Vehicle control method, vehicle and computer readable storage medium

Abstract

The invention relates to a vehicle control method, a vehicle and a computer readable storage medium, and the method comprises the steps that first parameters and second parameters of a motor are obtained, the first parameters comprise the current value of the motor and the change rate of the current value, and the second parameters comprise the rotation angle value of the motor and the change rate of the rotation angle value; determining a first time period based on the first parameter; determining a second time period based on the second parameter; obtaining a verification value based on the first time period and the second time period; obtaining a clearance value between a friction plate and a brake disc in the brake based on the verification value and the rotation angle value of the motor in the first time period or the second time period; and outputting a corresponding checking signal to the brake based on the gap value. The problem that an existing scheme is insufficient in gap precision and poor in feasibility can be solved.

Description

Technical Field

[0001] The present application relates to the technical field of brake control, and in particular to a vehicle control method, a vehicle, and a computer-readable storage medium. Background Art

[0002] In a brake-by-wire system that eliminates pressure sensors, algorithms can accurately calculate brake clamping force to decelerate and park the vehicle. However, continued wear of the friction pads increases the gap between them and the brake disc, directly affecting the accuracy of the clamping force algorithm. Therefore, real-time sensing of disc gap changes is a core challenge in the implementation of sensorless brake-by-wire technology.

[0003] Current solutions mainly include: establishing a static compensation mechanism based on bench or actual vehicle test data, and implanting an algorithm to correct the clamping force calculation; dynamically introducing a wear variation coefficient in the clamping force model and adjusting the calculation through preset parameters; integrating a wear sensor inside the brake to directly monitor the friction plate thickness or piston position.

[0004] However, in the above scheme, due to the differences in vehicle models and working conditions, the test data compensation and model correction lack wide applicability, cannot guarantee the control accuracy of the brake throughout its life cycle, and are difficult to meet the high-safety level braking requirements; although the built-in sensor can output the disc gap with higher precision, it needs to occupy the internal space of the brake, which easily leads to an increase in the axial size of the assembly, affecting the compactness of the vehicle layout and facing durability risks in high-temperature and oily environments, and has poor feasibility. Summary of the Invention

[0005] The embodiments of the present application provide a vehicle control method, a vehicle, and a computer-readable storage medium, aiming to improve the problems of insufficient gap accuracy and poor feasibility of existing solutions.

[0006] The present application first provides a vehicle control method, the vehicle includes a motor and a brake, the method includes: obtaining a first parameter and a second parameter of the motor, the first parameter includes the current value of the motor and the rate of change of the current value, and the second parameter includes the rotation angle value of the motor and the rate of change of the rotation angle value; determining a first time period based on the first parameter; determining a second time period based on the second parameter; obtaining a verification value based on the first time period and the second time period; obtaining a gap value between the friction plate and the brake disc in the brake based on the verification value and the rotation angle value of the motor in the first time period or the second time period; and outputting a corresponding calibration signal to the brake based on the gap value.

[0007] In the control method of the present application, the first time period is defined by obtaining the motor current and current change during the brake release process; at the same time, the second time period is defined by obtaining the motor's rotation angle change rate, and the verification value is generated using the difference between the two time periods. The gap value between the friction plate and the brake disc is accurately calculated in combination with the rotation angle value within the time period and the mechanical parameters of the brake. That is, a redundant verification mechanism of current and rotation angle dual signals is adopted, and the reliability of the gap calculation is improved through time period cross-validation, thereby improving the problems of insufficient gap accuracy and poor feasibility of the existing scheme.

[0008] In some embodiments, the method includes: in response to the vehicle being in a braking process or a braking release process, executing the step of obtaining the first parameter and the second parameter of the motor; wherein the vehicle being in a braking process includes receiving a brake pedal signal, a vehicle controller inputting a braking signal or a braking process signal, and the vehicle being in a braking release process includes receiving a brake pedal stroke reduction signal, a vehicle controller inputting a braking release signal or a braking release process signal.

[0009] In some embodiments, the method includes: in response to the vehicle having a braking process and a braking release process, and the braking process precedes the braking release process, executing the step of obtaining the first parameter and the second parameter of the motor; wherein the vehicle having a braking process includes receiving a brake pedal signal, a vehicle controller inputting a braking signal or a braking process signal, and the vehicle having a braking release process includes receiving a brake pedal stroke reduction signal, a vehicle controller inputting a braking release signal or a braking release process signal.

[0010] In some embodiments, determining the first time period based on the first parameter includes: determining the moment when the current value approaches or is equal to 0 as the first moment; determining the moment when the rate of change of the current value is the maximum value as the second moment; and determining the time period from the first moment to the second moment as the first time period.

