A system and method for intelligently identifying vehicle brake vibration

Abstract

The present invention provides a system and method for intelligently identifying vehicle brake jitter, including a wheel speed sensor, an EPS electric power steering controller, an ESC controller, a brake jitter identification button and a brake jitter alarm. The brake jitter identification button is designed by utilizing the vehicle's existing ESC controller, electric power steering controller and wheel speed sensor. The user can select or cancel the function, which is completely updated through the ESC controller and EPS electric power steering controller software logic. There is no need to modify the vehicle chassis and other body parts, and no additional material cost and mold cost. The method for identifying vehicle brake jitter disclosed by the present invention starts from the typical phenomenon of jitter generation, specifically identifies vehicle brake jitter, and promptly feeds back the identification result to the driver, thereby improving driving safety.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle brake jitter recognition, and in particular to a system and method for intelligently recognizing vehicle brake jitter. Background Art

[0002] The development of the automobile industry has made cars enter thousands of households, and the improvement of people's living standards has put forward higher requirements for vehicle driving comfort. The vehicle's NVH (Noise, Vibration and Harshness) performance has become the focus of attention in the vehicle development process.

[0003] During vehicle driving, especially under high-speed braking conditions, jitter is a complex nonlinear dynamic problem, which has always been the focus and difficulty of vehicle research. When the vehicle is driving at high speed and the driver steps on the brake pedal, it is often an emergency condition that requires immediate deceleration. At this time, the vehicle will experience unexpected continuous jitter, which will cause the driver to panic and easily make mistakes, thus seriously affecting driving safety. At the same time, the driving experience of the driver and passengers will also be quite poor.

[0004] The jitter of a vehicle under braking conditions has various causes: it may come from the stimulation of uneven road surfaces; it may come from the mud adhering to the wheels; it may also be caused by the failure of brake parts. Among them, the jitter caused by part failure is continuous and the most harmful. For drivers, there is no effective analysis method to help them determine the cause of brake jitter; the existing method of determining vehicle brake jitter is to store the vehicle at the after-sales maintenance center, and professional engineers will disassemble the parts for flaw detection, and repeated road test simulations are required. This method is relatively complicated for the identification process of vehicle brake jitter, takes a long time and is expensive. Summary of the invention

[0005] The present invention discloses a system and method for intelligently identifying vehicle brake jitter, which solves the problem that the existing method of determining vehicle brake jitter requires the vehicle to be stored in an after-sales maintenance center, and professional engineers to disassemble the parts for flaw detection, and conduct repeated road test simulations, thereby resulting in a complicated, time-consuming and expensive identification process for vehicle brake jitter. Starting from the typical phenomenon caused by vehicle brake jitter, the vehicle's existing ESC controller, electric power steering controller, wheel speed sensor and the like are combined with an algorithm to identify vehicle brake jitter, without the need to modify the vehicle chassis and other parts of the body, and without requiring additional material costs and mold costs.

[0006] To achieve the above object, the technical solution of the present invention is specifically implemented as follows:

[0007] On one hand, the present invention discloses a system for intelligently identifying vehicle brake jitter, comprising a wheel speed sensor, an EPS electric power steering controller, an ESC controller, a brake jitter identification button and a brake jitter alarm, wherein the wheel speed sensor is fixedly arranged on each wheel to collect vehicle speed signals and transmit them to the ESC controller; the EPS electric power steering controller is integrated with a steering wheel torque sensor to monitor the torque of the steering column under the steering wheel and transmit it to the ESC controller through a bus; the ESC controller is integrated with a vehicle master cylinder pressure sensor to receive the vehicle speed signal collected by the wheel speed sensor and the torque signal of the steering column monitored by the steering wheel torque sensor, and when receiving the vehicle speed signal collected by the wheel speed sensor When the vehicle speed signal collected by the wheel speed sensor and the brake pressure signal collected by the vehicle master cylinder pressure sensor reach a preset first threshold, the brake jitter identification module provided in the ESC controller identifies whether the vehicle is in brake jitter. If it is identified as brake jitter, the ESC controller detects and determines whether the vehicle speed signal collected by the wheel speed sensor and the brake pressure signal collected by the vehicle master cylinder pressure sensor reach a preset second threshold and the brake jitter duration is greater than a preset time. When it is determined that the vehicle speed signal collected by the wheel speed sensor and the brake pressure signal collected by the vehicle master cylinder pressure sensor reach the preset second threshold and the brake jitter duration is greater than a preset time, the brake jitter is confirmed and an alarm command is issued to the brake jitter alarm.

