CN119428599A - Brake control method and system of distributed brake system - Google Patents
Brake control method and system of distributed brake system Download PDFInfo
- Publication number
- CN119428599A CN119428599A CN202510048695.9A CN202510048695A CN119428599A CN 119428599 A CN119428599 A CN 119428599A CN 202510048695 A CN202510048695 A CN 202510048695A CN 119428599 A CN119428599 A CN 119428599A
- Authority
- CN
- China
- Prior art keywords
- wheel
- deceleration
- vehicle
- braking
- clamping force
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Regulating Braking Force (AREA)
Abstract
本申请实施例提供了一种分布式制动系统的制动控制方法及系统，应用于车辆，制动域控制器与轮边控制器通过高速总线通讯连接，轮边控制器与轮速传感器通过信号线通讯连接；在高速总线通讯故障时，制动域控制器进入故障状态，轮边控制器通过电子卡钳向车辆的车轮施加目标夹紧力，并根据轮速传感器采集到的轮速信号控制电子卡钳，实现车轮制动。通过轮边控制器实现车辆的安全制动，提高分布式制动系统的安全性和鲁棒性，通过目标夹紧力控制车轮以最低减速度实现安全制动，保证车辆即使在高速总线通讯故障，无法通过制动域控制器控制时，依然可以实现安全制动，提高安全性和系统鲁棒性。
The embodiment of the present application provides a brake control method and system for a distributed brake system, which is applied to a vehicle, wherein the brake domain controller is connected to the wheel side controller via a high-speed bus communication, and the wheel side controller is connected to the wheel speed sensor via a signal line communication; when the high-speed bus communication fails, the brake domain controller enters a fault state, and the wheel side controller applies a target clamping force to the vehicle's wheel through an electronic caliper, and controls the electronic caliper according to the wheel speed signal collected by the wheel speed sensor to achieve wheel braking. The safe braking of the vehicle is achieved through the wheel side controller, which improves the safety and robustness of the distributed brake system. The wheels are controlled by the target clamping force to achieve safe braking with the minimum deceleration, ensuring that the vehicle can still achieve safe braking even when the high-speed bus communication fails and cannot be controlled by the brake domain controller, thereby improving safety and system robustness.
Description
Technical Field
The application relates to the field of vehicle braking, in particular to a braking control method and system of a distributed braking system.
Background
A distributed brake system (shown in fig. 1) is precisely built from an electronic brake pedal, a brake domain controller, and four wheel side controllers (Wheel Control Unit, WCU). Each WCU is closely connected with a wheel speed Sensor (WHEEL SPEED Sensor, WSS), so that the accurate monitoring of the wheel speed is realized, and the electronic calipers of the single wheel are independently controlled.
The electronic brake pedal is used for converting the brake control of a driver into an electric signal and transmitting the electric signal to the brake domain controller, and simultaneously converting the electric signal into a whole-vehicle high-speed bus signal which is used as a redundant signal channel and transmitted to the brake domain controller and the four wheel side controllers in the electric control brake system. The brake domain controller is used as a brain to analyze the electric signal of the electronic brake pedal, correctly identify the brake intention of a driver, then perform logic operation of a brake boosting function, output a brake control command to the wheel side controller through a whole-vehicle high-speed bus, and the wheel speed sensor is used as a sensor unit for dynamically sensing wheels and is a necessary input signal of a chassis control function.
In the distributed braking system, a wheel speed sensor is directly connected to a wheel side controller, sensor power supply is carried out through the wheel side controller, signals are acquired and processed, and signals of four wheel speed sensors are sent to a whole vehicle high-speed bus, the wheel side controller receives a wheel side braking instruction of a braking domain controller, clamping and releasing of an electronic caliper are controlled, and a parking control interface can be provided.
In order to realize the wheel Anti-lock function (Anti-lock Braking System, ABS), the brake domain controller receives the wheel speed sensors on the high-speed bus, performs rationality verification on the signals of the four wheel speed sensors, and completes the calculation of the reference vehicle speed of the whole vehicle and the calculation of the slip rate of each wheel. The brake domain controller adjusts single-wheel braking force instructions in real time according to the slip rate of each wheel, and locking of the wheels is avoided.
However, when the high-speed communication bus of the whole vehicle fails, how to realize normal braking of the vehicle is a technical problem to be solved urgently.
Disclosure of Invention
The application aims to solve the technical problem of how to realize safe braking of a vehicle when a high-speed communication bus in a distributed braking system fails in the prior art, and therefore, the application provides a braking control method and a braking control system of the distributed braking system, which realize safe braking of the vehicle through a wheel side controller when the high-speed bus fails and improve the safety and the robustness of the distributed braking system.
