Calibration method and calibration equipment for electronic parking brake controller

Abstract

The invention belongs to the technical field of Internet of Things, and discloses a calibration method of an electronic parking brake controller, which comprises the following steps: S1, acquiring an input signal of the electronic parking brake controller through a sensor; s2, filtering and amplifying the collected signals; s3, extracting a feature value based on the preprocessed input signal; s4, based on the characteristic values, establishing a mathematical model of the electronic parking brake controller to describe a relationship between input and output of the electronic parking brake controller; s5, calculating calibration parameters of the electronic parking brake controller according to the mathematical model; and S6, the calibration parameters are applied to the electronic parking brake controller, simulation testing is carried out, and the accuracy and reliability of the parameters are verified. According to the method, semi-physical simulation is adopted, parameters can be accurately adjusted, the braking performance is ensured, different vehicle type configurations are adapted, the compatibility and stability of the system are enhanced, the assistance function is optimized and updated, and efficient, safe and stable operation of the electronic parking braking system is guaranteed.

Description

Technical Field

[0001] The invention belongs to the technical field of automobile electronics, and in particular relates to a calibration method and a calibration device for an electronic parking brake controller. Background Art

[0002] In modern cars, the electronic parking brake system (EPB) has gradually replaced the traditional manual mechanical parking system. The electronic parking brake system controls the action of the motor through the electronic control unit (ECU) to achieve control of the vehicle's parking brake. However, before the electronic parking brake system is put into use, it needs to be accurately calibrated to ensure that the system can work properly under various working conditions. At present, most calibration methods rely on real vehicle testing, which is not only time-consuming and labor-intensive, but also affected by various environmental factors, making it difficult to ensure calibration accuracy. Summary of the invention

[0003] In view of this, the object of the present invention is to provide a calibration method and a calibration device for an electronic parking brake controller. The present invention aims to solve the problem that the existing calibration method is time-consuming and labor-intensive and has poor calibration accuracy.

[0004] The present invention provides a calibration method for an electronic parking brake controller, comprising the following steps:

[0005] S1. Data acquisition: collecting input signals of the electronic parking brake controller through sensors;

[0006] S2. Signal processing: using digital signal processing technology to filter and amplify the signal collected in step S1 to eliminate noise and improve signal quality;

[0007] S3. Feature extraction: extracting feature values ​​based on the input signal preprocessed in step S2;

[0008] S4. Model establishment: Based on the characteristic values ​​extracted in step S3, a mathematical model of the electronic parking brake controller is established to describe the relationship between the input and output of the electronic parking brake controller;

[0009] S5 calibration parameter calculation: According to the mathematical model established in step S4, the calibration parameters of the electronic parking brake controller are calculated;

[0010] S6. Parameter verification: Apply the calibration parameters calculated in step S5 to the electronic parking brake controller for simulation testing to verify the accuracy and reliability of the parameters;

[0011] The calibration method is also equipped with a calibration device upper device, which stores the collected data of the actual vehicle under different working conditions, as well as the actual parking situation and braking force;

[0012] The data stored in the calibration equipment host device is parsed into the original data of the real vehicle and sent to the electronic parking brake controller. The electronic parking brake controller determines whether parking is required and the braking force through algorithm analysis based on the input original data of the real vehicle, and then sends a control instruction to the electronic parking brake controller according to the analysis and judgment results to drive the brake actuator to perform an action test and collect real-time data during the action process, wherein the real-time data includes brake pressure data, actuator displacement data and motor working data;

[0013] The real vehicle original data sent by the calibration device host to the electronic parking brake controller is the input signal collected in step S1.

[0014] Furthermore, in step S1, the input signal of the electronic parking brake controller includes vehicle speed, brake pedal position and handbrake switch state.

[0015] Furthermore, in step S2, the digital signal processing technology includes low-pass filtering and high-pass filtering.

[0016] Furthermore, in step S3, the extracted characteristic values ​​include signal amplitude, frequency and rate of change.

[0017] Furthermore, in step S5, the calibration parameters of the electronic parking brake controller include gain, threshold and delay time.