[0008] The brake jitter recognition button is connected to the ESC controller to turn on or off the brake jitter recognition function; the brake jitter alarm is used to receive and execute the alarm command sent by the ESC controller.

[0009] Another aspect of the present invention discloses a method for intelligently identifying vehicle brake jitter, comprising the following steps:

[0010] S1: Press the brake jitter recognition button to turn on the vehicle brake jitter recognition function; if the brake jitter recognition button is not pressed, the vehicle jitter recognition function is turned off and the vehicle brake jitter recognition is not performed;

[0011] S2: The ESC controller receives and determines whether the vehicle speed signal collected by the wheel speed sensor and the brake pressure signal collected by the vehicle master cylinder pressure sensor reach a preset first threshold; if it is determined that both the vehicle speed signal and the brake pressure signal reach the preset first threshold, it determines whether the ABS system or the EBD system intervenes during the braking process, if not, executes step S3, if yes, executes step S7;

[0012] S3: Identify whether it is brake jitter by using a brake jitter identification algorithm. If it is brake jitter, execute step S4; if not, execute step S7;

[0013] S4: The ESC controller detects and determines whether the vehicle speed signal collected by the wheel speed sensor and the brake pressure signal collected by the vehicle master cylinder pressure sensor reach a preset second threshold value and the brake jitter duration is greater than a preset time. When it is determined that the vehicle speed signal collected by the wheel speed sensor and the brake pressure signal collected by the vehicle master cylinder pressure sensor reach the preset second threshold value and the brake jitter duration is greater than the preset time, step S5 is executed; if the vehicle speed signal or the brake pressure signal does not reach the preset second threshold value, or the brake jitter duration is less than the preset time, step S7 is executed;

[0014] S5: The ESC controller confirms the brake judder and sends an alarm command to the brake judder alarm;

[0015] S6: The brake judder alarm receives the alarm command from the ESC controller and issues a brake judder alarm;

[0016] S7: The ESC controller does not need to send an alarm command to the brake judder alarm.

[0017] Further, after the brake judder recognition button is pressed, steps S1-S7 are executed.

[0018] Furthermore, a wheel speed sensor is used to obtain a vehicle speed signal and transmit it to the ESC controller.

[0019] Furthermore, a brake pressure signal is acquired by a master cylinder pressure sensor and transmitted to an ESC controller.

[0020] Furthermore, the preset first thresholds of the vehicle speed signal and the brake pressure signal are: the vehicle speed signal is greater than 60 kph, and the brake pressure signal is greater than 10 bar.

[0021] Furthermore, the preset second thresholds of the vehicle speed signal and the brake pressure signal are: the vehicle speed signal is greater than 40 kph, and the brake pressure signal is greater than 10 bar.

[0022] Furthermore, the preset braking tremor duration is greater than 3 seconds.

[0023] Furthermore, the brake judder recognition algorithm includes:

[0024] Receive the brake pressure signal B collected by the vehicle master cylinder pressure sensor p , record the brake pressure signal frequency f s1 , the collected brake pressure signal B p Frequency domain analysis via discrete Fourier transform:

[0025]

[0026] The time domain signal x(n) is the brake pressure value, the number of sampling points is N1=512, and the effective frequency range is 0~f s1 / 2Hz, the amplitude conversion coefficient is N1 / 2;

[0027] Receive the steering column torque signal L monitored by the steering wheel torque sensor m , record the torque signal frequency as f s2 , the collected torque signal L m Frequency domain analysis via discrete Fourier transform:

[0028]

[0029] Among them, the time domain signal y(n) is the torque signal, the number of sampling points is N2=1024, and the effective frequency range is 0~f s2 / 2Hz, the amplitude conversion coefficient is N2 / 2;

[0030] Define brake pressure signal B p The identification function is:

[0031]

[0032] Among them, Z Bp is the amplitude at each frequency f after discrete Fourier transform, and defines f smin =10Hz;

[0033] Define the torque signal L m The identification function is:

[0034]

[0035] Among them, Z Lm is the amplitude at each frequency f after discrete Fourier transform, and defines f smin =10Hz;

[0036] When the brake pressure signal B p and torque signal L m The accumulated amplitude exceeds the threshold λ max , it is identified as brake judder.

