determined to be stably at the mechanical zero point.

[0009] In one possible implementation of the first aspect, if the difference between the real-time motor rotation angle position and the second motor rotation angle position is greater than the second preset rotation angle position change value, the method further includes: Stop unloading torque and increase the motor torque from the current torque to the target torque; Maintain the target torque operation until the second preset time threshold, and determine that the piston is stably at the mechanical zero point.

[0010] In one possible implementation of the first aspect, after receiving the braking signal, the method further includes: The real-time brake fluid temperature is obtained, and the limiting torque in the speed control mode and the target torque in the torque control mode are adjusted according to the real-time brake fluid temperature.

[0011] In one possible implementation of the first aspect, after confirming that the piston is stably at the mechanical zero point, the method further includes: Record the rotation angle position of the third motor, and use the rotation angle position of the third motor as the zero-point reference position for subsequent control.

[0012] Compared with the prior art, the present invention has at least the following beneficial effects: The present invention provides a piston zero-position positioning method for a braking system. By monitoring signals such as motor rotation angle position, motor speed and torque, the method controls the speed and torque of the motor, which can improve the robustness and accuracy of piston zero-position positioning and ensure the stability and safety of the braking system.

[0013] In a second aspect, the present invention provides a piston zero-position positioning system for a braking system, comprising: The piston displacement monitoring module is used to acquire the real-time motor rotation angle position and the real-time motor speed, and to determine the piston displacement based on the real-time motor rotation angle position. The braking signal acquisition module is used to receive braking signals, control the motor to operate in speed control mode, and drive the piston to retract to the mechanical zero point; The motor control mode switching module is used to determine whether the real-time motor speed is lower than the first preset speed threshold and continues to reach the first preset time threshold. If so, the motor is switched from the speed control mode to the torque control mode to run at the target torque, and the first motor rotation angle position is recorded. The mechanical zero-point identification module is used to determine whether the piston has actually reached the mechanical zero point based on the change in the real-time motor speed or the change in the real-time motor angle position in the torque control mode, and to execute the corresponding control strategy according to the determination result until it is confirmed that the piston is stably at the mechanical zero point.

[0014] Thirdly, the present invention provides an electronic device comprising: at least one processor and at least one memory, wherein the memory stores computer-readable instructions; the computer-readable instructions are executed by one or more of the processors to cause the electronic device to implement the braking system piston zero-position positioning method as in any implementation of the first aspect.

[0015] Fourthly, the present invention provides a storage medium having a computer-executable program stored thereon, the computer-executable program being used to cause a computer to execute the braking system piston zero-position positioning method as in any implementation of the first aspect.

[0016] Understandably, the beneficial effects achieved by the system of the second aspect, the electronic device of the third aspect, and the storage medium of the fourth aspect provided above can be referred to in light of the beneficial effects of the first aspect and any of its possible design embodiments, which will not be repeated here. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention; Figure 2 A flowchart of a method for zero-position positioning of a piston in a braking system provided in an embodiment of the present invention; Figure 3 This is a structural block diagram of a piston zero-position positioning system for a braking system provided in an embodiment of the present invention. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be described below with reference to the accompanying drawings. In the description of the present invention, unless otherwise stated, " / " indicates that the objects before and after are in an "or" relationship. For example, A / B can represent A or B. The "or" in the present invention is merely a description of the relationship between the related objects, indicating that three relationships can exist. For example, A or B can represent: A alone, A and B simultaneously, and B alone. A and B can be singular or plural. Furthermore, in the description of the present invention, unless otherwise stated, "multiple" refers to two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items.

[0020] Furthermore, to facilitate a clear description of the technical solutions of the embodiments of the present invention, the terms "first" and "second" are used in the embodiments of the present invention to distinguish identical or similar items with essentially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and the terms "first" and "second" are not necessarily different.

[0021] In this embodiment of the invention, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design described as "exemplary" or "for example" in this embodiment of the invention should not be construed as superior or more advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner for ease of understanding.

[0022] The hydraulic brake-by-wire system includes a hydraulic oil supply system, brake pedal-related devices, an electronic control unit (ECU), and a hydraulic actuator. The hydraulic actuator consists of a booster unit (motor and booster cylinder), a wheel cylinder, and corresponding hydraulic circuits. The ECU sends control commands such as speed and torque to the motor to control the speed and displacement of the piston in the booster cylinder. The motor, through forward / reverse rotation and a transmission mechanism including planetary gears and ball screws, pushes the piston in the booster cylinder forward / backward to achieve pressure increase / depression in the braking system. The piston displacement is calculated by a motor angle sensor based on the transmission ratio. After the system is powered on, the motor reverses to push the piston back to one end of the booster cylinder against the wall. This position is defined as zero degrees, serving as the piston zero-point position. After confirming the piston zero-point position, the system uses this position as the piston reference zero point for forward / backward piston control, allowing the system to enter the pressure-building state.