[0011] In some embodiments, it also includes: determining the moment when the rate of change of the angle value is less than 0 or greater than 0 as the third moment; determining the moment when the rate of change of the angle value is equal to 0 as the fourth moment; and determining the period from the third moment to the fourth moment as the second period.

[0012] In some embodiments, the gap value between the friction plate and the brake disc in the brake is obtained based on the verification value and the rotation angle value of the motor in the first time period or the second time period, including: if the verification value is less than or equal to the preset calibration value, the gap value is calculated based on the conversion relationship between the rotation angle value at the first moment, the rotation angle value at the second moment and the brake configuration; or, if the verification value is less than or equal to the preset calibration value, the gap value is calculated based on the conversion relationship between the rotation angle value at the third moment, the rotation angle value at the fourth moment and the brake configuration; wherein the brake configuration includes the screw lead of the piston and the ratio of the screw angle to the displacement of the friction plate in the brake.

[0013] In some embodiments, obtaining the first parameter and the second parameter of the motor includes: obtaining current values at multiple moments, obtaining the rate of change of the current values based on the current values at multiple moments and the time difference between the multiple moments, and / or obtaining the angle values at multiple moments, obtaining the rate of change of the angle values based on the angle values at multiple moments and the time difference between the multiple moments.

[0014] In some embodiments, the method further includes: in response to receiving a parking signal, outputting a corresponding driving signal to the motor based on the gap value to control the vehicle to complete parking; or, outputting a corresponding safety redundancy signal to the brake based on the gap value.

[0015] The present application also provides a vehicle, including a wire-controlled brake, a gap calculation device and a zone controller, wherein the wire-controlled brake is used for motor braking; the gap calculation device is used to implement the method of any embodiment of the present application to calculate the gap value between the friction pad and the brake disc in the brake and send it to the zone controller; the zone controller is used to output a calibration signal to the wire-controlled brake based on the gap value.

[0016] In the vehicle of the present application, a gap output device is deployed, and the braking action is performed by the wire control brake. The regional controller receives the gap value and calibrates the clamping force model, thereby forming a closed-loop control. The real-time gap data is used to dynamically optimize the braking force output to solve the problem of clamping force attenuation caused by wear.

[0017] The present application also provides a computer-readable storage medium, in which a computer program is stored. When the computer program is executed by a processor, the method of any embodiment of the present application is implemented.

[0018] In the computer-readable storage medium of the present application, the method logic of any embodiment of the present application is encoded by a computer program and solidified in the storage medium, thereby providing a software implementation path to support the upgraded deployment of the gap detection function in the existing brake controller. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a flowchart of a vehicle control method according to an embodiment of the present application.

[0020] Figure 2 This application Figure 1 A flowchart including subroutines of a vehicle control method according to an embodiment.

[0021] Figure 3 This is a flowchart of a vehicle control method according to another embodiment of the present application.

[0022] Figure 4 This is a schematic diagram of the relationship between the motor angle, motor torque and time during a braking process in an embodiment of the present application.

[0023] Figure 5 This is a schematic diagram of the relationship between the motor current difference and the motor angle difference and time during a braking process in an embodiment of the present application.

[0024] Figure 6 This is a flowchart of a vehicle control method according to another embodiment of the present application.

[0025] Figure 7 This is a flowchart of a vehicle control method according to another embodiment of the present application.

[0026] Figure 8 It is a structural block diagram of the gap calculation device of an embodiment of the present application.

[0027] Figure 9 It is a structural block diagram of a vehicle according to an embodiment of the present application.

[0028] Figure 10 It is a structural schematic diagram of a vehicle according to another embodiment of the present application.

[0029] The following specific implementation methods will further illustrate the present application in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0030] In order to make the technical problems, technical solutions and beneficial effects solved by this application more clearly understood, this application is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0031] As a next-generation braking technology, automotive brake-by-wire systems are evolving towards eliminating pressure sensors. Their goal is to accurately output brake clamping force through algorithms, enabling vehicle deceleration, braking, and parking. The core challenge of this technology lies in establishing a highly reliable clamping force control model. However, over long-term operation, friction pads wear continuously, leading to a gradual increase in the gap between the pads and the brake disc. This physical change directly interferes with the accuracy of the clamping force algorithm: the increased gap significantly reduces the actual clamping force transmitted to the brake disc for the same motor stroke, resulting in safety hazards such as delayed braking response, insufficient braking force, and even parking failure. Therefore, the key bottleneck in the implementation of sensorless brake-by-wire technology is the ability to sense and compensate for disc gap changes in real time.

[0032] To address the disc gap problem, the industry currently adopts three main solutions: one is a compensation mechanism based on test data, which collects braking data under different wear conditions in bench or actual vehicle tests, establishes a gap-clamping force compensation mapping table, and statically embeds the compensation value in the control algorithm; the second is to dynamically correct the clamping force model, introduce the wear variation coefficient into the theoretical clamping force calculation model, and dynamically adjust the output parameters according to the preset wear mileage or usage time; the third is to install a wear detection sensor, integrate a thickness sensor or displacement sensor inside the brake, directly monitor the friction plate thickness or piston retraction position, and feed the data back to the control system.

