Method and device for measuring abrasion loss of friction plate

Abstract

The embodiment of the invention relates to the technical field of motor detection, and discloses a friction plate abrasion loss measuring method, which comprises the following steps: controlling a brake execution motor to reversely rotate according to a set mode until the brake execution motor reaches a reverse limiting position; a first accumulative reverse rotation angle of the braking execution motor is obtained; the brake execution motor is controlled to rotate forwards according to a set mode until the friction plate makes contact with the disc face of the brake disc; the accumulated forward rotation angle of the brake execution motor is obtained, and the current axial position of the friction plate is obtained through calculation according to the accumulated forward rotation angle and an axial displacement formula; and calculating the abrasion loss of the corresponding friction plate according to the current axial position and the initial axial position. According to the friction plate abrasion loss measuring method, the displacement amount of the motor in the axial position is determined by obtaining the rotation angle of the braking execution motor, and then accurate detection of the abrasion loss of the friction plate is achieved.

Description

Technical Field

[0001] The invention relates to the field of automobile technology, and in particular to a method and a device for measuring the wear amount of a friction plate. Background Art

[0002] Traditional hydraulic brake systems do not have quantitative and accurate measurements of friction pads. Traditional friction pad wear detection mainly includes grounding and grinding lines, which have the following advantages and disadvantages:

[0003] Grounding type: Grounding type wear detection has a simple structure and low cost. When the friction plate is worn to the trigger position, the grounding on the friction plate rubs against the brake disc to make a sharp noise to remind the user to replace the friction plate. If it is not replaced in time, the friction between the grounding and the brake disc will cause irreversible damage to the brake disc, and it is impossible to "warn in advance" and provide users with sufficient replacement time.

[0004] Grinding line type: Grinding line type adds a sensor line to the friction plate. When the wear continues to a certain extent, the sensor line will be worn off. The ECU receives the open circuit signal of the sensor and turns on the fault light to alert the user. This method is relatively expensive and increases the difficulty of installation. The feedback method is too simple and cannot detect whether the open circuit is caused by a wiring harness problem, so there will often be "false alarms" and other situations.

[0005] No matter which form of friction plate wear detection is used, it can only alarm the friction plate that is about to be worn out to remind the user to replace the friction plate in time, but there is no quantitative detection of the specific amount of wear of the friction plate. Therefore, designing a solution that can accurately measure wear has become a technical problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0006] In view of the above-mentioned defects, an embodiment of the present invention discloses a method for measuring the wear of a friction plate, which can realize fast and accurate measurement of the wear of the friction plate.

[0007] A first aspect of an embodiment of the present invention discloses a method for measuring friction plate wear, comprising:

[0008] Acquiring vehicle status information in a parking state, and matching the vehicle status information with a preset judgment logic to determine whether to enter a wear measurement step;

[0009] After entering the wear measurement step, controlling the brake actuator motor to rotate in the reverse direction according to a set mode until the brake actuator motor reaches a reverse limit position;

[0010] Obtaining a first cumulative reverse rotation angle of the brake actuator motor, and comparing the first cumulative reverse rotation angle with the second cumulative reverse rotation angle measured last time to determine whether the brake actuator motor successfully reaches the reverse limit position, and if so, executing the next step;

[0011] The current axial position of the friction plate is calculated according to the first accumulated reverse rotation angle and the axial displacement formula, wherein the axial position formula is: S=k*α, wherein S is the current axial position, k is the axial displacement corresponding to the unit angle of rotation of the motor, and α is the first accumulated reverse rotation angle;

[0012] The wear amount of the corresponding friction plate is calculated according to the current axial position and the initial axial position.

[0013] A second aspect of an embodiment of the present invention discloses a method for measuring friction plate wear, comprising:

[0014] Acquiring vehicle status information in a parking state, and matching the vehicle status information with a preset judgment logic to determine whether to enter a wear measurement step;

[0015] After entering the wear measurement step, controlling the brake actuator motor to rotate in the reverse direction according to a set mode until the brake actuator motor reaches a reverse limit position;

[0016] Obtaining a first cumulative reverse rotation angle of the brake actuator motor, and comparing the first cumulative reverse rotation angle with the second cumulative reverse rotation angle measured last time to determine whether the brake actuator motor successfully reaches the reverse limit position, and if so, executing the next step;

[0017] Control the brake actuator motor to rotate in the forward direction according to the set mode until the friction plate contacts the brake disc surface;

[0018] The accumulated positive rotation angle of the brake actuator motor is obtained, and the current axial position of the friction plate is calculated according to the accumulated positive rotation angle and the axial displacement formula; the axial position formula is: S=k*α, where S is the current axial position, k is the axial displacement corresponding to the unit angle of motor rotation, and α is the accumulated positive rotation angle;

[0019] The wear amount of the corresponding friction plate is calculated according to the current axial position and the initial axial position.

[0020] As an optional implementation, in the second aspect of the embodiment of the present invention, after entering the wear measurement step, controlling the brake actuator motor to rotate in the reverse direction according to a set mode until the brake actuator motor reaches a reverse limit position includes:

[0021] After entering the wear measurement step, the front wheel brake actuator motor is controlled to rotate forward to perform a re-clamping operation, and the rear wheel brake actuator motor is controlled to rotate reversely according to a set mode until the rear wheel brake actuator motor reaches a reverse limit position.