[0023] The piston zero-point position is typically confirmed by sending a speed command to the motor and then using the feedback of the actual speed and torque from the motor to determine whether the piston has retracted to the dead zone near the piston wall. However, in mass-produced vehicles, uncertainties such as increased oil viscosity in cold environments, slight jamming between the motor and turbocharger transmission mechanism, and motor speed fluctuations caused by elastic deformation of the transmission mechanism can lead to occasional issues with the piston failing to zero, taking too long to reach the zero point, or experiencing continuous impacts and rebounds against the wall. Inaccurate piston zero-point position can cause the piston to impact the wall during the forward pressure build-up process, damaging mechanical components and significantly affecting vehicle braking safety.

[0024] In view of this, on the one hand, embodiments of the present invention provide a piston zero-position positioning method for a braking system, comprising: acquiring real-time motor rotation angle position and real-time motor speed, and determining the piston displacement based on the real-time motor rotation angle position; receiving a braking signal, controlling the motor to operate in a speed control mode, and driving the piston to retract towards the mechanical zero point; determining whether the real-time motor speed is lower than a first preset speed threshold and continues to reach a first preset time threshold, and if so, switching the motor from the speed control mode to a torque control mode to operate at a target torque, and recording the first motor rotation angle position; in the torque control mode, determining whether the piston has actually reached the mechanical zero point based on the change in the real-time motor speed or the change in the real-time motor rotation angle position, and executing a corresponding control strategy based on the determination result, until it is confirmed that the piston is stably located at the mechanical zero point.

[0025] The piston zero-position positioning method for a braking system provided in this embodiment of the invention improves the robustness and accuracy of piston zero-position positioning by monitoring signals such as motor rotation angle, motor speed and torque, and controlling the speed and torque of the motor, thereby ensuring the stability and safety of the braking system.

[0026] In some embodiments, the piston zero-position positioning method of the braking system provided by the present invention can be executed by any electronic device 20 with data processing capabilities, such as a general-purpose computer, personal computer, laptop computer, switch or tablet computer, etc. The specific implementation of the electronic device 20 is not limited here.

[0027] Figure 1 A schematic diagram of the hardware structure of an electronic device provided in an embodiment of the present invention is shown. The electronic device 20 includes a processor 210, a memory 220, and a communication interface 230.

[0028] Processor 210 may include one or more processing cores. Processor 210 connects to various parts within electronic device 200 using various interfaces and lines, and performs various functions and processes data of electronic device 200 by running or executing instructions, programs, code sets, or instruction sets stored in memory 220, and by calling data stored in memory 220. Optionally, processor 210 may be implemented using at least one of the following hardware forms: Central Processing Unit (CPU), Graphics Processing Unit (GPU), Digital Signal Processing (DSP), Field-Programmable Gate Array (FPGA), and Programmable Logic Array (PLA).

[0029] The memory 220 may include random access memory (RAM) or read-only memory (ROM). Optionally, the memory 220 may include a non-transitory computer-readable storage medium. The memory 220 may be used to store instructions, programs, code, code sets, or instruction sets. The memory 220 may include a program storage area. This program storage area may store instructions for implementing an operating system, instructions for implementing at least one function, instructions for implementing the various method embodiments described above, etc.

[0030] Communication interface 230 is used to communicate with other devices, equipment or communication networks, such as data storage devices, image processing devices or Ethernet, wireless access network (RAN), wireless local area network (WLAN), etc.

[0031] In terms of physical implementation, the aforementioned devices (such as processor 210, memory 220, and communication interface 230) can each be devices within the same device (such as a laptop computer). Alternatively, at least two of these devices can be located within the same device, i.e., as different devices within the same device, similar to the deployment of devices or components in a distributed system.

[0032] It is understood that the structure illustrated in this embodiment does not constitute a specific limitation on the electronic device 20. In other embodiments of the present invention, the electronic device 20 may include more or fewer components than illustrated, or combine some components, or split some components, or have different component arrangements. The illustrated components may be implemented in hardware, software, or a combination of software and hardware.

[0033] The following description, in conjunction with the accompanying drawings, illustrates a method for zero-position positioning of a braking system piston provided by an embodiment of the present invention.

[0034] like Figure 2 As shown, this embodiment of the invention provides a method for zero-position positioning of a braking system piston, which may include, but is not limited to: S1: Obtain the real-time motor rotation angle position and real-time motor speed, and determine the piston displacement based on the real-time motor rotation angle position.