[0033] However, in the above scheme, the bench / actual vehicle test data is limited by specific vehicle models, brake specifications and environmental conditions, and it is difficult to cover complex working conditions. The static compensation value cannot adapt to the dynamic wear process, and the model correction coefficient lacks a basis for real-time feedback. Both cannot guarantee the control accuracy of the braking system throughout its life cycle. For high-level braking systems involving driving safety, the applicability and safety of such empirical methods are questionable. Installing wear or displacement sensors inside the brake requires limited structural space, resulting in an increase in the axial size of the brake assembly, which conflicts with the requirement for a compact layout of the vehicle chassis. At the same time, the durability risk of the sensor under harsh working conditions such as high temperature and oil pollution further increases the complexity and cost of the system.

[0034] To this end, embodiments of the present application provide a vehicle control method, a vehicle, and a computer-readable storage medium, aiming to improve the problems of insufficient gap accuracy and poor feasibility of existing solutions.

[0035] In this application, the clearance between the brake disc (i.e., the friction pad and the brake disc) can be used to reflect the wear of the disc in the brake clamping force model. Therefore, the brake disc clearance refers to the maximum clearance, rather than the disc clearance at a certain moment in the braking process.

[0036] In this application, the brake clamping force model can be used to control vehicle braking in a pressure-free sensor-by-wire brake. It refers to a mathematical relationship that describes how the applied force (such as hydraulic or mechanical force) is converted into the actual normal clamping force acting on the friction pair (such as brake disc / pad) through the braking mechanism (taking into account factors such as leverage ratio and efficiency loss). This mathematical relationship can be calibrated through experimental data.

[0037] In this application, "the motor angle retracts to a completely non-working point" means that the motor is controlled to actively reverse a certain angle so that the internal mechanical transmission mechanism (such as gears, screws, etc.) completely eliminates the gap or preload force, and finally returns to the initial 0-position state without force and position deviation.

[0038] In this application, "one braking process" refers to the process from the start of braking to the release of braking.

[0039] Figure 1 It is a flowchart of a vehicle control method according to an embodiment of the present application. Figure 2 This application Figure 1 A flowchart including subroutines of a vehicle control method according to an embodiment.

[0040] This application first provides a vehicle control method, which is applied to the vehicle's motor braking process. For ease of description, it may also be referred to as "control method" or "method" below. Figure 1 As shown, the vehicle control method may include: Step S1: Acquire the first parameter and the second parameter of the motor.

[0041] Step S2: Determine a first time period based on a first parameter.

[0042] Step S3: Determine a second time period based on the second parameter.

[0043] Step S4: Obtain a verification value based on the first time period and the second time period.

[0044] Step S5: obtaining a clearance value between the friction pad and the brake disc in the brake based on the verification value and the rotation angle value of the motor in the first time period or the second time period.

[0045] Step S6: Outputting a corresponding calibration signal to the brake based on the gap value.

[0046] The first parameter includes the current value of the motor and the rate of change of the current value, and the second parameter includes the rotation angle value of the motor and the rate of change of the rotation angle value. Figure 2 As shown, in some embodiments, step S1 may specifically include: Step S101: Acquire the current value of the motor and the rate of change of the current value.

[0047] Step S102: Obtain the rotation angle value of the motor and the rate of change of the rotation angle value.

[0048] like Figure 2 As shown, step S2 may specifically include: Step S201: If the current value approaches or is equal to 0, the current moment is recorded as the first moment; if the rate of change of the current value is the maximum value, the current moment is recorded as the second moment.

[0049] Step S202: Determine the period between the first moment and the second moment as the first period.

[0050] like Figure 2 As shown, step S3 may specifically include: Step S301: If the rate of change of the rotation angle value is less than 0 or greater than 0, record the current moment as the third moment; if the rate of change of the rotation angle value is equal to 0, record the current moment as the fourth moment.

[0051] Step S302: Determine the period between the third moment and the fourth moment as the second period.

[0052] Step S101 may specifically include obtaining current values at multiple moments and determining the rate of change of the current values based on the current values at the multiple moments and the time differences between them. In this case, dynamically calculating the current rate of change based on the current values at the multiple moments and their corresponding time differences allows for real-time capture of the instantaneous variation of the current signal, reducing static sampling bias and providing response data (i.e., the rate of change of the current value) for determining the moment of disk separation.