[0037] Beneficial technical effects:

[0038] 1. The present invention discloses a system for intelligently identifying vehicle brake jitter, including a wheel speed sensor, an EPS electric power steering controller, an ESC controller, a brake jitter identification button and a brake jitter alarm. The brake jitter identification button is designed by using the existing ESC controller, electric power steering controller and wheel speed sensor of the vehicle. The user can select or cancel the function, which is completely updated through the software logic of the ESC controller and the EPS electric power steering controller. There is no need to modify the vehicle chassis and other parts of the vehicle body, and no additional material cost and mold cost is required;

[0039] 2. The present invention discloses a method for intelligently identifying vehicle brake jitter, comprising the following steps: S1: pressing a brake jitter identification button to turn on a function for identifying vehicle brake jitter; if the brake jitter identification button is not pressed, the vehicle jitter identification function is in an off state, and vehicle brake jitter identification is not performed; S2: an ESC controller receives and determines whether a vehicle speed signal collected by a wheel speed sensor and a brake pressure signal collected by a vehicle master cylinder pressure sensor reach a preset first threshold; if it is determined that both the vehicle speed signal and the brake pressure signal reach the preset first threshold, it is determined whether an ABS system or an EBD system intervenes during braking, if not, step S3 is executed, if yes, step S7 is executed; S3: identifying whether it is brake jitter through a brake jitter identification algorithm, if yes, step S4 is executed, if no, step S7 is executed; S4: the ESC controller detects and determines whether the vehicle speed signal collected by the wheel speed sensor and the vehicle master cylinder pressure sensor reach a preset first threshold Whether the brake pressure signal collected by the pressure sensor reaches the preset second threshold and the brake jitter duration is greater than the preset time. When it is determined that the vehicle speed signal collected by the wheel speed sensor and the brake pressure signal collected by the vehicle master cylinder pressure sensor reach the preset second threshold and the brake jitter duration is greater than the preset time, execute step S5; if the vehicle speed signal or the brake pressure signal does not reach the preset second threshold, or the brake jitter duration is less than the preset time, execute step S7; S5: The ESC controller confirms the brake jitter and sends an alarm command to the brake jitter alarm; S6: The brake jitter alarm receives the alarm command issued by the ESC controller and issues a brake jitter alarm; S7: The ESC controller does not need to send an alarm command to the brake jitter alarm; Based on the typical characteristics of vehicle brake jitter, by monitoring the vehicle speed, brake pressure, steering wheel torque and other signals, the frequency domain characteristics of the vehicle during brake jitter are calculated to effectively identify the vehicle's brake jitter. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solution of the present invention, the drawings required for describing the embodiments are briefly introduced below.

[0041] Figure 1 A schematic diagram of the whole vehicle layout of a system for identifying vehicle brake jitter according to the present invention;

[0042] Figure 2 A flowchart of a method for identifying vehicle brake jitter according to the present invention;

[0043] Figure 3 The wheel vibration diagram identified by the left and right front wheel vibration acceleration sensors;

[0044] Figure 4 It is the time domain characteristics of different signals during vehicle braking judder;

[0045] Figure 5(a) shows the frequency domain characteristics of the brake pressure signal during vehicle brake judder;

[0046] Figure 5(b) shows the frequency domain characteristics of the brake pressure signal during normal vehicle driving;

[0047] Figure 6(a) shows the frequency domain characteristics of the steering wheel torque signal during vehicle braking judder;

[0048] Figure 6(b) shows the frequency domain characteristics of the steering wheel torque signal during normal vehicle driving;

[0049] Figure 7 This is a schematic diagram of brake pedal vibration caused by wheel vibration;

[0050] Figure 8 This is a schematic diagram of steering wheel vibration caused by wheel vibration.

[0051] Among them, 1-ESC controller, 2-EPS electric power steering controller, 3-wheel speed sensor, 4-brake vibration recognition button, 5-brake vibration alarm, DETAILED DESCRIPTION

[0052] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0053] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0054] The principle of the vehicle brake jitter identification system and method disclosed in the present invention, or the starting point of the technical solution of the present invention, is:

[0055] Vehicle brake judder occurs under specific driving conditions. When the vehicle is traveling at high speed, when the driver steps on the brake pedal, brake hydraulics are established in the brake system, which actuates the friction plates and friction discs in the wheel side brakes to generate friction. The system kinetic energy is converted into heat energy to slow down the vehicle.