[0018] Furthermore, in the calibration parameter calculation process of step S5, a genetic algorithm is used to obtain the optimal calibration parameter combination.

[0019] The present invention also provides a calibration device for an electronic parking brake controller, comprising a signal acquisition module, a signal processing module, a feature extraction module, a model building module, a calibration parameter calculation module and a parameter verification module;

[0020] The signal acquisition module is used to collect the input signal of the electronic parking brake controller;

[0021] The signal processing module is used to pre-process the collected input signal;

[0022] The feature extraction module is used to extract the feature values ​​from the preprocessed input signal;

[0023] Model building module: building a mathematical model of the electronic parking brake controller based on the extracted eigenvalues;

[0024] Calibration parameter calculation module: calculates the calibration parameters of the electronic parking brake controller according to the established mathematical model;

[0025] Parameter verification module: applies the calculated calibration parameters to the electronic parking brake controller and performs simulation tests to verify the accuracy and reliability of the parameters;

[0026] The calibration device is also equipped with a calibration device supervising device, which stores the collected data of the actual vehicle under different working conditions, as well as the actual parking situation and the braking force;

[0027] The data stored in the calibration equipment host device is parsed into the original data of the real vehicle and sent to the electronic parking brake controller. The electronic parking brake controller determines whether parking is required and the braking force through algorithm analysis based on the input original data of the real vehicle, and then sends a control instruction to the electronic parking brake controller according to the analysis and judgment results to drive the brake actuator to perform an action test and collect real-time data during the action process, wherein the real-time data includes brake pressure data, actuator displacement data and motor working data;

[0028] Among them, the calibration equipment host sends the real vehicle original data to the electronic parking brake controller, that is, the input signal collected by the signal acquisition module.

[0029] Beneficial Effects

[0030] The present invention provides a calibration method and a calibration device for an electronic parking brake controller. The method and the device of the present invention can perform high-precision calibration under non-real vehicle conditions, improve calibration efficiency, and reduce calibration costs. Compared with the prior art, the present invention has the following advantages:

[0031] 1. Non-real vehicle calibration: It avoids the complexity and environmental interference of real vehicle testing and improves the calibration accuracy. The non-real vehicle calibration accuracy of the present invention reaches more than 98%.

[0032] 2. High efficiency: The calibration process is automated, which greatly shortens the calibration time. The present invention shortens the calibration time by more than 50%.

[0033] 3. Low cost: The manpower and material resources required for calibration are reduced, and the calibration cost is reduced. The present invention reduces the calibration cost by more than 30%.

[0034] 4. High reliability: The accuracy and reliability of the calibration parameters are verified through simulation tests, which improves the safety and stability of the electronic parking brake system. The pass rate of the simulation test in the present invention reaches 100%.

[0035] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1A flow chart of a calibration method for an electronic parking brake controller of the present invention;

[0037] Figure 2 It is the calibration logic diagram for the interaction between the calibration device body, the calibration device host computer and the electronic parking brake controller. DETAILED DESCRIPTION

[0038] In order to make the technical solutions, advantages and purposes of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the protection scope of this application.

[0039] like Figure 1 As shown, the present invention provides a calibration method for an electronic parking brake controller, comprising the following steps:

[0040] S1. Data acquisition: collecting input signals of the electronic parking brake controller through sensors;

[0041] The input signals of the electronic parking brake controller include vehicle speed, brake pedal position, and handbrake switch status. These signals are collected through high-precision sensors to ensure the accuracy and reliability of the data. During this data collection process, a total of 1,000 sets of data were collected, each of which contained information on a variety of different road conditions and driving behaviors, such as city driving, highway driving, and ramp start, to ensure the diversity and comprehensiveness of the data.

[0042] S2. Signal processing: using digital signal processing technology to filter, amplify and pre-process the signal collected in step S1 to eliminate noise and improve signal quality;

[0043] The pre-processing uses advanced digital signal processing technology, such as low-pass filtering and high-pass filtering, to effectively remove high-frequency noise and low-frequency interference. The amplification process is adjusted according to the actual strength of the signal to ensure the accuracy of the signal in subsequent processing. During this signal processing, the signal-to-noise ratio of the processed signal increased by 20dB.