[0022] In order to achieve safer friction pad wear measurement, when conducting specific inspections, it is necessary to clamp the front wheel or the rear wheel to prevent brake failure during the wear measurement process, and then measure the wear of the friction pad at the other wheel.

[0023] As an optional implementation, in the second aspect of the embodiment of the present invention, after the wear amount of the corresponding friction plate is calculated according to the current axial position and the initial axial position, the method further includes:

[0024] The current axial position, the accumulated reverse rotation angle and the current mileage are stored in a storage module.

[0025] After each measurement, the corresponding data is stored; this makes it easier to extract and compare data next time, and when performing specific implementation, the current data can be used to overwrite the previous data, which can further reduce the pressure on data storage caused by the measurement data.

[0026] As an optional implementation, in the second aspect of the embodiment of the present invention, the vehicle status information includes ignition key status, vehicle speed, gear status, longitudinal acceleration, lateral acceleration, current mileage, and parking status;

[0027] The step of matching the vehicle status information with a preset judgment logic to determine whether to enter the wear measurement step includes:

[0028] When the ignition key is off, the vehicle speed is zero, the gear is in the parking gear, the longitudinal acceleration and the lateral acceleration are both less than the first set threshold, and the difference between the current mileage and the mileage last measured is greater than the second set threshold, the control enters the wear measurement step.

[0029] In this embodiment, a variety of conditions are combined to determine whether to enter the wear measurement step. By using a full range of conditions for comprehensive judgment, the stability after entering the wear measurement is higher and safety problems are less likely to occur.

[0030] As an optional implementation, in the second aspect of the embodiment of the present invention, controlling the brake actuator motor to rotate in the reverse direction according to the set mode until the brake actuator motor reaches the reverse limit position includes:

[0031] Controlling the brake execution motor to enter a first acceleration state, a second acceleration state, and a third acceleration state respectively to control the brake execution motor to perform a rotation acceleration process until the speed of the brake execution motor reaches a first set speed;

[0032] Controlling the brake actuator motor to enter a uniform speed running state, in which the brake actuator motor runs at a first set speed for a set time;

[0033] Controlling the brake execution motor to enter a first deceleration state, a second deceleration state, and a third deceleration state respectively to control the brake execution motor to perform a rotation deceleration process until the rotation speed of the brake execution motor reaches a second set rotation speed;

[0034] When it is detected that the brake actuating motor stops rotating, it is determined that the brake actuating motor reaches a reverse limit position;

[0035] The controlling the brake actuator motor to rotate in a forward direction according to a set mode until the friction plate contacts the surface of the brake disc comprises:

[0036] Controlling the brake execution motor to enter a fourth acceleration state, a fifth acceleration state, and a sixth acceleration state respectively to control the brake execution motor to perform a rotation acceleration process until the speed of the brake execution motor reaches a third set speed;

[0037] Controlling the brake actuator motor to enter a uniform speed running state, in which the brake actuator motor runs at a third set speed for a set time;

[0038] Controlling the brake execution motor to enter a fourth deceleration state, a fifth deceleration state, and a sixth deceleration state respectively to control the brake execution motor to perform a rotation deceleration process until the rotation speed of the brake execution motor reaches a second set rotation speed;

[0039] When it is detected that the current sensor disposed at the brake actuating motor and / or the rotational acceleration meet the set conditions, it is determined that the friction plate contacts the disc surface of the brake disc.

[0040] By adopting the above-mentioned S-curve control method and reverse S-curve control method, the stability of the overall motor control is further improved. Under the premise of ensuring efficiency, the impact of excessive motor speed on the motor can be further reduced, thereby increasing the service life of the motor.

[0041] As an optional implementation, in the second aspect of the embodiment of the present invention, after the wear amount of the corresponding friction plate is calculated according to the current axial position and the initial axial position, the method further includes:

[0042] Data matching is performed based on the wear amount of the friction plate and a preset wear-stiffness mapping table to determine the stiffness data of the current friction plate.

[0043] The estimation of the final execution clamping force of the EMB system needs to be calculated based on the stiffness of the current system, which includes the stiffness of the caliper and the stiffness of the friction plate. The stiffness of the caliper can be regarded as a constant, while the stiffness of the friction plate varies greatly under different wear amounts. According to experiments, the impact on the final model calculation results can reach more than 30%. Based on this, the friction plate stiffness can be calculated by looking up the table according to different friction plate wear amounts, providing reliable model parameters for the model calculation, making the final clamping force results more accurate.