[0056] Due to the wear of the friction disc or the presence of unexpected material hard spots inside the parts, part failure will cause uneven end face vibration during the friction process between the friction plate and the friction disc. The brake is installed on the wheel assembly. The vibration of the brake causes the tire to vibrate, which is transmitted to the passenger compartment through the suspension system, making the driver subjectively feel brake judder. This vibration is particularly severe and continuous when driving at high speeds.

[0057] The components associated with tires are mainly chassis system parts. Chassis brake system parts and chassis steering system parts absorb most of the energy. For the brake system, its energy transmission path is as follows: Figure 7 As shown, the vibration energy is transmitted through the wheels, through the hydraulic circuit of the brake line to the brake master cylinder, and then to the brake pedal in the passenger compartment.

[0058] For the steering system, the energy transmission path is as follows Figure 8 As shown, the vibration energy is transmitted through the wheel and mechanical connection to the steering knuckle, steering rod, worm gear steering transmission mechanism, steering column, power motor, and finally to the steering wheel in the passenger compartment.

[0059] From this, it can be understood that when brake jitter occurs, the relevant signal value also jitters, which is displayed as an increase in high-frequency vibration components in the frequency domain. By identifying the characteristics in the frequency domain, the vibration characteristics of the entire vehicle can be effectively distinguished.

[0060] Therefore, the present invention discloses a system for intelligently identifying vehicle brake tremor, see Figure 1, specifically including wheel speed sensor, EPS electric power steering controller, ESC controller, brake jitter recognition button and brake jitter alarm, wherein the wheel speed sensor is fixedly arranged on each wheel to collect vehicle speed signal and transmit it to ESC controller; EPS electric power steering controller is integrated with steering wheel torque sensor to monitor the torque of steering column under steering wheel and transmit it to ESC controller through bus; ESC controller is integrated with vehicle master cylinder pressure sensor to receive vehicle speed signal collected by wheel speed sensor and torque signal of steering column monitored by steering wheel torque sensor; when vehicle speed signal collected by wheel speed sensor and brake pressure signal collected by vehicle master cylinder pressure sensor reach preset first threshold value, brake jitter recognition module arranged in ESC controller identifies whether vehicle is brake jitter; if it is brake jitter, ESC controller detects and determines vehicle speed collected by wheel speed sensor. The brake jitter alarm is used to receive and execute the alarm command sent by the ESC controller. The brake jitter identification button is designed using the vehicle's existing ESC controller, electric power steering controller and wheel speed sensor to allow the user to select or cancel the function. The function is completely updated through the ESC controller and EPS electric power steering controller software logic. There is no need to modify the vehicle chassis and other body parts, and no additional material costs or mold costs.

[0061] The working process of the intelligent vehicle brake vibration recognition system disclosed in the present invention is as follows:

[0062] The wheel speed sensor detects the vehicle speed in real time and transmits the detected speed signal to the ESC controller. The master cylinder pressure sensor detects the brake pressure in real time and transmits the detected brake pressure signal to the ESC controller. The steering wheel torque sensor detects the torque of the steering column under the steering wheel in real time and transmits the detected torque signal of the steering column to the ESC controller. The ESC controller receives the vehicle speed signal, the brake pressure signal and the torque signal. The ESC controller determines whether the received vehicle speed signal and the brake pressure signal are greater than a preset first threshold. If they are greater than the preset first threshold, the brake jitter recognition module set inside the ESC controller identifies whether the vehicle is brake jittering. If it is identified as brake jitter, the ESC controller again determines whether the vehicle speed signal and the brake pressure signal are greater than a preset second threshold and the brake jitter duration is greater than a preset time, then it is determined that the vehicle is brake jittering, and an alarm command is sent to the brake jitter alarm. The brake jitter alarm receives the alarm command and sends an alarm signal to remind the driver in time.

