Decoupling type brake-by-wire control system

Abstract

The invention belongs to the technical field of automobile braking, and discloses a decoupling type brake-by-wire control system which comprises a brake-by-wire pedal, an electric control power-assisted control system, an automobile body stability control system and a whole automobile controller. The brake-by-wire pedal has two paths of independent output, and each path of output comprises two paths of displacement; the electric control power-assisted control system receives a first path of displacement signal output by the brake-by-wire pedal and implements brake power-assisted; the vehicle body stability control system is used for realizing stability control; the brake-by-wire pedal is used as a backup service brake after the electronic control power-assisted control system fails, and receives a second signal output by the brake-by-wire pedal; and the vehicle control unit controls the brake-by-wire pedal, the electric control power-assisted control system and the vehicle body stability control system respectively. The requirement of an intelligent driving system for actuator components is met, and necessary guarantee is provided for the safety of the whole vehicle.

Description

Technical Field

[0001] The invention relates to the technical field of automobile braking, and in particular to a decoupled brake-by-wire control system. Background Art

[0002] The automobile braking system plays a vital role in the safe driving of the vehicle. The use of wire control technology to build an electronic control system related to automobile safety performance can greatly improve the safety, reliability and stability of driving. Wire control braking has brought fundamental changes to the structure and braking performance of the vehicle, and has incomparable advantages over traditional braking systems.

[0003] For new energy electric vehicles, the mainstream electric vehicles currently use the ONE-BOX solution (collectively referred to as the intelligent brake system) in the braking system. This solution is generally through the mechanical connection between the brake pedal and the ONE-BOX. The driver's pedal force does not act on the master cylinder, and the pedal feel is achieved through the simulator. The wire control brake system is a system in which the mechanical connection is gradually reduced, the power transmission between the brake pedal and the brake is separated, and replaced by a wire connection; the original brake pedal is replaced by a simulation generator, and the brake pedal position sensor is used to monitor the driver's braking intention to generate and transmit the brake signal, and the brake pedal mechanical signal is converted into an electric control signal, and the signal is transmitted to the control system and the actuator, and the braking force is realized by the electronic control module, and the pedaling feeling is simulated according to a certain algorithm. Feedback to the driver; the wire transmits energy and the data line transmits signals, so this type of braking is called wire control braking. If the brake pedal is only connected to a brake pedal position sensor, and there is no rigid connection or hydraulic connection between the pedal and the braking system, it can be regarded as a wire control brake system.

[0004] The safety of the braking system is very important to the safety of the entire vehicle. After the conventional brake fails, the backup of the braking system or related strategies are very important to the safety of the entire vehicle. We can understand the backup of the braking system as a downgrade strategy after the braking system fails. The downgrade strategy of the braking system is to ensure that the driver can still decelerate the vehicle to stop after the braking system fails, thereby ensuring the safety of the entire vehicle and the driver. Especially for the development of L3 and above autonomous driving, the redundancy of the braking system is a very important technical requirement.

[0005] The existing ONE-BOX or TWO-BOX solutions are still mechanically connected, and the brake pedal and BOX connection occupy a large space, which is not very conducive to the current pursuit of large internal space. In addition, mechanical connections will cause noise and vibration, which is not very conducive to the collision safety of the entire vehicle. Wire control braking can change all this and simplify vehicle production and processes. Summary of the invention

[0006] The purpose of the present invention is to provide a decoupled wire-controlled brake control system to solve the technical problems that the brake pedal must be physically connected to the electric booster, and the displacement signal of the brake pedal, the power supply of the electric booster, the wheel speed sensor, the communication, etc. are still single signal inputs.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] A decoupled brake-by-wire control system, comprising: a brake-by-wire pedal, an electric power-assist control system, a vehicle body stability control system and a vehicle controller;

[0009] The brake-by-wire pedal has two independent outputs, each of which contains two displacements;

[0010] The electronically controlled power-assisting control system receives a first displacement signal output by the wire-controlled brake pedal and implements brake assist;

[0011] The vehicle body stability control system realizes stability control; serves as a backup for service braking after the electronically controlled power-assisted control system fails, and receives a second signal output by the wire-controlled brake pedal;

[0012] The vehicle controller controls the brake-by-wire pedal, the electric power-assist control system and the vehicle stability control system respectively.

[0013] Preferably, it also includes: a wheel speed sensor; the body stability control system receives the wheel speed information of the wheel speed sensor and implements body stability control; the electronic power steering control system receives the wheel speed information of the wheel speed sensor, and when the body stability control system fails and it is detected that the wheel has a tendency to lock, implements backup anti-lock control.

[0014] Preferably, it also includes: basic braking; the electronic power-assisted control system and the vehicle body stability control system respectively control the basic braking.

[0015] Preferably, the basic brake includes: a caliper and a brake disc; the electronic power-assisted control system controls the caliper on one side, and the vehicle body stability control system controls the caliper on the other side.

[0016] Preferably, the electronically controlled power-assisting control system preferentially performs the service braking function and receives the brake-by-wire pedal displacement signal; after the electronically controlled power-assisting control system fails, the vehicle body stability control system performs the service braking function.