[0044] A third aspect of an embodiment of the present invention discloses a method for measuring friction plate wear, comprising:

[0045] A first acquisition module: used for acquiring vehicle status information in a parking state, and matching the vehicle status information with a preset judgment logic to determine whether to enter a wear measurement step;

[0046] Reverse rotation module: used for controlling the brake actuator motor to rotate in the reverse direction according to a set mode until the brake actuator motor reaches a reverse limit position after entering the wear measurement step;

[0047] The second acquisition module is used to acquire the first cumulative reverse rotation angle of the brake execution motor, and compare the first cumulative reverse rotation angle with the second cumulative reverse rotation angle measured last time to determine whether the brake execution motor successfully reaches the reverse limit position, and if so, execute the next step;

[0048] Forward rotation module: used to control the brake actuator motor to rotate forward according to the set mode until the friction plate contacts the brake disc surface;

[0049] The third acquisition module is used to obtain the cumulative positive rotation angle of the brake execution motor, and calculate the current axial position of the friction plate according to the cumulative positive rotation angle and the axial displacement formula; the axial position formula is: S = k*α, where S is the current axial position, k is the axial displacement corresponding to the unit angle of motor rotation, and α is the cumulative positive rotation angle;

[0050] Wear amount determination module: used for calculating the wear amount of the corresponding friction plate according to the current axial position and the initial axial position.

[0051] The fourth aspect of an embodiment of the present invention discloses an electronic device, comprising: a memory storing executable program code; a processor coupled to the memory; the processor calls the executable program code stored in the memory to execute the friction plate wear measurement method disclosed in the first aspect of the embodiment of the present invention.

[0052] A fifth aspect of an embodiment of the present invention discloses a computer-readable storage medium storing a computer program, wherein the computer program enables a computer to execute the friction plate wear measurement method disclosed in the first aspect of an embodiment of the present invention.

[0053] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0054] The friction plate wear measurement method in the embodiment of the present invention determines the displacement of the motor in the axial position by acquiring the rotation angle of the brake actuator motor, thereby achieving accurate detection of the friction plate wear. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0056] Figure 1 It is a schematic flow chart of a friction plate wear measurement method disclosed in an embodiment of the present invention;

[0057] Figure 2 It is a schematic diagram of a process of controlling a brake execution motor to rotate to a reverse limit position disclosed in an embodiment of the present invention;

[0058] Figure 3 It is a schematic diagram of a process of controlling the friction plate to contact the brake disc surface disclosed in an embodiment of the present invention;

[0059] Figure 4 It is a schematic diagram of the structure of the EMB system friction plate wear measurement system disclosed in an embodiment of the present invention;

[0060] Figure 5 is a schematic diagram of clamping and releasing displacement of the friction plate before and after wear disclosed in an embodiment of the present invention;

[0061] Figure 6 is a schematic diagram of the rotation speed of the motor when released according to an embodiment of the present invention;

[0062] Figure 7 It is a schematic flow chart of another friction plate wear measurement method disclosed in an embodiment of the present invention;

[0063] Figure 8 It is a structural schematic diagram of a friction plate wear measurement device provided by an embodiment of the present invention;

[0064] Fig. 9 It is a structural schematic diagram of an electronic device provided by an embodiment of the present invention.

[0065] Figure numerals: 1. brake disc; 2. friction plate; 3. piston; 4. brake actuator motor; 5. current sensor; 6. MPS sensor; 7. electronic control unit. DETAILED DESCRIPTION

[0066] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0067] It should be noted that the terms "first", "second", "third", "fourth", etc. in the specification and claims of the present invention are used to distinguish different objects rather than to describe a specific order. The terms "including" and "having" in the embodiments of the present invention and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device including a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0068] Regardless of the form of friction plate wear detection, it can only alarm the friction plate that is about to be worn out to remind the user to replace the friction plate in time, and there is no quantitative detection of the specific amount of wear of the friction plate. Based on this, the embodiment of the present invention discloses a friction plate wear measurement method, device, electronic device and storage medium, which determines the displacement of the motor in the axial position by obtaining the rotation angle of the brake actuator motor, thereby realizing accurate detection of the friction plate wear.

[0069] Embodiment 1

[0070] See also Figure 1 , Figure 1 It is a flow chart of the friction plate wear measurement method disclosed in the embodiment of the present invention. Among them, the execution subject of the method described in the embodiment of the present invention is an execution subject composed of software and / or hardware, and the execution subject can receive relevant information by wired or / and wireless means, and can send certain instructions. Of course, it can also have certain processing functions and storage functions. The execution subject can control multiple devices, such as a remote physical server or cloud server and related software, or it can be a local host or server and related software that performs related operations on a device placed somewhere. In some scenarios, multiple storage devices can also be controlled, and the storage devices can be placed in the same place or different places as the devices. For example Figures 1 to 6 As shown, the friction plate wear measurement method includes the following steps:

[0071] S101: acquiring vehicle status information in a parking state, and matching the vehicle status information with a preset judgment logic to determine whether to enter a wear measurement step;

[0072] More preferably, the vehicle status information includes ignition key status, vehicle speed, gear status, longitudinal acceleration, lateral acceleration, current mileage, and parking status;

[0073] The step of matching the vehicle status information with a preset judgment logic to determine whether to enter the wear measurement step includes:

[0074] When the ignition key is off, the vehicle speed is zero, the gear is in the parking gear, the longitudinal acceleration and the lateral acceleration are both less than the first set threshold, and the difference between the current mileage and the mileage last measured is greater than the second set threshold, the control enters the wear measurement step.