The embodiment of the application provides a braking control method of a distributed braking system, which is applied to a vehicle, wherein the distributed braking system comprises a braking domain controller, a wheel edge controller, a wheel speed sensor and an electronic caliper, wherein the braking domain controller is in communication connection with the wheel edge controller through a high-speed bus, and the wheel edge controller is in communication connection with the wheel speed sensor through a signal wire;
When the high-speed bus communication fails, the brake domain controller enters a failure state, the wheel side controller applies target clamping force to wheels of a vehicle through the electronic calipers, and controls the electronic calipers according to wheel speed signals acquired by the wheel speed sensor to realize wheel braking, wherein the target clamping force is used for controlling the wheels to brake at the lowest deceleration, and the wheel speed sensor acquires the wheel speed signals in real time when the vehicle moves.
By adopting the technical scheme, when the high-speed bus in the distributed braking system fails, the safety braking of the vehicle is realized through the wheel side controller, the safety and the robustness of the distributed braking system are improved, the wheels are controlled by the target clamping force to realize the safety braking at the minimum deceleration, and the safety braking can be realized even if the vehicle fails to be controlled through the braking domain controller in high-speed bus communication failure, so that the safety and the system robustness are improved.
In some embodiments, the wheel side controller controls the wheel to brake at a minimum deceleration in accordance with the wheel speed signal after applying the target clamping force to the wheel via the electronic caliper.
By adopting the technical scheme, when a high-speed bus in the distributed braking system fails, the wheel side controller applies target clamping force to the wheels, and then controls the vehicle to brake at the lowest deceleration through the wheel speed signals acquired in real time, so that the condition that the vehicle is suddenly and greatly decelerated or locked is prevented, the vehicle is unstable is avoided, the safety braking of the vehicle is ensured, and the safety is improved.
In some embodiments, the wheel-side controller calculates a wheel deceleration and a wheel deceleration rate of change from the wheel speed signal;
Determining whether to release the target clamping force according to the wheel deceleration and a deceleration threshold value, wherein the deceleration threshold value is used for judging whether the wheels are locked;
And/or,
And determining whether to release the target clamping force according to the change rate of the wheel deceleration and a change rate threshold value, wherein the change rate threshold value is used for judging the tendency of locking of the wheels.
In some embodiments, if the wheel deceleration is greater than the deceleration threshold, controlling the electronic caliper to release the target clamping force;
if the wheel deceleration is less than or equal to the wheel deceleration threshold, controlling the electronic caliper to apply a target clamping force;
And/or,
If the change rate of the wheel deceleration is larger than the change rate threshold value, controlling the electronic caliper to release the target clamping force;
and if the change rate of the wheel deceleration is less than or equal to the change rate threshold value, controlling the electronic caliper to apply the target clamping force.
By adopting the technical scheme, the wheel side controller prevents the occurrence of wheel locking or sudden large-amplitude deceleration in the braking process of the vehicle according to the wheel deceleration threshold value and the wheel deceleration change rate threshold value, ensures the safety of vehicle braking, and is the stable braking of the vehicle.
In some embodiments, the wheel-side controller calculates a wheel deceleration and a wheel deceleration rate of change from the wheel speed signal, comprising:
Obtaining the average wheel speed of the first acquisition period according to the wheel speed signal of the first acquisition period acquired by the wheel speed sensor and the average wheel speed of N-1 acquisition periods before the first acquisition period, wherein N is a positive integer;
And obtaining the wheel deceleration and the wheel deceleration change rate according to the average wheel speeds of the first acquisition period and the second acquisition period, wherein the second acquisition period is the previous period of the first acquisition period.
By adopting the technical scheme, in the braking process of the vehicle, the wheel speed sensor acquires the wheel speed signals of the wheels in real time, calculates the wheel deceleration and the wheel deceleration change rate, can monitor the braking effect of the vehicle in real time, and ensures the safe braking of the vehicle.
In some embodiments, the target clamping force for different conditions of the vehicle is determined based on the minimum deceleration while the braking system of the vehicle is calibrated.
In some embodiments, the vehicle includes front and rear wheels, the target clamping force including a front wheel clamping force and a rear wheel clamping force;
Determining front wheel braking force applied to the front wheels by the wheel side controller and rear wheel braking force applied to the rear wheels by the wheel side controller according to front wheel normal reaction force applied to the front wheels and rear wheel normal reaction force applied to the rear wheels when the vehicle brakes at the minimum deceleration;
And obtaining the front wheel clamping force of the front wheels and the rear wheel clamping force of the rear wheels according to the front wheel braking force and the rear wheel braking force.