[0063] Another aspect of the present invention discloses a method for intelligently identifying vehicle brake jitter, see Figure 2 , specifically including the following steps:

[0064] S1: Press the brake jitter recognition button to turn on the vehicle brake jitter recognition function; if the brake jitter recognition button is not pressed, the vehicle jitter recognition function is turned off and the vehicle brake jitter recognition is not performed;

[0065] Specifically, after pressing the brake judder recognition button, steps S1-S7 are executed;

[0066] S2: The ESC controller receives and determines whether the vehicle speed signal collected by the wheel speed sensor and the brake pressure signal collected by the vehicle master cylinder pressure sensor reach a preset first threshold; if it is determined that both the vehicle speed signal and the brake pressure signal reach the preset first threshold, it determines whether the ABS system or the EBD system intervenes during the braking process, if not, executes step S3, if yes, executes step S6;

[0067] Specifically, the wheel speed sensor is used to obtain the vehicle speed signal and transmit it to the ESC controller. The master cylinder pressure sensor is used to obtain the brake pressure signal and transmit it to the ESC controller. This application sets the first thresholds of the vehicle speed signal and the brake pressure signal based on actual operation data and experimental data: the vehicle speed signal is greater than 60kph, and the brake pressure signal is greater than 10bar.

[0068] S3: Identify whether it is brake jitter by using a brake jitter identification algorithm. If it is brake jitter, execute step S4; if not, execute step S7;

[0069] Specifically, the brake judder recognition algorithm includes:

[0070] Receive the brake pressure signal B collected by the vehicle master cylinder pressure sensor p , record the brake pressure signal frequency f s1 , the collected brake pressure signal B p Frequency domain analysis via discrete Fourier transform:

[0071]

[0072] Among them, the time domain signal x(n) is the braking pressure value. In order to speed up the Fourier transform calculation in engineering signal processing, the number of sampling points N1=512 is taken. It should be noted that the amplitude transformation should be performed when calculating the amplitude in the spectrum diagram, that is, the amplitude X(k) after discrete Fourier transform needs to be multiplied by the amplitude transformation coefficient N1 / 2 to obtain the true amplitude at each frequency. At the same time, since the X(k) sequence consists of two conjugate complex sequences, the 0~f in the spectrum diagram s1 The frequency of / 2 is independent and effective;

[0073] Receive the steering column torque signal L monitored by the steering wheel torque sensor m , record the torque signal frequency as f s2 , the collected torque signal L m Frequency domain analysis via discrete Fourier transform:

[0074]

[0075] Among them, the time domain signal y(n) is the torque signal. In order to speed up the Fourier transform calculation in engineering signal processing, the number of sampling points N2=1024 is taken. It should be noted that the amplitude transformation should be performed when calculating the amplitude in the spectrum diagram, that is, the amplitude Y(k) after discrete Fourier transform needs to be multiplied by the amplitude transformation coefficient N1 / 2 to obtain the true amplitude at each frequency. At the same time, since the Y(k) sequence consists of two conjugate complex sequences, the 0~f in the spectrum diagram s1 The frequency of / 2 is independent and effective;

[0076] In order to ensure the robustness of the recognition system, a system alarm is issued only when the feature is reproduced stably and continuously, so the recognition function is defined:

[0077] Define brake pressure signal B p The identification function is:

[0078]

[0079] Among them, Z Bp is the amplitude at each frequency f after discrete Fourier transform, and defines f smin =10Hz;

[0080] Define the torque signal Lm The identification function is:

[0081]

[0082] Among them, Z Lm is the amplitude at each frequency f after discrete Fourier transform, and defines f smin =10Hz;

[0083] When the brake pressure signal B p and torque signal L m The accumulated amplitude exceeds the threshold λ max It is recognized as brake shudder. It can be understood that the recognition system will not affect the vehicle driving assistance system or the driver's control requirements for the vehicle.

[0084] S4: The ESC controller detects and determines whether the vehicle speed signal collected by the wheel speed sensor and the brake pressure signal collected by the vehicle master cylinder pressure sensor reach a preset second threshold value and the brake jitter duration is greater than a preset time. When it is determined that the vehicle speed signal collected by the wheel speed sensor and the brake pressure signal collected by the vehicle master cylinder pressure sensor reach the preset second threshold value and the brake jitter duration is greater than the preset time, step S4 is executed; if the vehicle speed signal or the brake pressure signal does not reach the preset second threshold value, or the brake jitter duration is less than the preset time, step S6 is executed;

[0085] Specifically, the present application is set according to actual operating data and experimental data: the preset second threshold values ​​of the vehicle speed signal and the brake pressure signal are: the vehicle speed signal is greater than 40 kph, and the brake pressure signal is greater than 10 bar; the preset brake jitter duration is greater than 3 s.