[0053] The rate of change of the current value is obtained by the time difference between multiple moments, that is: In formula 1, i 1 is the current value at the next moment, i 0 is the current value at the previous moment, δt is the time difference, and c is the rate of change of the current value (i.e., it reflects how fast the current changes). Since the motor angular velocity is related to the motor current, c can also be used as a judgment value for sudden changes in the motor angular velocity change rate.

[0054] Step S102 may specifically include obtaining rotation angle values at multiple moments and determining the rate of change of the rotation angle values based on the rotation angle values at the multiple moments and the time differences between the multiple moments. In this case, calculating the rate of change of the rotation angle based on the rotation angle values at multiple moments and the time differences can reflect the changing trend of the motor speed in real time, accurately capturing the sudden change in angular acceleration at the moment of disk separation, and improving the reliability of determining the moment of disk separation.

[0055] The rate of change of the rotation angle value is obtained by the time difference between multiple moments, that is: In formula 2, φ 1 is the motor angle value at the next moment, φ 0 is the motor angle value at the previous moment, δt is the time difference, and d is the rate of change of the motor angle value. d can be used as a judgment value for a sudden change in the motor angle change rate.

[0056] Figure 3 This is a flowchart of a vehicle control method according to another embodiment of the present application.

[0057] In some embodiments, in the control method, step S1 (i.e., step S101 and step S102) may be executed in response to the vehicle being in a braking process or a braking release process. In other embodiments, in the control method, step S1 (i.e., step S101 and step S102) may be executed in response to the vehicle being in a braking process and a braking release process, with the braking process occurring before the braking release process.

[0058] For this reason, Figure 3 As shown, before step S101 and step S102, step S001 may be included: determining whether the vehicle meets a preset condition (for ease of distinction, referred to herein as the "first preset condition"). The first preset condition includes: the vehicle is in a braking process. In the embodiment of the present application, if the vehicle is in a braking process, steps S101 and S102 are executed, i.e., the motor current i and the motor angle are collected or obtained. φ And calculate the corresponding rate of change.

[0059] The basis for determining whether the vehicle is in the braking process includes: the presence of a brake pedal signal (driver-active braking scenario), or the presence of a braking signal input from the vehicle controller (autonomous driving system-triggered braking scenario), or the presence of a braking process signal such as a deceleration or wheel speed signal (vehicle dynamic braking effect verification scenario).

[0060] The brake pedal signal is generated directly by the driver's manual braking process, responding directly to driving inputs and serving as the most basic basis for braking triggering. The vehicle controller input brake signal is generated by automated braking triggered by autonomous driving systems (such as ACC and AEB) or the Electronic Stability Program (ESC). It covers braking requirements in intelligent driving scenarios and ensures that gap detection can still be activated even without human intervention. The braking process signal (deceleration / wheel speed signal) verifies the vehicle's actual deceleration status (such as anti-skid control and brake performance monitoring). It secondary confirms braking effectiveness through the vehicle's dynamic response, reducing false pedal signal triggering (such as accidentally pressing the pedal while parking) and improving detection reliability. These signals are used together to activate the disc gap detection process, ensuring that gap calculation is triggered only under valid braking conditions, thereby reducing false positives that interfere with system operation.

[0061] In step S201, the first moment is recorded as t β , and the second moment is recorded as t α , the time period between the first moment and the second moment is recorded as te, then step S202 has: Similarly, if Figure 3As shown, before step S201, the method may further include step S002: determining whether the current value approaches or is equal to 0. If the determination result is no, the current value and the rate of change of the current value are re-acquired. If the determination result is yes, the first moment is recorded, and the moment when the rate of change of the current value reaches the maximum is recorded as the second moment, that is, step S201 is continued. In this case, by cyclically determining whether the current is actually approaching 0 before recording the first moment, the moment is recorded only when it is confirmed that the condition is met. This can reduce the problem of erroneous marking of the return completion point due to instantaneous current fluctuations, thereby improving the definition accuracy of the first moment.

[0062] In step S301, the first moment is recorded as tβ’ , and record the second moment as tα’ , the time period between the first moment and the second moment is recorded as te' , then step S302 has: Similarly, if Figure 3 As shown, before step S301, the method further includes step S003: determining whether the rate of change of the rotation angle value matches the trend of the motor rotation angle retracting to a completely non-operating point. If the determination result is negative, the rotation angle value and the rate of change of the rotation angle value are reacquired. If the determination result is positive, the third and fourth moments are recorded. In this case, by verifying whether the rate of change of the rotation angle matches the physical state of the motor retracting to no load before recording the third and fourth moments, the moment is recorded only when the trend matches. This can filter out abnormal rotation angle signals (such as sudden changes caused by mechanical jamming), ensuring that the third and fourth moments correspond to the actual separation and retraction states.

