A method and device for estimating brake pad wear of an electro-hydraulic brake system

Abstract

The present invention discloses a brake pad wear estimation method, device, equipment, and storage medium for an electro-hydraulic brake system, belonging to the field of automobile fault diagnosis technology. The method comprises: after installing a new brake pad, collecting data such as braking time, braking pressure, and braking distance during vehicle operation, inputting these data into a brake pad wear estimation model, and calculating the maximum wear coefficient; then inputting this data into the remaining driving distance of the brake pad. S The prediction model calculates the remaining driving distance; the wear coefficient is calculated during the driving process of the car K ,when K >0.9 Kmax , it is determined that the brake pads need to be replaced and a message is pushed to the owner. The present invention can accurately estimate the wear of the brake pads and the remaining driving distance, and accurately remind the owner to replace the brake pads.

Description

Technical Field

[0001] The present invention belongs to the technical field of automobile fault diagnosis, and in particular relates to a method, device, equipment and storage medium for estimating brake pad wear of an electro-hydraulic brake system. Background Art

[0002] Most current vehicles utilize electro-hydraulic braking systems, which apply the brakes. Compared to traditional mechanical brakes, hydraulic braking offers advantages such as fewer failures, less mechanical force loss, faster transmission, and superior braking performance. However, electro-hydraulic braking systems also require timely replacement of worn brake pads to ensure driving safety.

[0003] Brake pad replacement and maintenance are typically performed based on meter readings of mileage and maintenance schedules, with reminders for maintenance or replacement due dates being issued on a first-come, first-served basis. However, in practice, 4S dealerships and repair shops face significant challenges maintaining customer maintenance schedules. Currently, 4S dealerships and repair shops use the scheduled maintenance schedule to roughly estimate whether a vehicle requires maintenance, then have customer service staff call customers based on this rough estimate to remind them to return. However, these maintenance reminders are often inaccurate. Often, vehicles have not reached the required mileage, resulting in premature brake pad replacements that increase costs for owners and create a certain amount of waste.

[0004] In view of the above situation, how to accurately estimate the wear of the brake pads and the remaining driving distance and provide car owners with accurate maintenance time is a technical problem that needs to be solved urgently. Summary of the Invention

[0005] To solve the above technical problems, the present invention provides a method and device, equipment and storage medium for estimating brake pad wear in an electro-hydraulic brake system, which can accurately estimate the brake pad wear and the remaining driving distance, and accurately remind the replacement and maintenance of automobile brake pads.

[0006] In a first aspect, the present invention provides a method for estimating brake pad wear of an electro-hydraulic brake system, comprising the following steps:

[0007] (1) After the new brake pad is installed, the current mileage S0 of the vehicle ECU is obtained and the initial effective thickness l0 of the brake pad is measured; based on the vehicle braking data, it is determined whether the vehicle is unloaded or lightly loaded;

[0008] (2) If it is determined that the vehicle is unloaded or lightly loaded, then obtain braking data under three sets of initial speeds, including braking distance L, braking pressure P, and braking time T. The three sets of initial speeds are a first speed V1, a second speed V2, and a third speed V3, and V1>V2>V3;

[0009] (3) Substitute the three sets of brake data in step (2) into the brake pad wear estimation model, take the average, and calculate the initial value K0 of the brake pad wear coefficient;

[0010] (4) After the car has traveled X1 kilometers, repeat steps (2) and (3) to estimate the current brake pad wear coefficient value K1, and at the same time measure the current effective thickness l1 of the brake pad, and calculate the brake pad wear thickness Δl1 = l0 - l1, and estimate the maximum brake pad wear coefficient Kmax = K1*l0 / Δl1;

[0011] (5) When the car continues to travel X2 kilometers, repeat steps (2) and (3) to estimate the current brake pad wear coefficient value K2, and at the same time measure the current effective thickness l2 of the brake pad, and calculate the brake pad wear thickness Δl2 = l0-l2, calibrate and correct the estimated maximum brake pad wear coefficient Kmax = K2*l0 / Δl2,

[0012] (6) Substitute the calculated data into the prediction model of the remaining travel distance S of the brake pad to calculate the remaining travel distance S;

[0013] (7) While the car is driving, repeat steps (2) and (3) to calculate the brake pad wear coefficient K. When K>0.9Kmax, it is determined that the brake pad needs to be replaced and a message is pushed to the car owner.