[0086] S5: The ESC controller confirms the brake judder and sends an alarm command to the brake judder alarm;

[0087] S6: The brake judder alarm receives the alarm command from the ESC controller and issues a brake judder alarm;

[0088] S7: The ESC controller does not need to send an alarm command to the brake judder alarm.

[0089] The following actual test is conducted to verify the effect of the intelligent vehicle brake vibration identification system and method disclosed in the present invention:

[0090] By using the communication function of the ESC controller and the electric power steering controller equipped in mass production vehicles, the recognition logic is compiled through CANoe equipment and software to realize the monitoring of the frequency domain characteristics of the signal set in the software function. A vibration acceleration sensor is installed on the vehicle brake to monitor the state of the vibration source. Combined with the driver's subjective judgment of the vibration, the effect of the vehicle brake vibration recognition function is examined. See Figure 3 .

[0091] The time domain characteristics of the main signals of vehicle brake vibration are recorded as follows Figure 4 : When driving at high speed, the driver's active braking brake pressure and steering wheel torque both experience severe high-frequency vibrations; during non-braking or no brake jitter, the signal is smooth; as shown in Figure 5(a) and Figure 5(b), and Figure 6(a) and Figure 6(b), the frequency domain characteristics of the main signals during brake jitter and during normal driving are significantly different, and are consistent with the driver's subjective feedback. Therefore, the method for identifying vehicle brake jitter disclosed in the present invention can effectively identify brake jitter.

[0092] The vehicle brake jitter identification system disclosed in the present invention utilizes the vehicle's existing ESC controller, EPS electric power steering controller and wheel speed sensor, and is designed to add a brake jitter identification button. The driver and passengers can turn on or off this function according to actual needs. The function is completely controlled by the ESC controller and EPS electric power steering controller software, and there is no need to modify the vehicle chassis and other body parts, and no additional material cost and mold cost. The vehicle brake jitter identification method disclosed in the present invention starts from the typical phenomenon of jitter, identifies the vehicle brake jitter in a targeted manner, and promptly feeds back the identification result to the driver, thereby improving driving safety.

[0093] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0094] The above embodiments are only descriptions of the preferred implementation modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary engineering and technical personnel in the field should fall within the protection scope determined by the claims of the present invention.

Claims

1. A system for intelligently identifying vehicle brake vibration, characterized in that: include: A wheel speed sensor is fixedly mounted on each wheel to collect a vehicle speed signal and transmit it to the ESC controller; EPS electric power steering controller, wherein the EPS electric power steering controller is integrated with a steering wheel torque sensor to monitor the torque of the steering column under the steering wheel and transmit it to the ESC controller through a bus; An ESC controller, wherein the ESC controller is integrated with a vehicle master cylinder pressure sensor, receives a vehicle speed signal collected by the wheel speed sensor and a torque signal of a steering column monitored by the steering wheel torque sensor, and when the vehicle speed signal collected by the wheel speed sensor and the brake pressure signal collected by the vehicle master cylinder pressure sensor reach a preset first threshold, a brake jitter identification module provided inside the ESC controller identifies whether the vehicle is in brake jitter, and identifies whether it is brake jitter through a brake jitter identification algorithm, and identifies brake jitter when the amplitude accumulation of the brake pressure signal and the torque signal both exceed the threshold; if it is identified as brake jitter, the ESC controller detects and determines whether the vehicle speed signal collected by the wheel speed sensor and the brake pressure signal collected by the vehicle master cylinder pressure sensor reach a preset second threshold and the brake jitter duration is greater than a preset time, and when it is determined that the vehicle speed signal collected by the wheel speed sensor and the brake pressure signal collected by the vehicle master cylinder pressure sensor reach the preset second threshold and the brake jitter duration is greater than the preset time, the brake jitter is confirmed and an alarm command is issued to the brake jitter alarm; A brake judder recognition button, which is connected to the ESC controller and is used to turn on or off a brake judder recognition function; The brake tremor alarm is used to receive and execute the alarm command sent by the ESC controller.