[0035] In specific implementation, the braking system in this embodiment of the invention can be a hydraulic brake-by-wire system. The motor in this system is connected to the piston of the plunger pump via a planetary gear reduction mechanism and a ball screw. Therefore, the piston displacement can be calculated using the following formula: ; in, This indicates the displacement of the piston in a plunger pump, in mm. Indicates the lead of the ball screw, in mm / rad; Indicates the transmission ratio of the planetary gear reduction mechanism; Indicates the motor's rotation angle position, in rad.

[0036] It should be noted that the embodiments of the present invention may also use other methods to connect the motor and the plunger pump piston, which are not limited here.

[0037] S2: Receives a braking signal, controls the motor to operate in speed control mode, and drives the piston to retract to the mechanical zero point.

[0038] In one feasible implementation, after receiving the braking signal, the embodiments of the present invention may, but are not limited to, further include: The real-time brake fluid temperature is obtained, and the limiting torque in the speed control mode and the target torque in the torque control mode are adjusted according to the real-time brake fluid temperature.

[0039] The embodiments of the present invention dynamically adjust the limiting torque in the speed control mode and the target torque in the torque control mode according to the temperature of the brake fluid. This can effectively avoid the problem of inaccurate piston zero-positioning caused by dynamic friction due to increased viscosity of the brake fluid in low-temperature environments, and improve the stability of the braking system.

[0040] S3: Determine whether the real-time motor speed is lower than the first preset speed threshold and continues to reach the first preset time threshold. If so, switch the motor from the speed control mode to the torque control mode to run at the target torque, and record the first motor rotation angle position.

[0041] In the specific implementation process, the motor of the braking system drives the piston to retract synchronously at a certain target speed in speed control mode. When the piston approaches the mechanical zero point, the motor speed will gradually decrease due to the contact between the piston and the limiting component at the mechanical zero point. Therefore, when the real-time motor speed decreases to the first preset speed threshold and continues to reach the first preset time threshold, it is considered that the piston has approached the mechanical zero point. Then, the motor is switched from the speed control mode to the torque control mode to operate at the target torque.

[0042] S4: In the torque control mode, based on the change in the real-time motor speed or the change in the real-time motor angle position, determine whether the piston has actually reached the mechanical zero point, and execute the corresponding control strategy according to the determination result until it is confirmed that the piston is stably at the mechanical zero point.

[0043] In one feasible implementation, the step of determining whether the piston has actually reached the mechanical zero point based on the change in the real-time motor rotation angle, and executing the corresponding control strategy based on the determination result, may include, but is not limited to: If the real-time motor speed recovers from a state below the first preset speed threshold to the second preset speed threshold under the action of the target torque, it is determined that the piston has not reached the mechanical zero point, wherein the second preset speed threshold is greater than the first preset speed threshold; Switch the torque control mode to the speed control mode.

[0044] In the specific implementation process, when the real-time motor speed recovers from a state below the first preset speed threshold to the second preset speed threshold under the action of the target torque, it indicates that the reason for the decrease in motor speed may be due to dynamic friction resistance such as jamming of the transmission mechanism, and the piston has not actually reached the mechanical zero point. At this time, the torque control mode is switched to the speed control mode, so that the motor runs in the speed control mode, and the real-time motor speed is re-evaluated to see if it is below the first preset speed threshold and continues to reach the first preset time threshold.

[0045] In one feasible implementation, the step of determining whether the piston has actually reached the mechanical zero point based on the change in the real-time motor rotation angle, and executing the corresponding control strategy based on the determination result, may include, but is not limited to: If the real-time motor speed does not recover to the second preset speed threshold under the action of the target torque, then it is determined whether the real-time motor speed recovers to the first preset speed threshold or whether the difference between the real-time motor angle position and the first motor angle position exceeds the first preset angle position change value. If so, it is determined that the piston has contacted the mechanical zero point, the rotation angle position of the second motor is recorded, and the torque is unloaded.

[0046] In one feasible implementation, the torque-unloading state in the embodiments of the present invention may include, but is not limited to: The motor is switched from the target torque to a limiting torque, wherein the limiting torque is less than the target torque; Determine whether the difference between the real-time motor rotation angle position and the second motor rotation angle position is less than the second preset rotation angle position change value; If so, then the piston is determined to be stably at the mechanical zero point.

[0047] In the specific implementation process, the embodiments of the present invention use a gradient reduction method to switch the motor from the target torque to the limit torque. After the motor switches from the target torque to the limit torque, the motor operates in the speed control mode.