[0075] In this embodiment, a combination of multiple conditions is used to determine whether to enter the wear measurement step. By using a full range of conditions for comprehensive judgment, the stability after entering the wear measurement is higher and safety problems are less likely to occur. This step is mainly to determine whether to enter the wear measurement. The wear measurement is entered only when all conditions are met. If the above conditions are not met, the control is in the parking state.

[0076] S102: After entering the wear measurement step, controlling the brake actuator motor to rotate in the reverse direction according to a set mode until the brake actuator motor reaches a reverse limit position;

[0077] More preferably, after entering the wear measurement step, controlling the brake actuator motor to rotate in the reverse direction according to a set mode until the brake actuator motor reaches a reverse limit position includes:

[0078] After entering the wear measurement step, the front wheel brake actuator motor is controlled to rotate forward to perform a re-clamping operation, and the rear wheel brake actuator motor is controlled to rotate reversely according to a set mode until the rear wheel brake actuator motor reaches a reverse limit position.

[0079] In order to achieve safer friction pad wear measurement, when conducting specific inspections, it is necessary to clamp the front wheel or the rear wheel to prevent brake failure during the wear measurement process, and then measure the wear of the friction pad at the other wheel.

[0080] When performing specific measurements, the wear measurement can be performed on the front two wheels first, or the wear measurement can be performed on the rear two wheels. When the wear measurement is performed on the front two wheels, the rear two wheels can be clamped again to put the vehicle in a stable parking state, and the front two wheels can be released by reverse rotation; when the wear measurement is performed on the rear two wheels, the front two wheels can be clamped again to put the vehicle in a stable parking state, and the rear two wheels can be released by reverse rotation. More preferably, Figure 2 is a schematic diagram of a process of controlling the braking execution motor to rotate to a reverse limit position disclosed in an embodiment of the present invention, such as Figure 2 As shown, the control of the brake execution motor to rotate in the reverse direction according to the set mode until the brake execution motor reaches the reverse limit position includes:

[0081] S1021: Controlling the brake actuator motor to enter a first acceleration state, a second acceleration state, and a third acceleration state respectively to control the brake actuator motor to perform a rotation acceleration process until the speed of the brake actuator motor reaches a first set speed;

[0082] S1022: Controlling the brake actuator motor to enter a uniform speed running state, in which the brake actuator motor runs at a first set speed for a set time;

[0083] S1023: Controlling the brake actuator motor to enter a first deceleration state, a second deceleration state, and a third deceleration state respectively to control the brake actuator motor to perform a rotation deceleration process until the rotation speed of the brake actuator motor reaches a second set rotation speed;

[0084] S1024: When it is detected that the brake actuating motor stops rotating, determining that the brake actuating motor reaches a reverse limit position;

[0085] In order to ensure that the measurement time is short and the motor control is smooth, when releasing, the speed adopts the S-curve control method during acceleration and the reverse S-curve control method during deceleration; the acceleration and deceleration are expressed by the absolute value of the speed change rate;

[0086] The acceleration and deceleration control method is to use a control method of acceleration-uniform acceleration-deceleration when accelerating, and a control method of acceleration-deceleration-uniform deceleration-deceleration when decelerating, as shown in the attached Figure 6 As shown:

[0087] In the first stage, the acceleration stage, the motor first enters the acceleration state, which is the first acceleration state mentioned above. When the acceleration reaches the maximum value Amotaccmax, the motor enters the uniform acceleration state to maintain the acceleration Amotaccmax, which is the second acceleration state mentioned above. After a period of time, the motor enters the deceleration state, which is the third acceleration state mentioned above.

[0088] When the acceleration Amotacc = 0, the speed reaches the maximum speed Vmotspdmax and enters the second stage, the uniform speed maintenance stage, maintaining the maximum speed Vmotspdmax;

[0089] After a period of uniform speed, it enters the third stage. In the deceleration stage, the deceleration first enters the acceleration and deceleration state. When the deceleration reaches the maximum value Amotdecmax, the motor enters the uniform deceleration state and maintains the deceleration Amotdecmax. After a period of time, it enters the deceleration state again.

[0090] When the speed is decelerated to Vtouch, the uniform speed is maintained; by default, the actuator motor has a reverse mechanical limit. When the motor's cumulative reverse angle ReverseAngle no longer increases and the motor speed is zero, it is determined that the reverse limit has been reached. This reverse limit position is also the motor zero position.

[0091] S103: Obtaining a first accumulated reverse rotation angle of the brake actuator motor, and comparing the first accumulated reverse rotation angle with the second accumulated reverse rotation angle measured last time to determine whether the brake actuator motor has successfully reached the reverse limit position, and if so, executing the next step;

[0092] The difference ΔReserveAngle between the motor cumulative reverse rotation angle of each rear wheel during this measurement and the motor cumulative reverse rotation angle of each rear wheel measured last time is used to determine whether the motor has actually reached the reverse limit position. If ΔReserveAngle≥0, it is determined that the motor has successfully reached the reverse limit at this time, and the motor cumulative forward rotation angle ForwardAngle=0 of the motor position of each rear wheel at this time is recorded.