[0063] It can be understood that during the brake release process, by capturing two dynamic event points when the piston retracts: the moment of disc separation (i.e., the second or fourth moment, the load drop causes a sharp change in the current change rate or a change in the rotation angle, at which time the gap is 0) and the moment of complete piston retraction (i.e., the first or third moment, the load disappears, causing the current to approach 0 or the rotation angle to be 0, at which time the gap is the largest point), the cross-validated verification value can be obtained in subsequent steps based on the sudden change characteristics of the motor current and the rotation angle change rate during the brake release process, and the disc gap value can be accurately calculated.

[0064] Figure 4 This is a schematic diagram of the relationship between the motor angle, motor torque and time during a braking process in an embodiment of the present application. Figure 5 This is a schematic diagram of the relationship between the motor current difference and the motor angle difference and time during a braking process in an embodiment of the present application.

[0065] In other embodiments, Figure 4As shown, calculations can also be based on the sudden changes in the motor current and rate of change of rotational angle during braking. For example, the first or third moment could be t1, when the disc is in its initial position (with maximum clearance), while the second or fourth moment could be t2, when the disc is in contact (with zero clearance). However, calculating the clearance by measuring the piston's travel from the theoretical fully released position (maximum clearance) to the disc contact point (with zero clearance) relies on displacement or current rise signals during the initial braking phase, making it susceptible to theoretical zero-point drift and interference from complex braking conditions.

[0066] In the embodiments of the present application, Figure 5 As shown, preferably, the disc separation moment is captured directly by turning the brake release process tα (Load drop causes sudden change in current rate) and the moment the piston fully retracts tβ (current tends to 0) two clear physical event points, and the gap is calculated by the dual-time angle difference, which can reduce the dependence on the theoretical zero point, realize double dynamic verification, significantly improve the detection accuracy and working condition robustness, and support active diagnosis in the parking state, which can provide a high-reliability gap monitoring solution for the sensorless wire control brake system.

[0067] Based on the difference between Equation 3 and Equation 4, step S400 can be: In Equation 5, a is the calibration value. This value can be used to determine the consistency of the sudden changes in the motor current and angle of change during the brake release process, ensuring the reliability and accuracy of the disc gap calculation in subsequent steps. For example, a can be a calibration value, with smaller a indicating better consistency.

[0068] Similarly, if Figure 3 As shown, before step S400, step S004 may be included: determining whether the vehicle meets a preset condition (referred to herein as the "second preset condition" for ease of distinction). The second preset condition includes the vehicle being in a braking process, the vehicle being in a braking release process, and the braking process preceding the braking release process. If the vehicle is not in a braking release process or the braking process does not precede the braking release process, the recorded or determined first moment, second moment, third moment, fourth moment, first time period, and second time period are cleared (i.e., step S402). If the vehicle is in a braking process and a braking release process, and the braking process precedes the braking release process, the first time period and the second time period are differentiated to obtain a verification value, and steps S400 and S500 are continued.

[0069] In this embodiment of the present application, the braking process in the second preset condition can be the same as that in the first preset condition. The determination basis for this braking process can be found above and will not be further elaborated here. The determination basis for the brake release process can be: when a brake pedal travel reduction signal, a brake release signal input by the vehicle controller, or a brake release process signal (e.g., a change in deceleration / wheel speed) is input to the brake-by-wire system, and if no change in the motor angle and angular velocity is detected, then the brake release state is determined to be valid. The brake pedal travel reduction signal is generated when the driver releases the brake pedal or the autonomous driving system issues a brake release command. It can identify a stuck fault based on the motor's non-responsiveness and trigger a safety alarm. The brake release signal input by the vehicle controller is generated during the automatic release process of the electronic parking brake (EPB). It can verify whether the motor has fully engaged and prevent accidental activation of the parking brake due to mechanical jamming. The brake release process signal is generated when multiple braking commands conflict (e.g., a conflict between a pedal signal and an autonomous driving command). It can be used to determine whether the system has truly entered the brake release phase based on the actual state of the actuator.

[0070] It can be understood that the difference between the first and second time periods is generated to generate a check value only when the vehicle meets the "brake → release" sequential logic. If the aforementioned operating conditions do not meet, all recorded data is cleared. This can eliminate interference from abnormal operating conditions (such as false triggering or disordered operation), ensure that the gap calculation is activated only during a valid brake release process, enhance the scenario applicability of the results, and further improve the reliability of the disc gap calculation.

[0071] In some embodiments, step S500 may specifically include: if the check value is less than or equal to a preset calibration value, calculating the brake disc clearance value based on a conversion relationship between the rotation angle value at the first moment, the rotation angle value at the second moment, and the brake configuration; or, if the check value is less than or equal to the preset calibration value, calculating the brake disc clearance value based on a conversion relationship between the rotation angle value at the third moment, the rotation angle value at the fourth moment, and the brake configuration. The brake configuration includes the lead of the piston screw and the ratio of the screw angle to the displacement of the friction pad in the brake (hereinafter referred to as the "drive ratio").