[0017] Preferably, the electronic power-assisted control system preferentially executes stability control related functions; after the vehicle body stability control system fails, the electronic power-assisted control system executes longitudinal control.

[0018] Beneficial effects of the present invention: The decoupled brake-by-wire control system of the present invention can meet the requirements of the intelligent driving system for actuator components and provide necessary guarantees for the safety of the entire vehicle. Since the brake-by-wire pedal is relatively small, it can provide more internal space; at the same time, the brake pedal feel is the same. It also brings relatively excellent noise, vibration and better safety collision effects for the entire vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0020] Figure 1 The invention relates to a decoupled brake-by-wire control system. DETAILED DESCRIPTION

[0021] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0022] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0023] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0024] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0025] 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 intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0026] like Figure 1As shown, the present invention provides a decoupled brake-by-wire control system, including: a brake-by-wire pedal (e-pedal), an electronically controlled power-assistance control system (EHBM), a vehicle stability control system (ESC), a wheel speed sensor (WSS), a basic brake and a vehicle control unit (VCU); the brake-by-wire pedal (e-pedal) has two independent outputs, each of which includes two displacements, namely, e-pedal1 and e-pedal2; the electronically controlled power-assistance control system (EHBM) receives a first displacement signal (e-pedal1) output by the brake-by-wire pedal (e-pedal), and implements Brake assist; ESC implements stability control; and serves as a backup for driving brakes after the EHBM fails, and receives the second signal (e-pedal2) output by the e-pedal; ESC receives wheel speed information from the WSS and implements body stability control; EHBM receives wheel speed information from the WSS and implements backup anti-lock control when the ESC fails and the wheels are detected to have a tendency to lock. EHBM and ESC control basic brakes respectively. Basic brakes include calipers and brake discs; EHBM controls the caliper on one side, and ESC controls the caliper on the other side. The electronic power steering control system (EHBM) gives priority to the service braking function and receives the displacement signal of the brake-by-wire pedal (e-pedal); after the electronic power steering control system (EHBM) fails, the body stability control system (ESC) performs the service braking function. The electronic power steering control system (EHBM) gives priority to the stability control related functions; after the body stability control system (ESC) fails, the electronic power steering control system (EHBM) performs longitudinal control. The vehicle control unit (VCU) controls the brake-by-wire pedal (e-pedal), the electronic power steering control system (EHBM) and the body stability control system (ESC) respectively.

[0027] During normal operation, the electronic power steering control system (EHBM) receives the e-pedal1 signal and the e-pedal2 signal forwarded by the body stability control system (ESC) to determine the driver's intention and implement service braking to achieve the normal basic power steering function of the braking system.

[0028] The vehicle stability control system (ESC) arbitrates whether to implement service braking through the power assist status of the electronic power assist control system (EHBM) or its communication status, and determines the driver's intention based on the e-pedal2 signal to implement backup power assist. At the same time, it receives wheel speed signal 2 and other IMU\EPS signals to implement vehicle stability control.

[0029] The electronic power steering control system (EHBM) receives the wheel speed signal 1 and implements backup anti-lock control when the vehicle stability control system (ESC) fails and a wheel locking tendency is detected.

[0030] For parking function, the electronic power steering control system (EHBM) controls the caliper on one side, and the body stability control system (ESC) controls the caliper on the other side to achieve redundant parking backup.

[0031] Failure mode: The electronic power steering control system (EHBM) prioritizes the service braking function and receives the e-pedal displacement signal; after the electronic power steering control system (EHBM) fails, the body stability control system (ESC) performs the service braking function; the body stability control system (ESC) prioritizes the stability control related functions; after the body stability control system (ESC) fails, the electronic power steering control system (EHBM) performs longitudinal control.

[0032] 1) When the power supply Battery1 has a power supply problem (overvoltage, undervoltage), the electronic power steering control system (EHBM) loses its power assist function, and the external failure state or no network signal is sent out, the body stability control system (ESC) actively identifies the failure state of the electronic power steering control system (EHBM) or the communication state, arbitrates whether to intervene in the power assist, and enters the service brake through the e-pedal2 signal. At the same time, the vehicle control unit (VCU) can intervene in the braking through energy recovery.

[0033] 2) When the power supply Battery2 has a power supply problem (overvoltage, undervoltage), the vehicle stability control system (ESC) loses all functions, and the external failure state or there is no network signal to send externally, and the electronic power steering control system (EHBM) still implements the service brake.

[0034] 3) When e-pedal1 appears:

[0035] The signal function is lost, no signal is sent out, and the electronic power steering control system (EHBM) cannot receive the displacement signal. The electronic power steering control system (EHBM) receives the e-pedal2 signal forwarded from the vehicle stability control system (ESC) to implement service braking;

[0036] The sent signal is too large, resulting in excessive brake assistance, so e-pedal1 is required to have two signals to verify each other;

[0037] The signal sent is too small, resulting in too little brake assistance. The electronic power assistance control system (EHBM) receives the e-pedal2 signal and implements the logic of "taking the larger" between e-pedal1 and e-pedal2;

[0038] If the signal is stuck at a fixed value, the brake assist is too small, and the brake assist is too large. If it is stuck at a too large value, it will be over-braked; if it is stuck at a too small value, there will be no harm to the vehicle.