In some embodiments, the front wheels include left and right front wheels, and the rear wheels include left and right rear wheels;
The left front wheel and the right front wheel are controlled by the clamping force of the front wheels;
the left rear wheel and the right rear wheel are controlled by the rear wheel clamping force.
By adopting the technical scheme, the four wheels of the vehicle are simultaneously braked and controlled, so that the safety of vehicle braking can be ensured.
In some embodiments, the brake domain controller sends a warning message to the vehicle when a fault condition is entered.
By adopting the technical scheme, when the high-speed bus fails, warning information can be sent to the vehicle to remind a driver of the vehicle to take safety braking measures, or the braking system of the vehicle is overhauled, so that the safety braking and safety of the vehicle can be ensured.
The embodiment of the application also provides a brake control system of the distributed brake system, which comprises the brake control method of the distributed brake system.
The application provides a braking control method and a braking control system of a distributed braking system, which realize safe braking of a vehicle through a wheel side controller when a high-speed bus in the distributed braking system fails, improve the safety and the robustness of the distributed braking system, control wheels through a target clamping force to realize safe braking at the minimum deceleration, ensure that the vehicle can still realize safe braking even if the high-speed bus fails to be controlled through a braking domain controller, improve the safety and the robustness of the system, furthest ensure that the vehicle can still stop braking when the distributed braking system fails, effectively shorten the influence time of the failure, ensure the operation safety of the vehicle, have stronger universality and expansibility, provide powerful support for maintenance and management, reduce the maintenance cost, and the wheel side controller does not need to increase more redundant communication buses, thereby saving the cost.
Drawings
FIG. 1 is a schematic diagram of a distributed brake system according to an embodiment of the present application;
FIG. 2 is a schematic diagram of a high speed bus failure in a distributed brake system according to an embodiment of the present application;
FIG. 3 is a graph illustrating a wheel speed curve according to an embodiment of the present application;
FIG. 4 is a schematic illustration of a wheel deceleration curve according to an embodiment of the present application;
FIG. 5 is a graphical representation of a rate of change of wheel deceleration in accordance with an embodiment of the present application;
reference numerals illustrate:
WSS, wheel speed sensor;
FL_WCU, left front wheel controller, FR_WCU, right front wheel controller, RL_WCU, left rear wheel controller, RR_WCU, right rear wheel controller;
Vt, wheel speed, a, acceleration; the change rate of the wheel deceleration, t, time;
minimum deceleration; A deceleration threshold; A rate of change threshold;
S1, releasing a target clamping force at S1;
s2, applying a target clamping force at S2.
Detailed Description
Further advantages and effects of the present application will become apparent to those skilled in the art from the disclosure of the present specification, by describing the embodiments of the present application with specific examples. While the description of the application will be presented in connection with certain embodiments, it is not intended to limit the features of this application to only this embodiment. Rather, the purpose of the present application is to cover other alternatives or modifications, which may be extended by the claims based on the application. The following description contains many specific details for the purpose of providing a thorough understanding of the present application. The application may be practiced without these specific details. Furthermore, some specific details are omitted from the description in order to avoid obscuring the application. It should be noted that, without conflict, the embodiments of the present application and features of the embodiments may be combined with each other.
It should be noted that in this specification, like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.
In the description of the present application, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present application, unless explicitly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected, mechanically connected, electrically connected, directly connected, indirectly connected via an intervening medium, or in communication between two elements. The specific meaning of the above terms in the present application will be understood in specific cases by those of ordinary skill in the art.
In the description of the present application, it should be understood that "electrically connected" in the present application may be understood as that components are in physical contact and electrically connected, and may be understood as that different components in a circuit configuration are connected by a printed circuit board (printed circuit board, PCB) copper foil or a wire or other physical circuit capable of transmitting an electrical signal. "coupled by" is understood to mean electrically isolated by indirect coupling. An indirect coupling is understood to be a contactless coupling, wherein the coupling phenomenon, as understood by a person skilled in the art, means a phenomenon in which there is a close fit and interaction between the input and output of two or more circuit elements or electrical networks and energy is transferred from one side to the other by the interaction. For the purpose of making the objects, technical solutions and advantages of the present application more apparent, embodiments of the present application will be described in further detail below with reference to the accompanying drawings.