[0072] It can be understood that when the verification value passes the threshold (i.e., the preset calibration value), the disc gap value is converted based on the difference in the starting and ending angles of the first time period (or the second time period) combined with the screw lead and transmission ratio parameters. In this way, the motor angular displacement can be converted into a physical gap through the mechanical transmission relationship, realizing sensorless indirect measurement, and at the same time using the verification mechanism to ensure the availability of the output results.

[0073] Specifically, based on the piston stroke S in the brake and the motor angle φ The relationship: The motor angle in the first period te (or the second period te') can be obtained φ The relationship between the disc gap X is: In Equations 6 and 7, L is the piston screw lead, k is the transmission ratio, φβ is the motor angle value at the first moment, φα is the motor angle value at the second moment. For example, when the calibration value a (e.g., 0.05) is less than 0.1, the sudden change characteristics of the motor current and the angle change rate during the brake release process are highly consistent. In this case, the accurate disc gap value X can be calculated using Equation 7.

[0074] In an embodiment of the present application, after steps S1 to S6, the present application can provide an accurate calibration signal for the brake clamping force model based on the disc gap value. For example, the brake clamping force model can determine whether the output clamping force is normal based on the real-time disc gap value to accurately control the brake for braking.

[0075] Figure 6 This is a flowchart of a vehicle control method according to another embodiment of the present application. Figure 6 The difference between this embodiment and the above embodiment is that the control method may further include: Step S7: In response to receiving the parking signal, outputting a corresponding driving signal to the motor based on the gap value to control the vehicle to complete parking.

[0076] Further, through steps S1 to S7, the present application can output a normal parking clamping state signal based on the disc gap value to ensure the parking reliability of the entire vehicle. For example, when the vehicle needs to be parked, the brake clamping force model can output a normal parking clamping state signal based on the disc gap value to control the motor to move quickly and accurately to complete the parking process.

[0077] in addition, Figure 6 The sub-process, sub-steps and judgment conditions of the embodiment can be the same as those of the above embodiment, see the above Figures 1 to 5 The detailed description of the embodiments will not be repeated here.

[0078] Figure 7 This is a flowchart of a vehicle control method according to another embodiment of the present application. Figure 7 The difference between this embodiment and the above embodiment is that the control method may further include: Step S8: Outputting a corresponding safety redundancy signal to the brake based on the gap value.

[0079] Furthermore, through steps S1 to S8, the present application can also construct a functional safety redundancy mechanism for the wire control brake (such as providing a safety redundant signal), and improve the safety level of the vehicle braking system through multiple signal verification.

[0080] in addition, Figure 7 The sub-process, sub-steps and judgment conditions of the embodiment can be the same as those of the above embodiment, see the above Figures 1 to 5 The detailed description of the embodiments will not be repeated here.

[0081] It should also be noted that in the control method of the present application, steps S6, S7, and S8 are all actual control functions based on the clearance values obtained in steps S1 to S5. Therefore, steps S6, S7, and S8 can be set as one or more of them and the order can be unlimited. For example, the control method can include steps S6, S7, or S8, or the control method can include steps S6 and S7, and step S7 can precede step S6, or the control method can include steps S6 and S8, and step S8 can precede step S6, or the control method can include steps S6, S7, and S8, and step S7 or step S8 can precede step S6. In addition, during normal vehicle driving or maintenance (such as any of steps S6, S7, and S8), the present application can provide feedback of friction plate wear information to the driver and maintenance system (such as inferring the wear condition of the friction plate based on changes in the disc clearance value).

[0082] In the vehicle control method of the present application, a first time period is defined by obtaining the moment when the motor current approaches zero (first moment) and the moment when the current rate of change peaks (second moment) during the brake release process. Simultaneously, a second time period is defined by obtaining the moment when the motor's rotational angle rate of change is non-zero (third moment) and the moment when the rate of change returns to zero (fourth moment). A verification value is generated using the difference between the two time periods, and the disc clearance value is accurately calculated by combining the rotational angle value within the time period with the brake mechanical parameters. This method utilizes a redundant verification mechanism for both current and rotational angle signals, improving the reliability of clearance calculation through time-period cross-validation. This improves the reliability of clearance calculations, addressing the issues of insufficient clearance accuracy and poor feasibility of existing solutions. Specifically, the present application addresses the issues of brake signal distortion and parking clamp failure caused by increased disc clearance due to friction pad wear by dynamically calculating the current disc clearance value in real time.

[0083] Figure 8 It is a structural block diagram of the gap calculation device 1 according to an embodiment of the present application.

[0084] The present application also provides a gap calculation device 1, which is applied to the motor braking process of a vehicle, such as Figure 8As shown, the gap calculation device 1 may include: a detection module 11 for detecting the current data and angle data of the motor; a storage module 12 for storing data and programs; and a processing module 13 for executing programs to implement the method of any embodiment of the present application.