[0039] There is a delay in sending signals and a slow brake response. e-pedal2 is needed to ensure normal signal transmission.

[0040] 4) When e-pedal2 appears:

[0041] The signal function is lost, no signal is sent out, and the electronic power steering control system (EHBM) cannot receive the displacement signal. The electronic power steering control system (EHBM) receives the e-pedal1 signal forwarded from the vehicle stability control system (ESC) to implement service braking;

[0042] The sent signal is too large, resulting in excessive brake assistance, so e-pedal1 is required to have two signals to verify each other;

[0043] The signal sent is too small, resulting in too little brake assistance. The electronic power assistance control system (EHBM) receives the e-pedal2 signal and needs to implement the logic of "taking the larger" between e-pedal1 and e-pedal2;

[0044] If the signal is stuck at a fixed value, the brake assist is too small, and the brake assist is too large. If it is stuck at a too large value, it will be over-braked; if it is stuck at a too small value, there will be no harm to the vehicle.

[0045] There is a delay in sending signals and a slow brake response. e-pedal2 is needed to ensure normal signal transmission.

[0046] 5) When wheel speed signal 1 appears:

[0047] Function lost, no signal, redundant backup ABS function lost, basic stability control function of the vehicle stability control system (ESC) is normal, and the system is risk-free;

[0048] The wheel speed signal is too large, the redundant backup ABS function is abnormal, and the electronic power steering control system (EHBM) needs to be identified and diagnosed, and a fault is reported;

[0049] The wheel speed signal is too small, the redundant backup ABS function is abnormal, and the electronic power steering control system (EHBM) needs to be identified and diagnosed, and a fault is reported;

[0050] The wheel speed signal is stuck, the redundant backup ABS function is abnormal, and the electronic power steering control system (EHBM) needs to be identified and diagnosed to report a fault.

[0051] 6) When wheel speed signal 2 appears:

[0052] Function loss, no signal, TCS, VDC, ABS downgraded to redundant backup ABS of the electronic power steering control system (EHBM), low selection logic;

[0053] The wheel speed signal is too large, affecting the dynamic functions of all vehicle stability control systems (ESC), and the electronic power steering control system (EHBM) needs to be identified and diagnosed;

[0054] The wheel speed signal is too small, which affects the dynamic functions of all vehicle stability control systems (ESC), and the electronic power steering control system (EHBM) needs to be identified and diagnosed;

[0055] The wheel speed signal is stuck, affecting the dynamic functions of all vehicle stability control systems (ESC), and the electronic power steering control system (EHBM) needs to be identified and diagnosed.

[0056] 7) When CANP loses communication, the electronic power steering control system (EHBM) and the vehicle stability control system (ESC) cannot communicate, and the status of each other is identified through CAN1 or CAN2. The electronic power steering control system (EHBM) still implements the service braking function.

[0057] 8) When CAN1 communication is lost, the service brake function of the electronic power steering control system (EHBM) is still normal.

[0058] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A decoupled brake-by-wire control system, characterized in that: include: Brake-by-wire pedal, electric power steering control system, body stability control system and vehicle controller; The brake-by-wire pedal has two independent outputs, each of which contains two displacements; The electronically controlled power-assisting control system receives a first displacement signal output by the wire-controlled brake pedal and implements brake assist; The vehicle body stability control system realizes stability control; serves as a backup for service braking after the electronically controlled power-assisted control system fails, and receives a second signal output by the wire-controlled brake pedal; The vehicle controller controls the brake-by-wire pedal, the electric power-assist control system and the vehicle stability control system respectively.

2. A decoupled brake-by-wire control system according to claim 1, characterized in that: Also includes: The vehicle body stability control system receives wheel speed information from the wheel speed sensor and implements vehicle body stability control; The electronic power-assisted control system receives wheel speed information from a wheel speed sensor, and implements backup anti-lock control when the vehicle body stability control system fails and a wheel locking tendency is detected.

3. The decoupled brake-by-wire control system according to claim 1, characterized in that: Also includes: Foundation brake; The electronic power-assist control system and the vehicle stability control system respectively control the foundation brake.

4. A decoupled brake-by-wire control system according to claim 3, characterized in that: The basic brake comprises: a caliper and a brake disc; the electronically controlled power-assisting control system controls the caliper on one side, and the vehicle body stability control system controls the caliper on the other side.

5. The decoupled brake-by-wire control system according to claim 1, characterized in that: The electronically controlled power-assisting control system preferentially performs the service braking function and receives the brake-by-wire pedal displacement signal; after the electronically controlled power-assisting control system fails, the vehicle body stability control system performs the service braking function.

6. The decoupled brake-by-wire control system according to claim 1, characterized in that: The electronic power-assisted control system preferentially executes stability control related functions; after the vehicle body stability control system fails, the electronic power-assisted control system executes longitudinal control.

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