In the distributed brake system, as shown in fig. 1, for four wheels of a vehicle, an electronic caliper and corresponding WCU are respectively provided, specifically including a left front wheel side controller (fl_wcu), a right front wheel side controller (fr_wcu), a left rear wheel side controller (rl_wcu) and a right rear wheel side controller (rr_wcu), wherein one Wheel Speed Sensor (WSS) is respectively provided on the four wheels, the WSS is communicatively connected with the corresponding WCU through a signal line, the fl_wcu, fr_wcu, rl_wcu and rr_wcu are communicatively connected with the brake domain controller through a high speed bus, and the electronic brake pedal is communicatively connected with the brake domain controller through a signal line and with all WCU through a high speed bus.
In the prior art, when the brake domain controller, the wheel side controller and the wheel speed sensor are in fault, corresponding brake control methods are adopted to realize the brake control of the vehicle, however, when a high-speed bus is in fault, no corresponding method is adopted to realize the brake control of the vehicle.
When a high-speed bus in the distributed braking system fails, the braking domain controller and the four wheel edge controllers still can work normally, but the braking domain controller cannot transmit a braking instruction to the four wheel edge controllers, and the wheel edge controllers cannot transmit a wheel speed signal to the braking domain controller, so that the braking control of the vehicle cannot be completed normally, and the safety problem exists.
Based on the technical problems, the embodiment of the application provides a braking control method and a braking control system for a distributed braking system, so as to improve the safety and the robustness of the distributed braking system.
The embodiment of the application provides a braking control method and a braking control system of a distributed braking system, which are applied to a vehicle, and as shown in fig. 1, the distributed braking system comprises a braking domain controller, a wheel side controller (WCU), a Wheel Speed Sensor (WSS) and an electronic caliper.
The brake domain controller is connected with the wheel side controller through a high-speed bus in a communication manner, and the wheel side controller is connected with the wheel speed sensor through a signal line in a communication manner.
It is appreciated that communication links are used to describe the transfer of data and the exchange of information between devices, systems or components by some means, such as wired or wireless. By way of example, it may be a high speed bus, signal line, etc.
As shown in fig. 2, when the high-speed bus communication fails, the brake domain controller enters a failure state, the wheel side controller applies a target clamping force to wheels of a vehicle through the electronic calipers, and the electronic calipers are controlled according to wheel speed signals acquired by the wheel speed sensor, so that wheel braking is realized.
Specifically, when a high-speed bus in the distributed braking system fails, the safety braking of the vehicle is realized through the wheel side controller, the safety and the robustness of the distributed braking system are improved, the wheels are controlled by the target clamping force to realize the safety braking at the minimum deceleration, the safety braking can be realized even if the vehicle fails in high-speed bus communication and cannot be controlled through the braking domain controller, and the safety and the system robustness are improved.
The target clamping force is used for controlling wheels to brake at the lowest deceleration, and the wheel speed sensor acquires wheel speed signals in real time when the vehicle moves.
It will be appreciated that in order to ensure public safety, many countries and regions define a minimum deceleration criterion for a vehicle in the event of a brake failure to ensure that the vehicle can still be safely parked in the event of a brake system failure, exemplary motor vehicle operating safety conditions GB 7258 define a minimum deceleration of 2.44 meters per second (m × m) Therefore, in the embodiment of the present application, the setting of the minimum deceleration is not limited, and is mainly set according to the relevant regulations and the situation where the vehicle can be safely stopped in the event of a brake failure, and, for example, the minimum deceleration may be set to be 2.44m +.。
Specifically, when the high-speed BUS communication fails, the brake domain controller enters a failure state, wherein the brake domain controller can default to enter an initialization self-checking state after being electrified, enters a normal working state after self-checking is completed, and enters the failure state when the wheel speed signals of the four wheel side controllers cannot be received or a high-speed BUS OFF state (BUS OFF) failure occurs, and sends warning information of an electric control brake system to a vehicle through a man-machine interaction interface to light a warning lamp.
According to the embodiment of the application, when the high-speed bus fails, warning information can be sent to the vehicle to remind a driver of the vehicle to take safety braking measures, or the braking system of the vehicle is overhauled, so that the safety braking and safety of the vehicle can be ensured.
Further, the wheel side controller controls the wheel to brake at the minimum deceleration according to the wheel speed signal after applying the target clamping force to the wheel through the electronic caliper.
In actual conditions, after the wheel side controller is electrified, the wheel side controller enters a normal working state after an initialization self-checking state, and when no high-speed BUS communication or high-speed BUS OFF is detected, the wheel side controller enters a high-speed BUS network fault state, and the wheel side controller controls the clamping and releasing of the electronic calipers.