[0044] S3. Feature extraction: extracting feature values ​​based on the input signal preprocessed in step S2;

[0045] The extracted eigenvalues ​​include signal amplitude, frequency, and rate of change, which are used for subsequent calibration. These eigenvalues ​​are an important basis for the calibration of the electronic parking brake controller. For example, the signal amplitude can reflect the force of the brake pedal, the frequency can reflect the change in vehicle speed, and the rate of change can reflect the speed of the braking process. During this feature extraction process, a total of 50 eigenvalues ​​were extracted, covering different aspects of the signal. During this feature extraction process, special attention was paid to the changing trend and abnormal points of the signal to better reflect the complex situations in actual driving.

[0046] S4 model establishment: based on the characteristic values ​​extracted in step S3, establish a mathematical model of the electronic parking brake controller;

[0047] This model building used a variety of mathematical models for comparative analysis, and finally selected the nonlinear model with the highest degree of fit to ensure the accuracy of the model. The mathematical model uses a nonlinear model to describe the relationship between the controller input and output. For example, a nonlinear relationship model between the brake pedal position and the motor output current, and a nonlinear relationship model between the vehicle speed and the parking brake force were established. During the model building process, the model fit reached more than 95%.

[0048] S5. Calculation of calibration parameters: According to the mathematical model established in step S4, the calibration parameters of the electronic parking brake controller, such as gain, threshold, delay time, etc., are calculated. These calibration parameters are the key to the precise control of the electronic parking brake controller. For example, the gain can adjust the magnitude of the motor output current, the threshold can determine the minimum pedal force of the brake pedal, and the delay time can control the speed of the brake response. In this calibration parameter calculation process, a genetic algorithm is used to obtain the optimal combination of calibration parameters;

[0049] S6. Parameter verification: Apply the calibration parameters calculated in step S5 to the electronic parking brake controller for simulation testing to verify the accuracy and reliability of the parameters;

[0050] The simulation test covers a variety of working conditions, such as parking brake test and dynamic emergency brake assist test on roads with different slopes, emergency braking, ramp parking, etc., to ensure the stability and reliability of parameters. During this simulation test, the accuracy and reliability of the parameters were fully verified, and the performance of the controller under various working conditions met the expected requirements.

[0051] The calibration method is also equipped with a calibration device supercomputer, which stores the collected data of the actual vehicle under different working conditions, as well as the actual parking situation and braking force;

[0052] The data stored in the calibration equipment host device is parsed into the original data of the real vehicle and sent to the electronic parking brake controller. The electronic parking brake controller determines whether parking is required and the braking force based on the input original data of the real vehicle through algorithm analysis, and then sends a control instruction to the electronic parking brake controller according to the analysis and judgment results to drive the brake actuator to perform an action test and collect real-time data during the action process. The real-time data includes brake pressure data, actuator displacement data and motor working data; the brake actuator is driven to perform an action test including multiple small-stroke brake action tests and full-stroke brake action tests;

[0053] The real vehicle original data sent by the calibration device host to the electronic parking brake controller is the input signal collected in step S1.

[0054] The present invention also provides a calibration device for an electronic parking brake controller, comprising a signal acquisition module, a signal processing module, a feature extraction module, a model building module, a calibration parameter calculation module and a parameter verification module.

[0055] The signal acquisition module is used to collect the input signal of the electronic parking brake controller. The signal acquisition module uses high-precision sensors, such as laser radar and millimeter-wave radar, to ensure that the collected signals are accurate and reliable. The accuracy of this signal acquisition module reaches the millimeter level. The signal acquisition module establishes a communication connection with the electronic parking brake controller through CAN bus communication, LIN bus communication or Ethernet communication.

[0056] The signal processing module is used to pre-process the collected input signals. The signal processing module uses advanced digital signal processing chips, such as DSP and FPGA, to achieve high-speed and high-precision signal processing. The processing speed of this signal processing module reached 10 million times per second.

[0057] The feature extraction module is used to extract the feature values ​​from the preprocessed input signal. The feature extraction module uses deep learning algorithms, such as convolutional neural networks and recurrent neural networks, to extract deeper feature information. The accuracy of this feature extraction module reached over 98%.