[0014] In a further technical solution, in step (3), the brake pad wear estimation model is:

[0015]

[0016] Where K is the brake pad wear coefficient, L is the braking distance, P is the braking pressure, and V is the initial braking speed. The calculation method for the initial value K0 of the brake pad wear coefficient is:

[0017]

[0018] K0=(K01+K02+K03) / 3.

[0019] According to a further technical solution, in the step (2), the braking data of the first speed V1, the second speed V2 and the third speed V3 are respectively: (L1, P1, T1), (L2, P2, T2), (L3, P3, T3).

[0020] A further technical solution is that in step (4), after the new brake pad of the car has traveled X1 kilometers, three sets of braking data at three initial speeds (first speed V1, second speed V2 and third speed V3) when empty or lightly loaded are: (L4, P4, T4), (L5, P5, T5), (L6, P6, T6);

[0021] The calculation method of brake pad wear coefficient value K1 is:

[0022]

[0023] K1=(K11+K12+K13) / 3;

[0024] In step (5), after the new brake pads of the car have traveled X2 kilometers, three sets of braking data at three initial speeds (first speed V1, second speed V2 and third speed V3) when the car is unloaded or lightly loaded: (L7, P7, T7), (L8, P8, T8), (L9, P9, T9);

[0025] The calculation method of brake pad wear coefficient value K2 is:

[0026]

[0027] K2=(K21+K22+K23) / 3.

[0028] According to a further technical solution, the prediction model of the remaining travel distance S of the brake pad is:

[0029]

[0030] A further technical solution is that the method for determining whether the vehicle is empty or lightly loaded is as follows:

[0031] 1) Obtain three sets of braking data (L01, P01, T01), (L02, P02, T02), and (L03, P03, T03) at three vehicle speeds (first speed V1, second speed V2, and third speed V3) when the vehicle is lightly loaded or unloaded;

[0032] 2) Calculate the mass coefficient M0 of the vehicle when it is empty or lightly loaded, and store it in the memory of the lower computer. The calculation model of the mass coefficient M0 is:

[0033]

[0034] M0=(M01+M02+M03) / 3;

[0035] 3) Obtain the braking data (L, P, T) at the current vehicle speed V and calculate the current vehicle mass coefficient M:

[0036]

[0037] 4) When M<1.2M0, the vehicle is judged to be empty or lightly loaded.

[0038] According to a further technical solution, X1 is 10,000 kilometers and X2 is 10,000 kilometers. The brake pad data and the vehicle brake data can be obtained through the OBDII interface.

[0039] In a second aspect, the present invention provides a brake pad wear estimation device for an electro-hydraulic brake system, comprising:

[0040] The communication module obtains the data stream of brake pad data and vehicle braking data and transmits it to the signal processing module; the signal processing module processes the data stream of brake pad data and vehicle braking data and the waveform data of the sensor, obtains the specific values ​​of pressure, speed and distance, and transmits them to the MCU calculation module.

[0041] The MCU calculation module calculates the brake pad wear coefficient using a brake pad wear estimation model based on the brake pad data and the vehicle braking data, and calculates the brake pad remaining driving distance S using a brake pad remaining driving distance S prediction model;

[0042] The reminder module compares the current wear coefficient of the vehicle with the maximum wear coefficient of the vehicle and sends the comparison result to the terminal or diagnostic instrument.

[0043] In a third aspect, the present invention provides a device for estimating brake pad wear of an electro-hydraulic brake system, the device comprising: a memory, a processor, and a computer program stored on the memory and executable on the processor, the computer program being configured to implement the steps of the method for estimating brake pad wear of an electro-hydraulic brake system as described above.

[0044] In a fourth aspect, the present invention provides a storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method for estimating brake pad wear of an electro-hydraulic brake system as described above.

[0045] Beneficial effects

[0046] 1. The brake pad wear estimation method of the electro-hydraulic brake system of the present invention can be detected at any time while the vehicle is running, without the need to go to a 4S / repair shop for detection, with low cost and high detection efficiency.

[0047] 2. The present invention can prompt and alarm for abnormal wear of commercial vehicle brake pads, and can upload data to a terminal in real time as needed, such as an enterprise's vehicle diagnostic management platform. The enterprise diagnostic management platform can also query the vehicle's operating status, thereby enabling the enterprise to monitor the operating data of its commercial vehicles in real time. It can not only detect the wear of the vehicle's brake pads, but also detect operating data such as vehicle speed and position and diagnostic data such as engine status, greatly improving the vehicle safety operation management level of logistics companies.

[0048] 3. The brake pad wear estimation model of the present invention utilizes dynamic principles to establish a brake pad wear coefficient model and a vehicle mass model by collecting real-time kinematic data during vehicle braking. This allows for real-time online estimation of brake pad wear and vehicle load, resulting in high detection efficiency and data accuracy. The present estimation method is simple: after replacing the brake pads, only three acceleration data points are collected from the vehicle when it is unloaded or lightly loaded. This serves as model training data, allowing automatic brake pad wear estimation during daily use.

[0049] 4. The present invention uses random sampling to determine threshold alarm parameters, which is sensitive to data and helps improve the accuracy of data judgment. The computational model of the present invention uses two sets of data of different quality in an interleaved manner, making the data correlation weaker and improving the accuracy of the solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 A flowchart of brake pad wear estimation for an electro-hydraulic brake system according to an embodiment of the present invention;

[0051] Figure 2 This is a structural diagram of a brake pad wear estimation device for an electro-hydraulic brake system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0052] In order to help those skilled in the art better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. 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 those skilled in the art without creative work are within the scope of protection of this application.

[0053] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0054] Example 1

[0055] like Figure 1 As shown, a method for estimating brake pad wear of an electro-hydraulic brake system includes the following steps:

[0056] (1) After the new brake pad is installed, the current mileage S0 of the vehicle ECU is obtained and the initial effective thickness l0 of the brake pad is measured; based on the vehicle braking data, it is determined whether the vehicle is unloaded or lightly loaded;

[0057] (2) If it is determined that the vehicle is unloaded or lightly loaded, then obtain braking data under three sets of initial speeds, including braking distance L, braking pressure P, and braking time T. The three sets of initial speeds are a first speed V1, a second speed V2, and a third speed V3, and V1>V2>V3;

[0058] The braking data of the first speed V1, the second speed V2 and the third speed V3 are respectively: (L1, P1, T1), (L2, P2, T2), (L3, P3, T3);

[0059] (3) Substitute the three sets of brake data in step (2) into the brake pad wear estimation model, take the average, and calculate the initial value K0 of the brake pad wear coefficient;

[0060] The brake pad wear estimation model is:

[0061]

[0062] Where K is the brake pad wear coefficient, L is the braking distance, P is the braking pressure, and V is the initial braking speed. The calculation process of the initial value K0 of the brake pad wear coefficient is as follows:

[0063]

[0064] K0=(K01+K02+K03) / 3.

[0065] (4) After the car has traveled X1 kilometers, repeat steps (2) and (3) to estimate the current brake pad wear coefficient value K1, and at the same time measure the current effective thickness l1 of the brake pad, and calculate the brake pad wear thickness Δl1 = l0 - l1, and estimate the maximum brake pad wear coefficient Kmax = K1*l0 / Δl1;

[0066] The brake pad wear coefficient K1 is calculated as follows: After a new brake pad has traveled X1 kilometers, three sets of braking data are collected at three initial speeds (first speed V1, second speed V2, and third speed V3) when the vehicle is unloaded or lightly loaded: (L4, P4, T4), (L5, P5, T5), and (L6, P6, T6). These data are input into the brake pad wear estimation model and the average is taken. The specific calculation process is as follows:

[0067]

[0068] K1=(K11+K12+K13) / 3.

[0069] (5) After the car continues to travel X2 kilometers, repeat steps (2) and (3) to estimate the current brake pad wear coefficient value K2. At the same time, measure the current effective thickness l2 of the brake pad and calculate the brake pad wear thickness Δl2 = l0 - l2. Calibrate and correct the estimated maximum brake pad wear coefficient Kmax = K2*l0 / Δl2.

[0070] The brake pad wear coefficient K2 is calculated as follows: After a new brake pad has traveled X2 kilometers, three sets of braking data are collected at three initial speeds (first speed V1, second speed V2, and third speed V3) when the vehicle is unloaded or lightly loaded: (L7, P7, T7), (L8, P8, T8), and (L9, P9, T9). These data are input into the brake pad wear estimation model and the average is taken. The specific calculation process is as follows:

[0071]

[0072] K2=(K21+K22+K23) / 3.

[0073] (6) Substitute the calculated data into the prediction model of the remaining travel distance S of the brake pad: Calculate the remaining driving distance S;

[0074] (7) While the car is driving, repeat steps (2) and (3) to calculate the brake pad wear coefficient K. When K>0.9Kmax, it is determined that the brake pad needs to be replaced and a message is pushed to the car owner.

[0075] The method for determining whether the vehicle is empty or lightly loaded is as follows:

[0076] 1) Obtain three sets of braking data (L01, P01, T01), (L02, P02, T02), and (L03, P03, T03) at three vehicle speeds (first speed V1, second speed V2, and third speed V3) when the vehicle is lightly loaded or unloaded;

[0077] 2) Calculate the mass coefficient M0 of the vehicle when it is empty or lightly loaded, and store it in the memory of the lower computer. The calculation model of the mass coefficient M0 is:

[0078]

[0079] M0=(M01+M02+M03) / 3;

[0080] 3) Obtain the braking data (L, P, T) at the current vehicle speed V and calculate the current vehicle mass coefficient M:

[0081]

[0082] 4) When M<1.2M0, the vehicle is judged to be empty or lightly loaded.

[0083] The X1 is 10,000 kilometers, and the X2 is 10,000 kilometers. The brake pad data and vehicle brake data can be obtained through the OBDII interface.

[0084] Example 2

[0085] like Figure 2 As shown, a brake pad wear estimation device for an electro-hydraulic brake system includes:

[0086] The communication module obtains the data stream of brake pad data and vehicle braking data and transmits it to the signal processing module; the signal processing module processes the data stream of brake pad data and vehicle braking data and the waveform data of the sensor, obtains the specific values ​​of pressure, speed and distance, and transmits them to the MCU calculation module.

[0087] The MCU calculation module calculates the brake pad wear coefficient using a brake pad wear estimation model based on the brake pad data and the vehicle braking data, and calculates the brake pad remaining driving distance S using a brake pad remaining driving distance S prediction model;

[0088] The reminder module compares the vehicle's current wear coefficient with the vehicle's maximum wear coefficient and sends the comparison result to a terminal or diagnostic instrument. The comparison result can be pushed to a terminal such as the vehicle owner's terminal or other management platform via the 4G / 5G communication module, or pushed to a diagnostic instrument for display via serial communication.

[0089] Example 3

[0090] A device for estimating brake pad wear of an electro-hydraulic brake system includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the method of embodiment 1.

[0091] It should be understood that in this embodiment, the memory may include a read-only memory and a random access memory, and provide instructions and data to the processor. A portion of the memory may also include a non-volatile random access memory. For example, the memory may also store device type information.

[0092] The processor may be a central processing unit (CPU), or other general-purpose processors, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), an off-the-shelf field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. A general-purpose processor may be a microprocessor or any conventional processor.

[0093] Computer programs (also called programs, software, software applications, or code) include machine instructions for a programmable processor and may be implemented using high-level procedural and / or object-oriented programming languages, and / or assembly / machine languages.

[0094] During implementation, each step of the above method may be completed by an integrated logic circuit of hardware in a processor or by instructions in the form of software.

[0095] The method in Example 1 can be directly implemented as execution by a hardware processor, or can be executed by a combination of hardware and software modules in the processor. The software module can be located in a storage medium mature in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, etc.

[0096] Example 4

[0097] A storage medium stores a computer program, which implements the method of embodiment 1 when executed by a processor.

[0098] Storage media include: USB flash drives, mobile hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks or optical disks, and other media that can store program codes.

[0099] Those skilled in the art will appreciate that the methods described in conjunction with the various examples of this embodiment can be implemented using electronic hardware or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0100] The above specific embodiments do not constitute a limitation on the scope of protection of this application. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application shall be included within the scope of protection of this application.

Claims

1. A method for estimating brake pad wear in an electro-hydraulic brake system, characterized in that: The following steps are involved: (1) After installing the new brake pad, obtain the current mileage S0 from the vehicle ECU and measure the initial effective thickness of the brake pad l0 ; Determine whether the vehicle is unloaded or lightly loaded based on the vehicle braking data; (2) If it is determined that the vehicle is unloaded or lightly loaded, the braking data under three sets of initial speeds are obtained, including: braking distance L, braking pressure P, and braking time T. The three sets of initial speeds are a first speed V1, a second speed V2, and a third speed V3, and V1>V2>V3; (3) Substitute the three sets of brake data in step (2) into the brake pad wear estimation model, take the average, and calculate the initial value of the brake pad wear coefficient K0 ; (4) After the car has traveled X1 kilometers, repeat steps (2) and (3) to estimate the current brake pad wear coefficient value. K1 , and measure the current effective thickness of the brake pad at the same time l1, And calculate the brake pad wear thickness Δl1= l0- l1 , estimate the maximum wear coefficient of the brake pad Kmax = K1 * l0 / Δl1 ; (5) When the car continues to travel X2 kilometers, repeat steps (2) and (3) to estimate the current brake pad wear coefficient value K2 , and measure the current effective thickness of the brake pad at the same time l2, And calculate the brake pad wear thickness Δl2= l0- l2 , calibrate and correct the estimated maximum wear coefficient of the brake pad Kmax = K2 * l0 / Δl2 , (6) Substitute the calculated data into the remaining travel distance of the brake pad S The prediction model is used to calculate the remaining driving distance S; (7) While the car is driving, repeat steps (2) and (3) to calculate the brake pad wear coefficient. K ,when K >0.9 Kmax , it determines that the brake pads need to be replaced and pushes the message to the owner; In step (3), the brake pad wear estimation model is: ， in, K is the brake pad wear coefficient, L is the braking distance, P is the brake pressure, V is the initial braking speed; Initial value of brake pad wear coefficient K0 The calculation method is: ， ， ， K0=(K01+K02+K03) / 3; In step (4), after the new brake pads of the car have traveled X1 kilometers, the three sets of braking data at the first speed V1, the second speed V2 and the third speed V3 when the car is unloaded or lightly loaded are: L4,P4,T4 ]、[ L5,P5,T5 ]、[ L6,P6,T6 ]; The calculation method of brake pad wear coefficient value K1 is: ， ， ， K1=(K11+K12+K13) / 3; In step (5), after the new brake pads of the car have traveled X2 kilometers, the three sets of braking data at the first speed V1, the second speed V2 and the third speed V3 when the car is unloaded or lightly loaded are: L7,P7,T7 ]、[ L8,P8,T8 ]、[ L9,P9,T9 ]; The calculation method of brake pad wear coefficient value K2 is: ， ， ， K2=(K21+K22+K23) / 3; Remaining travel distance of brake pads S The prediction model is: 。 2. The method for estimating brake pad wear of an electro-hydraulic brake system according to claim 1, characterized in that: In the step (2), the braking data of the first speed V1, the second speed V2 and the third speed V3 are respectively: L1,P1,T1 ]、[ L2, P2,T2 ]、[ L3,P3,T3 ].

3. The method for estimating brake pad wear of an electro-hydraulic brake system according to claim 1, characterized in that: The method for determining whether the vehicle is empty or lightly loaded is as follows: 1) Obtain three sets of braking data at the first speed V1, the second speed V2 and the third speed V3 when the vehicle is lightly loaded or unloaded. L01,P01,T01 ]、[ L02,P02,T02 ]、[ L03,P03,T03 ]; 2) Calculate the mass coefficient of the vehicle when it is empty or lightly loaded M0 , and stored in the lower computer memory, where the quality coefficient M0 Computational model: , , ， M0=(M01+M02+M03) / 3 ； 3) Get the braking data at the current vehicle speed V [ L,P,T ], calculate the current vehicle mass coefficient M: ， 4) When M <1.2 M0 , it is determined that the current vehicle is empty or lightly loaded.

4. The method for estimating brake pad wear of an electro-hydraulic brake system according to claim 1, wherein: The X1 is 10,000 kilometers and the X2 is 10,000 kilometers.

5. An estimation device for the brake pad wear estimation method of an electro-hydraulic brake system according to claim 1, characterized in that: include: The communication module obtains the data stream of the brake pad data and the vehicle braking data and transmits it to the signal processing module; The signal processing module processes the data stream of brake pad data, vehicle braking data, and sensor waveform data to obtain specific values ​​of pressure, speed, and distance, and transmits them to the MCU calculation module; The MCU calculation module calculates the brake pad wear coefficient and the remaining driving distance of the brake pad through the brake pad wear estimation model based on the brake pad data and the vehicle braking data. S The prediction model calculates the remaining driving distance of the brake pad S ; The reminder module compares the current wear coefficient of the vehicle with the maximum wear coefficient of the vehicle and sends the comparison result to the terminal or diagnostic instrument.

6. A brake pad wear estimation device for an electro-hydraulic brake system, characterized in that: The device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the method for estimating brake pad wear of an electro-hydraulic brake system according to any one of claims 1 to 4.

7. A storage medium, characterized in that: The storage medium stores a computer program, which, when executed by a processor, implements the brake pad wear estimation method according to any one of claims 1 to 4.

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