Further, in the embodiment of the application, when the braking system of the vehicle checks, the target clamping force of the vehicle under different working conditions is determined according to the minimum deceleration.
The following describes how the target clamping force for different conditions of the vehicle is determined from the minimum deceleration, in connection with specific embodiments.
In an embodiment of the application, the vehicle comprises front wheels and rear wheels, and the target clamping force comprises a front wheel clamping force and a rear wheel clamping force.
In some alternative embodiments, the front wheel braking force and the rear wheel braking force applied to the front wheels by the wheel side controller are determined according to the front wheel normal reaction force applied to the front wheels and the rear wheel normal reaction force applied to the rear wheels when the vehicle is braked at the minimum deceleration, and the front wheel clamping force and the rear wheel clamping force of the rear wheels are obtained according to the front wheel braking force and the rear wheel braking force.
The front wheels comprise left and right front wheels, rear wheels comprise left and right rear wheels, the left and right front wheels are controlled through front wheel clamping force, and the left and right rear wheels are controlled through rear wheel clamping force.
In the embodiment of the application, the four wheels of the vehicle are simultaneously subjected to braking control, so that the safety of vehicle braking can be ensured.
Firstly, under the condition of the same road adhesion coefficient, ideal braking force distribution needs to be considered for the front wheels and the rear wheels in order to ensure that the front wheels and the rear wheels of the vehicle can generate braking force to the maximum extent. At minimum deceleration when the vehicle fails) The front wheel braking force and the rear wheel braking force distribution during braking are checked.
Because the torque generated by the mass center of the vehicle on the front and rear axles is different under different deceleration, the front wheel normal reaction force applied to the front wheels is calculated through the formula (1), and the rear wheel normal reaction force applied to the rear wheels is calculated through the formula (2).
Wherein, represents the normal reaction force of the front wheels, represents the normal reaction force of the rear wheels, L represents the wheelbase of the vehicle, a represents the distance from the center of gravity of the vehicle to the front axle, b represents the distance from the center of gravity of the vehicle to the rear axle, m represents the mass of the whole vehicle, mg represents the gravity of the whole vehicle, represents the height of the center of gravity of the vehicle, g represents the acceleration of gravity (g=9.8 m #)。
After the front wheel normal reaction force and the rear wheel normal reaction force are calculated, the front wheel braking force and the rear wheel braking force are obtained according to the magnitude relation of the front wheel normal reaction force and the rear wheel normal reaction force through a formula (3).
Wherein, Representing the front wheel braking force; Indicating the rear wheel braking force.
Then, according to the front wheel braking force and the rear wheel braking force, the front wheel clamping force and the rear wheel clamping force are obtained, the left side braking force and the right side braking force are considered to be distributed evenly, the front wheel clamping force is obtained through a formula (4), and the rear wheel clamping force is obtained through a formula (5).
Wherein, Representing the front wheel clamping force of the left front wheel; representing the front wheel clamping force of the right front wheel; ; Representing the rear wheel clamping force of the left rear wheel; representing the rear wheel clamping force of the right rear wheel; ; representing the dynamic rolling radius of the front wheel; Representing the dynamic rolling radius of the rear wheel; Indicating the effective brake radius of the front electronic caliper; Indicating the effective braking radius of the rear electronic caliper; representing a front electronic caliper performance factor; representing the post electronic caliper performance factor.
Finally, according to the parameters of the whole vehicle, the minimum deceleration of the vehicle can be obtained) The clamping forces corresponding to the wheel side controllers of the front wheel and the rear wheel under different working conditions are the front wheel clamping force and the rear wheel clamping force.
In the embodiment of the application, the mode of the left and right braking force distribution of the front wheels and the rear wheels is not limited, and the mode can be set according to actual conditions, so that the safety braking of the vehicle is realized through the left and right braking force distribution, and the left and right braking force average distribution is set as an example.
In the embodiment of the application, in order to ensure the stable and safe braking of the vehicle, after the wheel edge controller applies the target clamping force to the wheels through the electronic calipers, the wheel speed sensor still continuously collects the wheel speed signals in real time and uploads the wheel speed signals to the wheel speed sensor, and the wheel speed sensor controls the wheels to brake at the minimum deceleration according to the wheel speed signals.
In some alternative embodiments, the wheel side controller calculates the wheel deceleration and the wheel deceleration change rate according to the wheel speed signal, wherein the wheel side controller obtains the average wheel speed of the first acquisition period according to the wheel speed signal of the first acquisition period acquired by the wheel speed sensor and the average wheel speed of N-1 acquisition periods before the first acquisition period, N is a positive integer, and obtains the wheel deceleration and the wheel deceleration change rate according to the average wheel speed of the first acquisition period and the average wheel speed of the second acquisition period, and the second acquisition period is the previous period of the first acquisition period.