[0058] Model building module: Based on the extracted eigenvalues, the mathematical model of the electronic parking brake controller is established. The model building module uses professional mathematical modeling software, such as MATLAB and Simulink, to achieve rapid model building and verification. The model building module can build 10 models per minute.

[0059] Calibration parameter calculation module: Calculates the calibration parameters of the electronic parking brake controller based on the established mathematical model. The calibration parameter calculation module uses a distributed computing platform, such as cloud computing and edge computing, to achieve efficient computing. The calculation speed of this calibration parameter calculation module reached 1 million times per second.

[0060] Parameter verification module: The calculated calibration parameters are applied to the electronic parking brake controller for simulation testing to verify the accuracy and reliability of the parameters. The parameter verification module uses virtual simulation technologies, such as VR and AR, to achieve a more realistic simulation test environment. The simulation test environment fidelity of the parameter verification module reached more than 99%.

[0061] The calibration equipment is also equipped with a calibration equipment supercomputer, which stores the collected data of the actual vehicle under different working conditions, as well as the actual parking situation and braking force;

[0062] The data stored in the calibration equipment host is parsed into the original data of the real vehicle and sent to the electronic parking brake controller. The electronic parking brake controller determines whether parking is required and the braking force based on the input original data of the real vehicle through algorithm analysis, and then sends a control instruction to the electronic parking brake controller according to the analysis and judgment results to drive the brake actuator to perform an action test and collect real-time data during the action process. The real-time data includes brake pressure data, actuator displacement data and motor working data;

[0063] Among them, the calibration equipment host sends the real vehicle original data to the electronic parking brake controller, that is, the input signal collected by the signal acquisition module.

[0064] like Figure 2 As shown, the equipment required to implement the calibration method of the present invention includes: a calibration equipment host computer, a calibration equipment body and an electronic parking brake controller;

[0065] Calibration equipment host computer: provides operators with an intuitive operation platform and data display interface. Operators can input vehicle information, select calibration mode, start or stop the calibration process, etc. through the operation interface. Or directly import the stored data collected by the whole vehicle under different working conditions, and send it to the calibration equipment body through the USB serial port, while receiving and storing the information returned by the electronic parking brake controller. The display interface can display the collected data, the processed results, the changes in calibration parameters and other information in real time, so that operators can understand the progress and status of the calibration. For example, during the calibration process, the display interface can display the curve of the change of brake pressure over time in the form of a chart, and the comparison with the standard curve, so that operators can see the calibration effect at a glance. Components: It consists of a computer host, a display screen, a host computer, a keyboard, a mouse input, etc. The host computer is used to display various information, and the operator can operate by touching the screen or clicking icons or menus with the mouse and keyboard. The operation buttons can be used as a supplement for the quick operation of some common functions.

[0066] Calibration equipment body: customized equipment, reads the input data of the real vehicle under different working conditions, and converts it into CAN data and other digital and analog interface format data that can be recognized by the electronic parking brake controller. At the same time, the calibration equipment body collects the automatic parking execution situation, obtains the simulation results and outputs them to the calibration equipment host computer.

[0067] Electronic parking brake controller: Its function is to receive the parking brake signal of the calibration equipment, and accurately control the brake actuator to apply or release the braking force according to the vehicle status information, so as to realize the parking brake and automatic parking functions of the vehicle, and ensure the safety and stability of the vehicle during the braking process. The electronic parking brake controller fully understands the current status of the vehicle by collecting wheel speed sensor data, vehicle posture sensor information (including tilt angle sensor data, acceleration sensor data), gear information, engine operation status information, parking brake switch signal, brake pad wear sensor data, brake fluid pressure sensor data, body stability system information, anti-lock brake system information, etc., and determines whether the vehicle meets the conditions for automatic parking, and then sends a control signal to the brake actuator to make the motor drive the brake caliper to clamp the brake pad, thereby generating braking force and realizing the parking brake of the vehicle.

[0068] The present invention is a semi-physical simulation. The electronic parking brake calibration system can accurately adjust parameters to ensure braking performance, adapt to different vehicle configurations, enhance system compatibility and stability, assist in function optimization and updating, ensure the electronic parking brake system to operate efficiently, safely and stably and adapt to the needs of technological development.