[0093] S104: Controlling the brake actuator motor to rotate forward according to a set mode until the friction plate contacts the surface of the brake disc;

[0094] Figure 3 is a schematic diagram of a process of controlling the friction plate to contact the brake disc surface disclosed in an embodiment of the present invention, such as Figure 3 As shown, the control of the brake execution motor to rotate forward according to the set mode until the friction plate contacts the disc surface of the brake disc includes:

[0095] S1041: Controlling the brake actuator motor to enter a fourth acceleration state, a fifth acceleration state, and a sixth acceleration state respectively to control the brake actuator motor to perform a rotation acceleration process until the speed of the brake actuator motor reaches a third set speed;

[0096] S1042: Controlling the brake actuator motor to enter a uniform speed running state, in which the brake actuator motor runs at a third set speed for a set time;

[0097] S1043: Controlling the brake actuator motor to enter a fourth deceleration state, a fifth deceleration state, and a sixth deceleration state respectively to control the brake actuator motor to perform a rotation deceleration process until the rotation speed of the brake actuator motor reaches a second set rotation speed;

[0098] S1044: When it is detected that the current sensor and / or the rotational acceleration disposed at the brake actuator motor meets the set conditions, it is determined that the friction plate contacts the disc surface of the brake disc.

[0099] By adopting the above-mentioned S-curve control method and reverse S-curve control method, the stability of the overall motor control is further improved. Under the premise of ensuring efficiency, the impact of excessive motor speed on the motor can be further reduced, thereby increasing the service life of the motor.

[0100] The rear wheel friction plate starts from the reverse limit and is clamped in the forward direction. To ensure a short measurement time and smooth motor control, the acceleration and deceleration during clamping also use S-shaped curves and reverse S-shaped curves to control the speed, as shown in the attached figure. Figure 6 As shown:

[0101] In the first stage, the acceleration stage, the motor first enters the acceleration state. When the acceleration reaches the maximum value Amotaccmax, the motor enters the uniform acceleration state to maintain the acceleration Amotaccmax, and then enters the deceleration state after a period of time.

[0102] When the acceleration Amotacc = 0, the speed reaches the maximum speed Vmotspdmax and enters the second stage, the uniform speed maintenance stage, maintaining the maximum speed Vmotspdmax;

[0103] After a period of uniform speed, it enters the third stage. In the deceleration stage, the deceleration first enters the acceleration and deceleration state. When the deceleration reaches the maximum value Amotdecmax, the motor enters the uniform deceleration state and maintains the deceleration Amotdecmax. After a period of time, it enters the deceleration state again.

[0104] When the speed is decelerated to Vtouch, maintain a constant speed;

[0105] When the motor speed is less than the threshold value, and the deceleration is greater than the threshold value, it is considered that the friction plate has just touched the disk surface, and the accumulated forward rotation angle ForwardAngle of the motors of each rear wheel is recorded. Because when the disk surface is touched, the deceleration of the motor speed will change, and the motor current will also change. When the changes in the two are detected, it is determined that the friction plate is in contact with the disk surface and the motor is controlled to stop. In the embodiment of the present invention, more accurate data measurement can be achieved through forward detection, because in the clamped state, the friction plate will produce a certain deformation, which will reduce the accuracy of the measurement. Only when the friction plate just touches the disk surface, the measurement result is more accurate.

[0106] The above only uses the rear wheel to perform a specific wear measurement mode, but for the front wheel, the control logic and method are the same as above.

[0107] S105: Obtain the cumulative positive rotation angle of the brake actuator motor, and calculate the current axial position of the friction plate according to the cumulative positive rotation angle and the axial displacement formula; the axial position formula is: S=k*α, where S is the current axial position, k is the axial displacement corresponding to the motor rotation unit angle, and α is the cumulative positive rotation angle;

[0108] S106: Calculate the wear amount of the corresponding friction plate according to the current axial position and the initial axial position.

[0109] like Figure 4 As shown, the friction plate 2 is installed on the piston 3, and the brake actuator motor 4 drives the piston to move so that the friction plate 2 contacts and separates with the brake disc 1 to achieve braking; a current sensor 5 is set at the brake actuator motor 4 to detect the operating current state of the motor, and an MPS sensor 6 is set at the brake actuator motor 4 to detect the rotation angle of the motor; the overall control and detection are achieved through the electronic control unit 7.

[0110] like Figure 5 As shown, s1 represents the displacement of the friction plate when the motor rotates forward during the initial measurement, and s2 represents the displacement of the friction plate when the motor rotates forward during this measurement; according to the displacement of each friction plate of the four wheels measured this time and the displacement of each friction plate of the four wheels measured initially, the wear amount of each friction plate of the four wheels is calculated: Δs = s1-s2

[0111] More preferably, after calculating the wear amount of the corresponding friction plate according to the current axial position and the initial axial position, the method further includes:

[0112] The current axial position, the accumulated reverse rotation angle and the current mileage are stored in a storage module.

[0113] After each measurement, the corresponding data is stored; this makes it easier to extract and compare data next time, and when performing specific implementation, the current data can be used to overwrite the previous data, which can further reduce the pressure on data storage caused by the measurement data.