[0085] In the gap calculation device 1 of the present application, the detection module 11 (current / angle acquisition), the storage module 12 (data cache), and the processing module 13 are integrated into a single device, which can implement the gap detection process in hardware and provide an embedded solution for the wire control braking system.

[0086] In some embodiments, the gap calculation device 1 may include a CCU (Central Control Unit) or other controllers with data processing and control functions.

[0087] Figure 9 It is a structural block diagram of the vehicle 100 according to an embodiment of the present application.

[0088] The present application also provides a vehicle 100, such as Figure 9 As shown, vehicle 100 may include a clearance calculation device 1, a brake-by-wire system 2, and a primary zonal control unit (ZCU) 6, referred to as the "primary ZCU" for ease of distinction. Brake-by-wire system 2 is used for motor braking and may include a built-in brake clamping force model. Clearance calculation device 1 is used to implement the method of any embodiment of the present application to calculate brake disc clearance and transmit the calculation to the zonal control unit. The zonal control unit is used to output a calibration signal to brake-by-wire system 2 based on the brake disc clearance.

[0089] In the vehicle 100 of the present application, a gap output device is deployed, and the wire control brake 2 performs the braking action. The regional controller receives the gap value and calibrates the clamping force model, thereby forming a closed-loop control. The real-time gap data is used to dynamically optimize the braking force output to solve the problem of clamping force attenuation caused by wear.

[0090] In some embodiments, the brake-by-wire device 2 and the clearance calculation device 1 may be integrated into one body.

[0091] Figure 10 1 is a structural diagram of a vehicle 100 according to another embodiment of the present application. Figure 10 The dotted lines in the figure indicate signal connection relationships, and the solid lines indicate power supply connection relationships.

[0092] In some embodiments, as Figure 10As shown, vehicle 100 may further include wheel speed sensors 3, a brake system stability controller 4, a main power supply 8, a redundant zone controller 7 (referred to as "redundant ZCU"), and a redundant power supply 9. Wheel speed sensors 3 are used to detect the vehicle's wheel speed, brake system stability controller 4 is used to control the vehicle to maintain stability, main power supply 8 is used to provide power to various units or components, the redundant ZCU is used to provide the same control functions in the event of a failure of the main ZCU, and the redundant power supply 9 is used to provide power to various units or components in the event of an abnormality in main power supply 8.

[0093] As described in the above method, the present application can provide a verification signal of whether the brake clamping force model is valid, a parking normal clamping state signal, friction plate wear information, and a brake safety redundancy signal.

[0094] Among them, the specific process of providing a verification signal to indicate whether the brake clamping force model is valid includes: the main ZCU or redundant ZCU receives the actuation signals of the brake system stability controller 4 and the electronic brake pedal 5 and outputs a control instruction to the wire control brake 2; the wire control brake 2 inputs the motor torque signal, the motor angle signal and the wheel speed signal of the wheel speed sensor 3 into the gap output device; the CCU of the gap output device calculates and outputs the verification value and the disc gap value to the wire control brake 2, the main ZCU and the redundant ZCU based on each signal; the main ZCU and the redundant ZCU can calibrate the brake clamping force model based on the verification value and the disc gap value and determine whether it is valid; and the wire control brake 2 then completes the braking action.

[0095] The specific process of providing the parking normal clamping status signal includes: when the wire control brake 2 receives the parking signal from the main ZCU and the redundant ZCU, the parking normal clamping status signal can be accurately output based on the disc gap value output by the gap output device, thereby controlling the motor to move quickly to complete parking.

[0096] The specific process of providing friction plate wear information includes: during each complete braking process of the wire control brake 2, the gap output device can output the disc gap value, the main ZCU and the redundant ZCU can infer the wear condition of the friction plate based on the change of the disc gap value, and the main ZCU and the redundant ZCU provide the friction plate wear condition to the driver / maintenance equipment during the vehicle system / maintenance process.

[0097] The specific process for providing brake safety redundancy signals includes: When the clearance output device is operating, it outputs the disc clearance value in real time. At this time, the clamping force model built into the brake-by-wire system 2 verifies its output in real time. Simultaneously, the primary and redundant ZCUs use signals from the clearance output device and wheel speed sensor 3 to determine whether the vehicle is braking properly. This provides a redundant brake signal for the entire vehicle, enhancing the safety of the brake-by-wire system.

[0098] This application also provides a computer-readable storage medium (not shown) storing a computer program. When executed by a processor, the computer program implements the method of any embodiment of this application. The computer-readable storage medium of this application encodes the method logic of any embodiment of this application via the computer program and stores it in the storage medium. This provides a software-based implementation path, supporting the upgrade and deployment of gap detection functionality in existing brake controllers.