2. A method for intelligently identifying vehicle brake jitter, the method being applied to the system as claimed in claim 1, characterized in that: The following steps are involved: S1: Press the brake jitter recognition button to turn on the vehicle brake jitter recognition function; if the brake jitter recognition button is not pressed, the vehicle jitter recognition function is turned off and the vehicle brake jitter recognition is not performed; S2: The ESC controller receives and determines whether the vehicle speed signal collected by the wheel speed sensor and the brake pressure signal collected by the vehicle master cylinder pressure sensor reach a preset first threshold; if it is determined that both the vehicle speed signal and the brake pressure signal reach the preset first threshold, it determines whether the ABS system or the EBD system intervenes during the braking process, if not, executes step S3, if yes, executes step S7; S3: Identify whether it is brake jitter by using a brake jitter identification algorithm. If it is brake jitter, execute step S4; if not, execute step S7; S4: The ESC controller detects and determines whether the vehicle speed signal collected by the wheel speed sensor and the brake pressure signal collected by the vehicle master cylinder pressure sensor reach a preset second threshold value and the brake jitter duration is greater than a preset time. When it is determined that the vehicle speed signal collected by the wheel speed sensor and the brake pressure signal collected by the vehicle master cylinder pressure sensor reach the preset second threshold value and the brake jitter duration is greater than the preset time, step S5 is executed; if the vehicle speed signal or the brake pressure signal does not reach the preset second threshold value, or the brake jitter duration is less than the preset time, step S7 is executed; S5: The ESC controller confirms the brake judder and sends an alarm command to the brake judder alarm; S6: The brake judder alarm receives the alarm command from the ESC controller and issues a brake judder alarm; S7: The ESC controller does not need to send an alarm command to the brake judder alarm.

3. The method for intelligently identifying vehicle brake jitter according to claim 2, characterized in that: Also includes: After pressing the brake judder recognition button, execute steps S1-S7.

4. The method for intelligently identifying vehicle brake jitter according to claim 2, characterized in that: The wheel speed sensor is used to obtain the vehicle speed signal and transmit it to the ESC controller.

5. The method for intelligently identifying vehicle brake jitter according to claim 2, characterized in that: The master cylinder pressure sensor is used to obtain the brake pressure signal and transmit it to the ESC controller.

6. The method for intelligently identifying vehicle brake jitter according to claim 2, characterized in that: The first threshold values ​​preset for the vehicle speed signal and the brake pressure signal are: the vehicle speed signal is greater than 60 kph, and the brake pressure signal is greater than 10 bar.

7. The method for intelligently identifying vehicle brake jitter according to claim 2, characterized in that: The preset second thresholds of the vehicle speed signal and the brake pressure signal are: the vehicle speed signal is greater than 40 kph, and the brake pressure signal is greater than 10 bar.

8. The method for intelligently identifying vehicle brake jitter according to claim 2, characterized in that: The preset brake judder duration is greater than 3s.

9. The method for intelligently identifying vehicle brake jitter according to claim 2, characterized in that: The brake judder recognition algorithm comprises the following steps: Receive the brake pressure signal B collected by the vehicle master cylinder pressure sensor p , record the brake pressure signal frequency f s1 , the collected brake pressure signal B p Frequency domain analysis via discrete Fourier transform: The time domain signal x(n) is the brake pressure value, the number of sampling points is N1=512, and the effective frequency range is 0~f s1 / 2Hz, the amplitude conversion coefficient is N1 / 2; Receive the steering column torque signal L monitored by the steering wheel torque sensor m , record the torque signal frequency as f s2 , the collected torque signal L m Frequency domain analysis via discrete Fourier transform: Among them, the time domain signal y(n) is the torque signal, the number of sampling points is N2=1024, and the effective frequency range is 0~f s2 / 2Hz, the amplitude conversion coefficient is N2 / 2; Define brake pressure signal B p The identification function is: Among them, Z Bp is the amplitude at each frequency f after discrete Fourier transform, and defines f smin =10Hz; Define the torque signal L m The identification function is: Among them, Z Lm is the amplitude at each frequency f after discrete Fourier transform, and defines f smin =10Hz; When the brake pressure signal B p and torque signal L m The accumulated amplitude exceeds the threshold λ max , it is identified as brake judder.

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