The wheel edge controller calculates the wheel deceleration and the wheel deceleration change rate according to the wheel speed signals, wherein the wheel edge controller obtains a first average speed according to the wheel speed signals of N acquisition periods acquired by the wheel speed sensor in a first round, N is an integer, obtains a second average speed according to the wheel speed signals of N acquisition periods acquired by the wheel speed sensor in a second round, the second round and the second round represent the wheel speed signals continuously acquired by the wheel speed sensor in the acquisition periods when the vehicle moves, and obtains the wheel deceleration and the wheel deceleration change rate according to the speed difference value of the second average speed and the first average speed and the acquisition period.
Specifically, in the braking process of the vehicle, the wheel speed sensor acquires wheel speed signals of the wheels in real time, calculates the wheel deceleration and the wheel deceleration change rate, can monitor the braking effect of the vehicle in real time, and ensures the safe braking of the vehicle.
In some alternative embodiments, the wheel side controller calculates a wheel deceleration and a wheel deceleration rate of change from the wheel speed signal, determines whether to release the target clamping force based on the wheel deceleration and a deceleration threshold, and/or determines whether to release the target clamping force based on the wheel deceleration rate of change and a rate of change threshold.
The deceleration threshold is used for judging whether the wheels are locked or not, and the change rate threshold is used for judging the tendency of locking of the wheels.
Specifically, the wheel side controller prevents the occurrence of wheel locking or sudden large-amplitude deceleration in the braking process of the vehicle according to the wheel deceleration threshold value and the wheel deceleration change rate threshold value, ensures the safety of vehicle braking, and is the stable braking of the vehicle.
Further, the electronic calipers are controlled to release the target clamping force if the wheel deceleration is greater than the deceleration threshold, the electronic calipers are controlled to apply the target clamping force if the wheel deceleration is less than or equal to the wheel deceleration threshold, and/or the electronic calipers are controlled to release the target clamping force if the wheel deceleration change rate is greater than the change rate threshold, and the electronic calipers are controlled to apply the target clamping force if the wheel deceleration change rate is less than or equal to the change rate threshold.
The following describes a case where a wheel speed sensor controls a wheel to brake at a minimum deceleration based on a wheel speed signal by means of a specific embodiment.
Due to the lowest deceleration of the whole vehicle) Has been determined, and therefore, the target value of the wheel deceleration of each wheel is set to. The wheel side controller periodically collects the signal of the wheel speed sensor of the single wheel, analyzes the wheel speed signal, calculates the wheel deceleration and the change rate of the wheel deceleration, and is used for controlling the slip rate of the single wheel.
Specifically, as shown in fig. 3, the horizontal axis is time, the vertical axis is wheel speed, the dotted straight line represents the target wheel speed when braking with the lowest deceleration, the solid curve represents the wheel speed acquired in real time by the wheel speed sensor, the wheel speed sensor signal needs to continuously acquire N acquisition periods (recommended N is an integer of 3-5), the wheel speed signals of the N acquisition periods are averaged, and then the average speed of the last acquisition period is subtracted and divided by the acquisition period [ ]) After that, the wheel deceleration is obtained.
The method includes the steps that when N is 3, a first collecting period is used for collecting wheel speed signals of an Mth period, the wheel speed signals of an M-1 th period and the wheel speed signals of an M-2 th period are required to be collected, M represents any integer, a second collecting period is used for collecting the wheel speed signals of the M-1 th period, the wheel speed signals of the M-2 th period and the wheel speed signals of the M-3 th period are required to be collected, and the wheel deceleration change rate are obtained through a formula (6), a formula (7), a formula (8) and a formula (9).
Average wheel speed for M-1 cycle:
Va(M-1) =(Va(M-3)+Va(M-2)+Vt(M-1))/3;(6)
Average wheel speed for the M-th cycle:
Va(M) =(Va(M-2)+Va(M-1)+Vt(M))/3;(7)
Wheel deceleration in the M-th cycle:
a(M)=(Va(M) - Va(M-1))/;(8)
wheel deceleration rate of change in the M-th period:
=|(a(M)-a(M-1))|/。(9)
Wherein Vt (M) represents a wheel speed signal of an M-th period, vt (M-1) represents a wheel speed signal of an M-1-th period, va (M-3) represents an average wheel speed of an M-3-th period, va (M-2) represents an average wheel speed of an M-2-th period, va (M-1) represents an average wheel speed corresponding to an M-1-th period, va (M) represents an average wheel speed corresponding to an M-th period, a (M) represents a wheel deceleration corresponding to an M-th period, and a (M-1) represents a wheel deceleration corresponding to an M-1-th period; the wheel deceleration change rate corresponding to the M-th cycle is shown.