[0099] In this application, "a plurality" refers to two or more than two. In this application, unless otherwise expressly defined, the terms "installed", "connected", and "connected" 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, or it can be internal communication between two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0100] The terms "first," "second," "third," and "fourth," if any, in this application are used to distinguish similar objects and do not necessarily describe a specific order or precedence. The term "and / or" in this application simply describes a relationship between related objects, indicating that three possible relationships exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, or B exists alone. Furthermore, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0101] Unless otherwise specified, all steps of the present application may be performed sequentially or randomly. For example, a statement that the method includes steps A and B indicates that the method may include steps A and B performed sequentially, or steps B and A performed sequentially. For example, a statement that the method may also include step C indicates that step C may be added to the method in any order, for example, the method may include steps A, B, and C, or steps A, C, and B, or steps C, A, and B, etc.

[0102] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A vehicle control method, characterized in that: The vehicle includes a motor and a brake, and the method includes: Acquire a first parameter and a second parameter of the motor, wherein the first parameter includes a current value of the motor and a rate of change of the current value, and the second parameter includes a rotation angle value of the motor and a rate of change of the rotation angle value; determining a first time period based on the first parameter; determining a second time period based on the second parameter; Obtaining a verification value based on the first time period and the second time period; Obtaining a clearance value between a friction plate and a brake disc in the brake based on the verification value and the rotation angle value of the motor in the first time period or the second time period; A corresponding calibration signal is output to the brake based on the gap value.

2. The control method according to claim 1, characterized in that: The method comprises: In response to the vehicle being in a braking process or a braking release process, executing the step of obtaining the first parameter and the second parameter of the motor; Among them, the vehicle's braking process includes receiving a brake pedal signal, a vehicle controller inputting a braking signal or a braking process signal, and the vehicle's braking release process includes receiving a brake pedal stroke reduction signal, a vehicle controller inputting a braking release signal or a braking release process signal.

3. The control method according to claim 1, wherein: The method comprises: In response to the vehicle undergoing a braking process and a braking release process, wherein the braking process precedes the braking release process, executing the step of acquiring the first parameter and the second parameter of the motor; Among them, the vehicle's braking process includes receiving a brake pedal signal, a vehicle controller inputting a braking signal or a braking process signal, and the vehicle's braking release process includes receiving a brake pedal stroke reduction signal, a vehicle controller inputting a braking release signal or a braking release process signal.

4. The control method according to claim 1, wherein: The determining the first time period based on the first parameter includes: Determine the moment when the current value approaches or is equal to 0 as the first moment; Determining the moment when the rate of change of the current value is maximum as the second moment; A period from the first moment to the second moment is determined as the first period.

5. The control method according to claim 4, characterized in that: Also includes: Determine the moment when the rate of change of the rotation angle value is less than 0 or greater than 0 as the third moment; Determine the moment when the rate of change of the rotation angle value is equal to 0 as the fourth moment; The period from the third moment to the fourth moment is determined as the second period.

6. The control method according to claim 5, characterized in that: The obtaining of the clearance value between the friction plate and the brake disc in the brake based on the verification value and the rotation angle value of the motor in the first time period or the second time period includes: If the verification value is less than or equal to a preset calibration value, the clearance value is calculated based on the conversion relationship between the rotation angle value at the first moment, the rotation angle value at the second moment, and the brake configuration; or, If the check value is less than or equal to a preset calibration value, calculating the clearance value based on a conversion relationship between the rotation angle value at the third moment, the rotation angle value at the fourth moment, and the brake configuration; The brake configuration includes the lead of the piston screw and the ratio of the screw rotation angle to the displacement of the friction plate in the brake.

7. The control method according to claim 1, characterized in that: The obtaining of the first parameter and the second parameter of the motor includes: Obtaining current values at multiple moments, and obtaining a rate of change of the current values based on the current values at the multiple moments and the time differences between the multiple moments; and / or, The rotation angle values at a plurality of moments are acquired, and the change rate of the rotation angle value is acquired based on the rotation angle values at the plurality of moments and the time difference between the plurality of moments.

8. The control method according to claim 1, characterized in that: The method further comprises: In response to receiving a parking signal, outputting a corresponding driving signal to the motor based on the gap value to control the vehicle to complete parking; or, A corresponding safety redundancy signal is output to the brake based on the gap value.

9. A vehicle, characterized in that: The invention comprises a wire-controlled brake, a gap calculation device and a zone controller, wherein the wire-controlled brake is used for motor braking; the gap calculation device is used to implement the method described in any one of claims 1 to 8 to calculate the gap value between the friction plate and the brake disc in the brake and send it to the zone controller; the zone controller is used to output a calibration signal to the wire-controlled brake based on the gap value.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 8 is implemented.

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