[0048] In the specific implementation process, during the transition of the motor from the target torque to the limiting torque, it is determined whether the difference between the real-time motor rotation angle position and the second motor rotation angle position is less than the second preset rotation angle position change value. If so, it is determined that the piston is stably at the mechanical zero point. If not, it indicates that the motor-piston transmission mechanism has rebounded as the torque decreases. In this case, the embodiments of the present invention may, but are not limited to, also include: Stop unloading torque and increase the motor torque from the current torque to the target torque; Maintain the target torque operation until the second preset time threshold, and determine that the piston is stably at the mechanical zero point.

[0049] The embodiments of the present invention, by judging the changes in the real-time motor rotation position during the torque unloading process and adjusting the control strategy accordingly, can effectively avoid elastic deformation caused by factors such as material characteristics of the motor-piston transmission system or errors in processing and assembly processes, thereby improving the robustness and accuracy of piston zero-position positioning.

[0050] In one feasible implementation, after confirming that the piston is stably at the mechanical zero point, the embodiments of the present invention may, but are not limited to, further include: Record the rotation angle position of the third motor, and use the rotation angle position of the third motor as the zero-point reference position for subsequent control.

[0051] In the specific implementation process, after the third motor rotation position is recorded in the embodiments of the present invention, the difference between the obtained real-time motor rotation position and the third motor rotation position can be used as the control signal of the braking system for subsequent pressure build-up control, pressure regulation and system monitoring and diagnosis, etc., which is not limited here.

[0052] The piston zero-position positioning method for the braking system provided in this embodiment of the invention improves the robustness and accuracy of piston zero-position positioning by monitoring signals such as motor rotation angle, motor speed and torque, and controlling the speed and torque of the motor, thereby ensuring the stability and safety of the braking system.

[0053] Based on the braking system piston zero-position positioning method provided in the first aspect, embodiments of the present invention provide a braking system piston zero-position positioning system, such as... Figure 3 As shown, the braking system piston zero-position positioning system includes: The piston displacement monitoring module 110 is used to acquire the real-time motor rotation angle position and the real-time motor speed, and determine the piston displacement based on the real-time motor rotation angle position. The braking signal acquisition module 120 is used to receive braking signals, control the motor to operate in speed control mode, and drive the piston to retract to the mechanical zero point. The motor control mode switching module 130 is used to determine whether the real-time motor speed is lower than the first preset speed threshold and continues to reach the first preset time threshold. If so, the motor is switched from the speed control mode to the torque control mode to run at the target torque, and the first motor rotation angle position is recorded. The mechanical zero-point identification module 140 is used to determine whether the piston has actually reached the mechanical zero point based on the change in the real-time motor speed or the change in the real-time motor angle position in the torque control mode, and to execute the corresponding control strategy according to the determination result until it is confirmed that the piston is stably at the mechanical zero point.

[0054] Based on the braking system piston zero-position positioning method provided in the first aspect, this embodiment of the invention also provides a storage medium storing a computer-executable program. The computer-executable program is used to cause a computer to execute the braking system piston zero-position positioning method as described in any implementation of the first aspect. Explanations of the relevant content and descriptions of the beneficial effects of any of the computer-readable storage media provided above can be found in the corresponding embodiments described above, and will not be repeated here.

[0055] Those skilled in the art will understand that the program for implementing all or part of the steps of the above embodiments, which can be executed by a program instructing related hardware, can be stored in a computer-readable storage medium. The storage medium mentioned above can be a read-only memory, a random access memory, etc. The processing unit or processor mentioned above can be a central processing unit, a general-purpose processor, an application-specific integrated circuit (ASIC), a microprocessor (DSP), a field-programmable gate array (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof.

[0056] This invention also provides a computer program product containing instructions that, when executed on a computer, cause the computer to perform any of the methods described in the above embodiments. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the flow or function according to the embodiments of this invention is generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, computer instructions can be transmitted from one website, computer, server, or data center to another via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium accessible to a computer or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., SSD), etc.

[0057] It should be noted that the devices for storing computer instructions or computer programs provided in the embodiments of the present invention, such as, but not limited to, the aforementioned memory, computer-readable storage medium, and communication chip, are all non-transitory. Those skilled in the art should recognize that the functions described in the embodiments of the present invention in one or more of the above examples can be implemented using hardware, software, firmware, or any combination thereof. When implemented using software, these functions can be stored in a computer-readable storage medium or transmitted as one or more instructions or code on a computer-readable storage medium. Computer-readable storage media include computer storage media and communication media, wherein communication media include any medium that facilitates the transmission of computer programs from one place to another. Storage media can be any available medium accessible to general-purpose or special-purpose computers.

[0058] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for piston zero-position positioning in a braking system, characterized in that, include: The real-time motor rotation angle position and real-time motor speed are obtained, and the piston displacement is determined based on the real-time motor rotation angle position. Receive the braking signal, control the motor to operate in speed control mode, and drive the piston to retract to the mechanical zero point; Determine whether the real-time motor speed is lower than the first preset speed threshold and continues to reach the first preset time threshold. If so, switch the motor from the speed control mode to the torque control mode to run at the target torque, and record the first motor rotation angle position. In the torque control mode, based on the change in the real-time motor speed or the change in the real-time motor angle position, it is determined whether the piston has actually reached the mechanical zero point, and the corresponding control strategy is executed according to the determination result until it is confirmed that the piston is stably at the mechanical zero point.

2. The method for zero-position positioning of a braking system piston according to claim 1, characterized in that, The step of determining whether the piston has actually reached the mechanical zero point based on the real-time change in motor speed, and executing the corresponding control strategy based on the determination result, includes: If the real-time motor speed recovers from a state below the first preset speed threshold to the second preset speed threshold under the action of the target torque, it is determined that the piston has not reached the mechanical zero point, wherein the second preset speed threshold is greater than the first preset speed threshold; Switch the torque control mode to the speed control mode.

3. The method for piston zero-position positioning in a braking system according to claim 1, characterized in that, The step of determining whether the piston has actually reached the mechanical zero point based on the real-time change in the motor's rotation angle, and executing the corresponding control strategy based on the determination result, includes: If the real-time motor speed does not recover to the second preset speed threshold under the action of the target torque, then it is determined whether the real-time motor speed recovers to the first preset speed threshold or whether the difference between the real-time motor angle position and the first motor angle position exceeds the first preset angle position change value. If so, it is determined that the piston has contacted the mechanical zero point, the rotation angle position of the second motor is recorded, and the torque is unloaded.

4. The method for zero-position positioning of a braking system piston according to claim 3, characterized in that, The unloaded torque state includes: The motor is switched from the target torque to a limiting torque, wherein the limiting torque is less than the target torque; Determine whether the difference between the real-time motor rotation angle position and the second motor rotation angle position is less than the second preset rotation angle position change value; If so, then the piston is determined to be stably at the mechanical zero point.

5. A method for piston zero-position positioning in a braking system according to claim 4, characterized in that, If the difference between the real-time motor rotation angle position and the second motor rotation angle position is greater than the second preset rotation angle position change value, the method further includes: Stop unloading torque and increase the motor torque from the current torque to the target torque; Maintain the target torque operation until the second preset time threshold, and determine that the piston is stably at the mechanical zero point.

6. The method for piston zero-position positioning in a braking system according to claim 1, characterized in that, After receiving the braking signal, the method further includes: The real-time brake fluid temperature is obtained, and the limiting torque in the speed control mode and the target torque in the torque control mode are adjusted according to the real-time brake fluid temperature.

7. The method for zero-position positioning of a braking system piston according to claim 1, characterized in that, After confirming that the piston is stably at the mechanical zero point, the process further includes: Record the rotation angle position of the third motor, and use the rotation angle position of the third motor as the zero-point reference position for subsequent control.

8. A piston zero-position positioning system for a braking system, characterized in that, include: The piston displacement monitoring module is used to acquire the real-time motor rotation angle position and the real-time motor speed, and to determine the piston displacement based on the real-time motor rotation angle position. The braking signal acquisition module is used to receive braking signals, control the motor to operate in speed control mode, and drive the piston to retract to the mechanical zero point; The motor control mode switching module is used to determine whether the real-time motor speed is lower than the first preset speed threshold and continues to reach the first preset time threshold. If so, the motor is switched from the speed control mode to the torque control mode to run at the target torque, and the first motor rotation angle position is recorded. The mechanical zero-point identification module is used to determine whether the piston has actually reached the mechanical zero point based on the change in the real-time motor speed or the change in the real-time motor angle position in the torque control mode, and to execute the corresponding control strategy according to the determination result until it is confirmed that the piston is stably at the mechanical zero point.

9. An electronic device, characterized in that, include: A memory, one or more processors; the memory is coupled to the processors; wherein the memory stores computer program code, the computer program code including computer instructions, which, when executed by the processor, cause the electronic device to perform the braking system piston zero-position positioning method as described in any one of claims 1 to 7.

10. A storage medium storing a computer-executable program, characterized in that, The computer-executable program is used to cause the computer to perform the braking system piston zero-position positioning method as described in any one of claims 1 to 7.

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