Further, when the wheel deceleration of the wheels has deceleration, the wheel deceleration range should be controlled so as not to exceed the deceleration threshold value #) If the deceleration threshold is exceeded, wheel lock may occur and the wheel will lose lateral force, resulting in vehicle instability.The parameter setting is completed through the whole vehicle calibration, and the common wheel slip rate is determined by 15%. When the wheel deceleration exceeds the deceleration thresholdThe wheel side controller releases the target clamping force when the wheel deceleration falls back toAnd then, the wheel side controller reappears the target clamping force, so that the wheel can keep rotating, and stable braking is realized.
Exemplary, as shown in FIG. 4, where the vertical axis is acceleration, the dashed line represents the target deceleration after the vehicle begins to decelerate, the curved line represents the actual deceleration of the vehicle during braking, and the range of wheel deceleration exceeds the deceleration threshold at S1) In order to prevent the vehicle from locking or other conditions, the hub controller releases the target clamping force at S1 to enable the wheels to return to normal rotation, and when the wheel deceleration of the vehicle returns to S2The wheel side controller then reappears the target controller.
Further, the wheel deceleration change rate is used to determine the tendency of locking of the wheels in advance, and the target clamping force of the wheel rim is controlled in advance, so that the vehicle is prevented from losing stability. Threshold value of change rate) Parameter setting is required to be completed through whole vehicle calibration. When the change rate of the wheel deceleration exceeds the change rate threshold value) The wheel side controller releases the target clamping force. When the change rate of the wheel deceleration falls back toThe wheel side controller then reappears the target clamping force.
Exemplary, as shown in FIG. 5, the vertical axis is the rate of change of acceleration, and the rate of change of the vehicle ' S wheel deceleration exceeds the rate threshold at S1, i.e., the vehicle ' S speed decreases sharply, to avoid the occurrence of a sharp decrease in vehicle ' S speed, the wheel side controller releases the target clamping force at S1 and drops back to S2 at the rate of change of wheel decelerationThe wheel side controller then reappears the target clamping force.
Finally, the vehicle is braked and brought to a stopped state by slip rate control of the wheel deceleration and the wheel deceleration change rate. When the vehicle is stopped, the maintenance time is kept) The target clamping force is maintained, and the holding time can be adjusted according to the voltage condition of the vehicle, and the holding time is more than 10 minutes in an exemplary way.
In the embodiment of the application, the four wheel side controllers are controlled by adopting the braking control method, and simultaneously provide braking clamping force for longitudinal deceleration control of the vehicle, so that the vehicle can be stopped slowly, and the situation that the vehicle is out of control is avoided.
It is known that the wheel side controller in the embodiment of the application does not need to add more redundant communication buses, thereby saving the cost.
The embodiment of the application also provides a brake control system of the distributed brake system, which comprises the brake control method of the distributed brake system.
The application provides a braking control method and a braking control system of a distributed braking system, which realize safe braking of a vehicle through a wheel side controller when a high-speed bus in the distributed braking system fails, improve the safety and the robustness of the distributed braking system, control wheels through a target clamping force to realize safe braking at the minimum deceleration, ensure that the vehicle can still realize safe braking even if the high-speed bus fails to be controlled through a braking domain controller, improve the safety and the robustness of the system, furthest ensure that the vehicle can still stop braking when the distributed braking system fails, effectively shorten the influence time of the failure, ensure the operation safety of the vehicle, have stronger universality and expansibility, provide powerful support for maintenance and management, reduce the maintenance cost, and the wheel side controller does not need to increase more redundant communication buses, thereby saving the cost.
It will be apparent to those skilled in the art that various modifications and variations can be made to the present application without departing from the spirit or scope of the application. Thus, it is intended that the present application also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.