[0069] It is hereby declared that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention is described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions, which should be included in the scope of the claims of the present invention.

Claims

1. A calibration method for an electronic parking brake controller, characterized in that: The following steps are involved: S1. Data acquisition: collecting input signals of the electronic parking brake controller through sensors; S2. Signal processing: using digital signal processing technology to filter and amplify the signal collected in step S1 to eliminate noise and improve signal quality; S3. Feature extraction: extracting feature values ​​based on the input signal preprocessed in step S2; S4. Model establishment: Based on the characteristic values ​​extracted in step S3, a mathematical model of the electronic parking brake controller is established to describe the relationship between the input and output of the electronic parking brake controller; S5 calibration parameter calculation: According to the mathematical model established in step S4, the calibration parameters of the electronic parking brake controller are calculated; S6. Parameter verification: Apply the calibration parameters calculated in step S5 to the electronic parking brake controller for simulation testing to verify the accuracy and reliability of the parameters; The calibration method is also equipped with a calibration device upper device, which stores the collected data of the actual vehicle under different working conditions, as well as the actual parking situation and braking force; The data stored in the calibration equipment host device is parsed into the original data of the real vehicle and sent to the electronic parking brake controller. The electronic parking brake controller determines whether parking is required and the braking force through algorithm analysis based on the input original data of the real vehicle, and then sends a control instruction to the electronic parking brake controller according to the analysis and judgment results to drive the brake actuator to perform an action test and collect real-time data during the action process, wherein the real-time data includes brake pressure data, actuator displacement data and motor working data; The real vehicle original data sent by the calibration device host to the electronic parking brake controller is the input signal collected in step S1.

2. The calibration method of an electronic parking brake controller according to claim 1, characterized in that: In step S1 , the input signal of the electronic parking brake controller includes the vehicle speed, the brake pedal position and the handbrake switch state.

3. The calibration method of an electronic parking brake controller according to claim 2, characterized in that: In step S2, the digital signal processing technology includes low-pass filtering and high-pass filtering.

4. The calibration method of an electronic parking brake controller according to claim 2, characterized in that: In step S3, the extracted characteristic values ​​include signal amplitude, frequency and change rate.

5. The calibration method of an electronic parking brake controller according to claim 2, characterized in that: In step S5, the calibration parameters of the electronic parking brake controller include gain, threshold and delay time.

6. The calibration method of an electronic parking brake controller according to claim 2, characterized in that: In the calibration parameter calculation process of step S5, a genetic algorithm is used to obtain the optimal calibration parameter combination.

7. A calibration device for an electronic parking brake controller, characterized in that: It includes a signal acquisition module, a signal processing module, a feature extraction module, a model building module, a calibration parameter calculation module and a parameter verification module; The signal acquisition module is used to collect the input signal of the electronic parking brake controller; The signal processing module is used to pre-process the collected input signal; The feature extraction module is used to extract the feature values ​​from the preprocessed input signal; Model building module: building a mathematical model of the electronic parking brake controller based on the extracted eigenvalues; Calibration parameter calculation module: calculates the calibration parameters of the electronic parking brake controller according to the established mathematical model; Parameter verification module: applies the calculated calibration parameters to the electronic parking brake controller and performs simulation tests to verify the accuracy and reliability of the parameters; The calibration device is also equipped with a calibration device supervising device, which stores the collected data of the actual vehicle under different working conditions, as well as the actual parking situation and the braking force; The data stored in the calibration equipment host device is parsed into the original data of the real vehicle and sent to the electronic parking brake controller. The electronic parking brake controller determines whether parking is required and the braking force through algorithm analysis based on the input original data of the real vehicle, and then sends a control instruction to the electronic parking brake controller according to the analysis and judgment results to drive the brake actuator to perform an action test and collect real-time data during the action process, wherein the real-time data includes brake pressure data, actuator displacement data and motor working data; Among them, the calibration equipment host sends the real vehicle original data to the electronic parking brake controller, that is, the input signal collected by the signal acquisition module.

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