[0114] More preferably, after calculating the wear amount of the corresponding friction plate according to the current axial position and the initial axial position, the method further includes:

[0115] Data matching is performed based on the wear amount of the friction plate and a preset wear-stiffness mapping table to determine the stiffness data of the current friction plate.

[0116] The estimation of the final execution clamping force of the EMB system needs to be calculated based on the stiffness of the current system, which includes the stiffness of the caliper and the stiffness of the friction plate. The stiffness of the caliper can be regarded as a constant, while the stiffness of the friction plate varies greatly under different wear amounts. According to experiments, the impact on the final model calculation results can reach more than 30%. Based on this, the friction plate stiffness can be calculated by looking up the table according to different friction plate wear amounts, providing reliable model parameters for the model calculation, making the final clamping force results more accurate.

[0117] The embodiment of the present invention calculates the wear of the friction plate by measuring the change in the total motor rotation angle from the start of the movement of the actuator motor from the reverse limit to the end of the contact with the brake disc. After every 1,500 kilometers of driving, turn off the ignition switch after parking on a horizontal road, and then independently control the front and rear wheel motors to perform corresponding wear detection; first, through the preset speed control algorithm in the EMB system electronic control unit ECU, use the S-shaped control method for acceleration and the reverse S-shaped control method for deceleration to release the rear wheel motor to the reverse limit, and then use the same control algorithm to clamp the rear wheel motor until it contacts the brake disc, and then release the clamped front wheel motor with the same control method. Before the motor is released, the other side motor needs to be clamped again to ensure parking reliability, and the total motor rotation angle when the four wheels are clamped is recorded respectively. The axial displacement of the friction plate is calculated according to the total motor rotation angle when the four wheels are clamped, and the friction plate wear is calculated by comparing it with the axial displacement of the friction plate during the initial measurement. The friction plate wear measurement method in the embodiment of the present invention determines the displacement of the motor in the axial position by obtaining the rotation angle of the brake actuator motor, thereby realizing accurate detection of the friction plate wear.

[0118] Embodiment 2

[0119] like Figure 7 As shown, this embodiment provides a friction plate wear measurement method, comprising:

[0120] S201: Acquire vehicle status information in a parking state, and match the vehicle status information with a preset judgment logic to determine whether to enter a wear measurement step;

[0121] S202: After entering the wear measurement step, controlling the brake actuator motor to rotate in the reverse direction according to a set mode until the brake actuator motor reaches a reverse limit position;

[0122] S203: Obtaining a first accumulated reverse rotation angle of the brake actuator motor, and comparing the first accumulated reverse rotation angle with the second accumulated reverse rotation angle measured last time to determine whether the brake actuator motor has successfully reached the reverse limit position, and if so, executing the next step;

[0123] S204: Calculate the current axial position of the friction plate according to the first accumulated reverse rotation angle and the axial displacement formula, wherein the axial position formula is: S=k*α, where S is the current axial position, k is the axial displacement corresponding to a unit angle of motor rotation, and α is the first accumulated reverse rotation angle;

[0124] S205: Calculate the wear amount of the corresponding friction plate according to the current axial position and the initial axial position.

[0125] Compared with the first embodiment, the above method obtains the corresponding rotation amount during the movement to the reverse limit to achieve the measurement of the wear amount, without the need for positive rotation determination.

[0126] Embodiment 3

[0127] See also Figure 8 , Figure 8 FIG. 1 is a schematic diagram of the structure of the friction plate wear measurement device disclosed in an embodiment of the present invention. Figure 8 As shown, the friction plate wear measurement device may include:

[0128] The first acquisition module 21 is used to acquire the vehicle state information in the parking state, and match the vehicle state information with the preset judgment logic to determine whether to enter the wear measurement step;

[0129] Reverse rotation module 22: used for controlling the brake actuator motor to rotate in the reverse direction according to a set mode until the brake actuator motor reaches a reverse limit position after entering the wear measurement step;

[0130] The second acquisition module 23 is used to acquire the first cumulative reverse rotation angle of the brake execution motor, and compare the first cumulative reverse rotation angle with the second cumulative reverse rotation angle measured last time to determine whether the brake execution motor successfully reaches the reverse limit position, and if so, execute the next step;

[0131] Forward rotation module 24: used to control the brake actuator motor to rotate forward according to a set mode until the friction plate contacts the brake disc surface;

[0132] The third acquisition module 25 is used to acquire the cumulative positive rotation angle of the brake execution motor, and calculate the current axial position of the friction plate according to the cumulative positive rotation angle and the axial displacement formula; the axial position formula is: S=k*α, where S is the current axial position, k is the axial displacement corresponding to the motor rotation unit angle, and α is the cumulative positive rotation angle;

[0133] The wear amount determination module 26 is used to calculate the wear amount of the corresponding friction plate according to the current axial position and the initial axial position.

[0134] The embodiment of the present invention calculates the wear of the friction plate by measuring the change in the total motor rotation angle from the start of the movement of the actuator motor from the reverse limit to the end of the contact with the brake disc. After every 1,500 kilometers of driving, turn off the ignition switch after parking on a horizontal road, and then independently control the front and rear wheel motors to perform corresponding wear detection; first, through the preset speed control algorithm in the EMB system electronic control unit ECU, use the S-shaped control method for acceleration and the reverse S-shaped control method for deceleration to release the rear wheel motor to the reverse limit, and then use the same control algorithm to clamp the rear wheel motor until it contacts the brake disc, and then release the clamped front wheel motor with the same control method. Before the motor is released, the other side motor needs to be clamped again to ensure parking reliability, and the total motor rotation angle when the four wheels are clamped is recorded respectively. The axial displacement of the friction plate is calculated according to the total motor rotation angle when the four wheels are clamped, and the friction plate wear is calculated by comparing it with the axial displacement of the friction plate during the initial measurement. The friction plate wear measurement method in the embodiment of the present invention determines the displacement of the motor in the axial position by obtaining the rotation angle of the brake actuator motor, thereby realizing accurate detection of the friction plate wear.

[0135] Embodiment 4

[0136] See also Fig. 9 , Fig. 9 Schematic diagram of the structure of an electronic device disclosed in an embodiment of the present invention. The electronic device may be a computer, a server, etc. Of course, in certain circumstances, it may also be a smart device such as a mobile phone, a tablet computer, a monitoring terminal, and an image acquisition device with processing functions. Fig. 9 As shown, the electronic device may include:

[0137] A memory 510 storing executable program codes;

[0138] a processor 520 coupled to the memory 510;

[0139] The processor 520 calls the executable program code stored in the memory 510 to execute part or all of the steps in the friction plate wear measurement method in the first embodiment.

[0140] An embodiment of the present invention discloses a computer-readable storage medium storing a computer program, wherein the computer program enables a computer to execute part or all of the steps in the friction plate wear measurement method in the first embodiment.

[0141] The embodiment of the present invention further discloses a computer program product, wherein when the computer program product is run on a computer, the computer is enabled to execute part or all of the steps in the friction plate wear measurement method in the first embodiment.

[0142] An embodiment of the present invention further discloses an application publishing platform, wherein the application publishing platform is used to publish a computer program product, wherein when the computer program product runs on a computer, the computer executes part or all of the steps in the friction plate wear measurement method in embodiment one.

[0143] In various embodiments of the present invention, it should be understood that the size of the serial numbers of the processes does not necessarily mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0144] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, i.e., they may be located in one place or distributed over multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0145] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0146] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-accessible memory. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product, which is stored in a memory and includes several requests for a computer device (which can be a personal computer, a server or a network device, etc., specifically a processor in a computer device) to perform some or all of the steps of the method described in each embodiment of the present invention.

[0147] In the embodiments provided by the present invention, it should be understood that "B corresponding to A" means that B is associated with A, and B can be determined according to A. However, it should also be understood that determining B according to A does not mean determining B only according to A, and B can also be determined according to A and / or other information.

[0148] A person of ordinary skill in the art can understand that some or all of the steps in the various methods of the embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium, and the storage medium includes a read-only memory (ROM), a random access memory (RAM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), a one-time programmable read-only memory (OTPROM), an electronically erasable rewritable read-only memory (EEPROM), a compact disc (CD-ROM) or other optical disc storage, magnetic disk storage, magnetic tape storage, or any other computer-readable medium that can be used to carry or store data.

[0149] The friction plate wear measurement method, device, electronic device and storage medium disclosed in the embodiments of the present invention are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for general technical personnel in this field, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A method for measuring friction plate wear, characterized in that: include: Acquiring vehicle status information in a parking state, and matching the vehicle status information with a preset judgment logic to determine whether to enter a wear measurement step; After entering the wear measurement step, controlling the brake actuator motor to rotate in the reverse direction according to a set mode until the brake actuator motor reaches a reverse limit position; Obtaining a first cumulative reverse rotation angle of the brake actuator motor, and comparing the first cumulative reverse rotation angle with the second cumulative reverse rotation angle measured last time to determine whether the brake actuator motor successfully reaches the reverse limit position, and if so, executing the next step; The current axial position of the friction plate is calculated according to the first accumulated reverse rotation angle and the axial displacement formula, wherein the axial position formula is: S=k*α, wherein S is the current axial position, k is the axial displacement corresponding to the unit angle of rotation of the motor, and α is the first accumulated reverse rotation angle; The wear amount of the corresponding friction plate is calculated according to the current axial position and the initial axial position.

2. A friction plate wear measurement method, characterized in that: include: Acquiring vehicle status information in a parking state, and matching the vehicle status information with a preset judgment logic to determine whether to enter a wear measurement step; After entering the wear measurement step, controlling the brake actuator motor to rotate in the reverse direction according to a set mode until the brake actuator motor reaches a reverse limit position; Obtaining a first cumulative reverse rotation angle of the brake actuator motor, and comparing the first cumulative reverse rotation angle with the second cumulative reverse rotation angle measured last time to determine whether the brake actuator motor successfully reaches the reverse limit position, and if so, executing the next step; Control the brake actuator motor to rotate in the forward direction according to the set mode until the friction plate contacts the brake disc surface; The accumulated positive rotation angle of the brake actuator motor is obtained, and the current axial position of the friction plate is calculated according to the accumulated positive rotation angle and the axial displacement formula; the axial position formula is: S=k*α, where S is the current axial position, k is the axial displacement corresponding to the unit angle of motor rotation, and α is the accumulated positive rotation angle; The wear amount of the corresponding friction plate is calculated according to the current axial position and the initial axial position.

3. The friction plate wear measurement method according to claim 1, characterized in that: After entering the wear measurement step, controlling the brake actuator motor to rotate in the reverse direction according to a set mode until the brake actuator motor reaches a reverse limit position includes: After entering the wear measurement step, the front wheel brake actuator motor is controlled to rotate forward to perform a re-clamping operation, and the rear wheel brake actuator motor is controlled to rotate reversely according to a set mode until the rear wheel brake actuator motor reaches a reverse limit position.

4. The friction plate wear measurement method according to claim 1, characterized in that: After calculating the wear amount of the corresponding friction plate according to the current axial position and the initial axial position, the method further includes: The current axial position, the accumulated reverse rotation angle and the current mileage are stored in a storage module.

5. The friction plate wear measurement method according to claim 1, characterized in that: The vehicle status information includes ignition key status, vehicle speed, gear status, longitudinal acceleration, lateral acceleration, current mileage, and parking status; The step of matching the vehicle status information with a preset judgment logic to determine whether to enter the wear measurement step includes: When the ignition key is off, the vehicle speed is zero, the gear is in the parking gear, the longitudinal acceleration and the lateral acceleration are both less than the first set threshold, and the difference between the current mileage and the mileage last measured is greater than the second set threshold, the control enters the wear measurement step.

6. The friction plate wear measurement method according to claim 1, characterized in that: The controlling the brake actuator motor to rotate in the reverse direction according to a set mode until the brake actuator motor reaches a reverse limit position includes: Controlling the brake execution motor to enter a first acceleration state, a second acceleration state, and a third acceleration state respectively to control the brake execution motor to perform a rotation acceleration process until the speed of the brake execution motor reaches a first set speed; Controlling the brake actuator motor to enter a uniform speed running state, in which the brake actuator motor runs at a first set speed for a set time; Controlling the brake execution motor to enter a first deceleration state, a second deceleration state, and a third deceleration state respectively to control the brake execution motor to perform a rotation deceleration process until the rotation speed of the brake execution motor reaches a second set rotation speed; When it is detected that the brake actuating motor stops rotating, it is determined that the brake actuating motor reaches a reverse limit position; The controlling the brake actuator motor to rotate in the forward direction according to the set mode until the friction plate contacts the disc surface of the brake disc comprises: Controlling the brake execution motor to enter a fourth acceleration state, a fifth acceleration state, and a sixth acceleration state respectively to control the brake execution motor to perform a rotation acceleration process until the speed of the brake execution motor reaches a third set speed; Controlling the brake actuator motor to enter a uniform speed running state, in which the brake actuator motor runs at a third set speed for a set time; Controlling the brake execution motor to enter a fourth deceleration state, a fifth deceleration state, and a sixth deceleration state respectively to control the brake execution motor to perform a rotation deceleration process until the rotation speed of the brake execution motor reaches a second set rotation speed; When it is detected that the current sensor and / or the rotation acceleration disposed at the brake actuating motor meets the set conditions, it is determined that the friction plate contacts the disc surface of the brake disc.

7. The friction plate wear measurement method according to claim 1, characterized in that: After calculating the wear amount of the corresponding friction plate according to the current axial position and the initial axial position, the method further includes: Data matching is performed based on the wear amount of the friction plate and a preset wear-stiffness mapping table to determine the stiffness data of the current friction plate.

8. A method for measuring friction plate wear, characterized in that: include: A first acquisition module: used for acquiring vehicle status information in a parking state, and matching the vehicle status information with a preset judgment logic to determine whether to enter a wear measurement step; Reverse rotation module: used for controlling the brake actuator motor to rotate in the reverse direction according to a set mode until the brake actuator motor reaches a reverse limit position after entering the wear measurement step; The second acquisition module is used to acquire the first cumulative reverse rotation angle of the brake execution motor, and compare the first cumulative reverse rotation angle with the second cumulative reverse rotation angle measured last time to determine whether the brake execution motor successfully reaches the reverse limit position, and if so, execute the next step; Forward rotation module: used to control the brake actuator motor to rotate forward according to the set mode until the friction plate contacts the brake disc surface; The third acquisition module is used to obtain the cumulative positive rotation angle of the brake execution motor, and calculate the current axial position of the friction plate according to the cumulative positive rotation angle and the axial displacement formula; the axial position formula is: S = k*α, where S is the current axial position, k is the axial displacement corresponding to the unit angle of motor rotation, and α is the cumulative positive rotation angle; Wear amount determination module: used for calculating the wear amount of the corresponding friction plate according to the current axial position and the initial axial position.

9. An electronic device, characterized in that: include: A memory storing executable program code; a processor coupled to the memory; The processor calls the executable program code stored in the memory to execute the friction plate wear measurement method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, wherein the computer program enables a computer to execute the friction lining wear measurement method according to any one of claims 1 to 7.

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