Claims (10)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202510048695.9A CN119428599A (en) | 2025-01-13 | 2025-01-13 | Brake control method and system of distributed brake system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202510048695.9A CN119428599A (en) | 2025-01-13 | 2025-01-13 | Brake control method and system of distributed brake system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN119428599A true CN119428599A (en) | 2025-02-14 |
Family
ID=94514900
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202510048695.9A Pending CN119428599A (en) | 2025-01-13 | 2025-01-13 | Brake control method and system of distributed brake system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN119428599A (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101062684A (en) * | 2006-04-28 | 2007-10-31 | 丰田自动车株式会社 | Vehicle control device, and method of controlling a vehicle |
| US20130245910A1 (en) * | 2010-11-25 | 2013-09-19 | Toyota Jidosha Kabushiki Kaisha | Brake force control apparatus for vehicle and brake force control method for vehicle |
| CN106985810A (en) * | 2015-12-08 | 2017-07-28 | 福特全球技术公司 | Vehicle deceleration is determined |
| CN110709296A (en) * | 2017-06-12 | 2020-01-17 | 罗伯特·博世有限公司 | Method and control device for carrying out emergency and/or panic braking of a vehicle |
| CN117901832A (en) * | 2022-10-18 | 2024-04-19 | 通用汽车环球科技运作有限责任公司 | Differential braking and yaw rate mitigation in deceleration-increasing brake-by-wire events during a fault event |
| CN118810724A (en) * | 2024-07-31 | 2024-10-22 | 岚图汽车科技有限公司 | Electronic brake system control method, device, and readable storage medium |
-
2025
- 2025-01-13 CN CN202510048695.9A patent/CN119428599A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101062684A (en) * | 2006-04-28 | 2007-10-31 | 丰田自动车株式会社 | Vehicle control device, and method of controlling a vehicle |
| US20130245910A1 (en) * | 2010-11-25 | 2013-09-19 | Toyota Jidosha Kabushiki Kaisha | Brake force control apparatus for vehicle and brake force control method for vehicle |
| CN106985810A (en) * | 2015-12-08 | 2017-07-28 | 福特全球技术公司 | Vehicle deceleration is determined |
| CN110709296A (en) * | 2017-06-12 | 2020-01-17 | 罗伯特·博世有限公司 | Method and control device for carrying out emergency and/or panic braking of a vehicle |
| CN117901832A (en) * | 2022-10-18 | 2024-04-19 | 通用汽车环球科技运作有限责任公司 | Differential braking and yaw rate mitigation in deceleration-increasing brake-by-wire events during a fault event |
| CN118810724A (en) * | 2024-07-31 | 2024-10-22 | 岚图汽车科技有限公司 | Electronic brake system control method, device, and readable storage medium |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8442737B2 (en) | Method for operating a vehicle brake system and vehicle brake system | |
| EP2760714B1 (en) | Slip-controlled braking system for electrically driven motor vehicles | |
| CN106427601B (en) | The braking system and method and electric car of electric car based on four-wheel drive | |
| EP1638826B1 (en) | Brake system for a railway vehicle with digital databus | |
| US10000194B2 (en) | Method, controller and system for monitoring brake operation | |
| US9073524B2 (en) | Braking system and method for a towed vehicle | |
| CN108025651A (en) | Electric vehicle with the braking system and method for braking system, controller and computer program | |
| JP2004231168A (en) | Method and apparatus for monitoring overload of vehicle brake of electronically controlled braking system for vehicle or combined vehicles | |
| AU2013292777A1 (en) | Method for braking a combination of a plurality of vehicles coupled to one another | |
| CN102848926B (en) | Anti-lock control method for vehicle braked by eddy current retarder and main brake together | |
| CN119428599A (en) | Brake control method and system of distributed brake system | |
| CN116691685A (en) | Method and device for controlling single-point braking failure vehicle and vehicle | |
| CN116533955A (en) | Vehicle braking control method and device and vehicle | |
| CN117864079A (en) | Distributed control system, motor vehicle braking system and motor vehicle | |
| US11142177B2 (en) | Method for adjusting brake pressures, brake system of a motor vehicle for carrying out such method, and motor vehicle comprising such a brake system | |
| US6431660B2 (en) | Method for automatically detecting the installation position of brake force generating units of an electromagnetic motor vehicle brake system | |
| US20210188098A1 (en) | System for an electrically driven vehicle, vehicle having same and method for same | |
| CN216734246U (en) | Double-control redundant brake-by-wire system | |
| CN217553891U (en) | Service brake failure auxiliary device | |
| CN114802201B (en) | Control method and device for improving driving safety of vehicle | |
| CN215634593U (en) | Novel brake temperature warning device | |
| CN115158276B (en) | Redundancy control method and redundancy control system for multi-brake system | |
| CN117681850A (en) | Brake-by-wire system, vehicle and control method for vehicle | |
| CN117246142A (en) | Braking method, braking system and vehicle | |
| CN111032454A (en) | Method/device for improving braking performance of wheeled vehicle |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |