A wire-control interaction method to avoid chassis brake actuator failure

Abstract

The present invention provides a wire-controlled interactive method for preventing chassis brake actuator failure, comprising the following steps: constructing a wire-controlled interactive system suitable for autonomous vehicles, wherein the system utilizes wire-controlled signals for interactive operations and comprises at least a sensor, an autonomous driving central processing unit (CPU), a brake controller, and a brake actuator; the sensor is used to monitor and transmit the brake actuator status to the CPU; the CPU sends a control signal to the brake controller based on the brake actuator status and vehicle information; the brake controller generates an instruction based on the control signal and transmits the instruction to the brake actuator; the brake actuator executes the corresponding braking action based on the instruction; and when an abnormal operating condition is detected, taking action based on an emergency response strategy. The present invention can reduce the risk of brake actuator failure in autonomous vehicles and improve driving stability and safety.

Description

Technical Field

[0001] The present invention relates to the automotive field, and in particular to a wire control interaction method for avoiding failure of a chassis brake actuator. Background Art

[0002] Autonomous vehicles are intelligent vehicles that achieve partial or full autonomy through sensors, controllers, and other equipment. Chassis brake actuators are key components of autonomous vehicles, and their performance, stability, and reliability are directly related to vehicle safety. However, over extended periods of operation, chassis brake actuators can be affected by factors such as wear, overload, and thermal fatigue, leading to performance degradation or even failure. This not only impacts vehicle operation but also increases the risk of traffic accidents.

[0003] Existing strategies and methods for preventing chassis brake actuator failure in autonomous vehicles primarily include regular maintenance, condition monitoring, and fault prediction. Regular maintenance prevents failures by regularly inspecting and replacing brake actuator components. Condition monitoring uses sensors to monitor the operating status of chassis actuators and take timely action when anomalies are detected. Fault prediction analyzes chassis actuator operating data to predict potential failures and take proactive action.

[0004] However, these strategies and methods all have limitations. While regular maintenance can prevent failures, it requires regular inspection and replacement of parts, increasing maintenance costs. Condition monitoring can promptly detect anomalies, but it can also lead to monitoring system failures or false alarms. Fault prediction can anticipate potential failures, but it also requires proactive action, which can lead to inaccurate predictions and ineffective measures. Currently, autonomous vehicles typically operate 24 / 7, and their by-wire chassis brake actuators operate 24 / 7. Autonomous driving systems can meet virtually all operating scenarios, all of which rely on the by-wire chassis brake actuators. When an autonomous vehicle encounters traffic jams, traffic light anomalies, or an obstacle blocking the way, forcing it to wait in place, the by-wire chassis of the autonomous driving system typically applies a certain deceleration to maintain the brakes in place. This maintains a constant pressure on the chassis brake actuator, which remains in operation for extended periods. This can be affected by factors such as wear, overload, and thermal fatigue, leading to degraded performance or even failure, causing the vehicle to brake improperly or roll away, potentially causing traffic accidents. Summary of the Invention

[0005] In response to the defects in the prior art, the purpose of the present invention is to provide a wire-controlled interaction method to avoid failure of the chassis brake actuator, reduce the risk of brake actuator failure of autonomous driving vehicles, and improve driving stability and driving safety.

[0006] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical solution:

[0007] The present invention provides a wire control interaction method for preventing chassis brake actuator failure, comprising the following steps:

[0008] Constructing a control-by-wire interactive system for autonomous vehicles, the system uses control-by-wire signals for interactive operations and includes at least a sensor, an autonomous driving central processing unit (CPU), a brake controller, and a brake actuator. The sensor is used to monitor and transmit the brake actuator status to the CPU.

[0009] The autonomous driving central processor sends control signals to the brake controller based on the brake actuator status and vehicle information;

[0010] The brake controller generates a command based on the control signal and transmits the command to the brake actuator;

[0011] The brake actuator performs the corresponding braking action according to the instruction;

[0012] When an abnormal operating condition is detected, treatment measures are taken according to the emergency treatment strategy, which includes:

[0013] When a brake controller failure is detected, the brake controller sends an ESC fault signal and requests parking. The autonomous driving central processor simultaneously requests parking upon receiving the ESC fault signal.

[0014] A communication loss condition with the brake controller is detected and the autonomous driving central processor requests parking.

[0015] When the vehicle is detected to be in motion and the communication with the autonomous driving central processor is lost, the brake controller commands the vehicle to brake until the speed drops to 0, requesting parking.

[0016] Preferably, when manual intervention is detected in the automatic driving mode, the brake controller will suspend entering the automatic driving until the manual intervention is eliminated.

[0017] Preferably, the processing measures further include providing feedback prompts to the driver.

[0018] Preferably, the brake controller is pre-set with a first pressure holding time, and the brake controller requests parking before the first pressure holding time.

[0019] Preferably, the brake controller is also preset with a second pressure holding time, and will request parking and release pressure before the second pressure holding time, and the second pressure holding time is greater than the first pressure holding time.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] By real-time monitoring and dynamic adjustment of chassis control logic, the present invention effectively reduces the risk of chassis actuator failure in autonomous commercial vehicles, improves the vehicle's response speed and stability, and further enhances the safety of autonomous commercial vehicles. At the same time, it has high adaptability and scalability, and can adapt to different types of chassis actuators and different application scenarios of autonomous commercial vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0023] Figure 1 Schematic diagram of the process described in the embodiment. DETAILED DESCRIPTION

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Generally, the components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0025] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for protection, but merely represents selected embodiments of the present application. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments in the present application without creative work are within the scope of protection of the present application.

[0026] It should be noted that similar numbers and letters represent similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined or explained in subsequent figures. In addition, all directional indications in this application (such as up, down, left, right, front, back, bottom...) are only used to explain the relative position relationship, movement, etc. between the components under a specific posture (as shown in the figures). If the specific posture changes, the directional indication will also change accordingly. Furthermore, the descriptions of "first", "second", etc. in the application are for descriptive purposes only and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features.

[0027] Example

[0028] The present invention provides a wire control interaction method to avoid chassis brake actuator failure, such as Figure 1 As shown, the following steps are included:

[0029] In step S1, a drive-by-wire interaction system for an autonomous vehicle is constructed. The system uses drive-by-wire signals for interactive operations. Specifically, the system includes at least sensors, an autonomous driving central processing unit (ADCU), an electric brake controller (ESC), and a brake actuator. The sensors monitor the brake actuator status, including brake disc speed, temperature, and brake disc wear, and transmit the status data to the autonomous driving central processing unit.

[0030] In step S2, the autonomous driving central processor sends a control signal to the brake controller based on the brake actuator status and vehicle information. The specific logical interaction principle is explained below:

[0031] Under normal operating conditions, when the ESC determines it can release control to the ADCU, the ESC control state is 0x1, which is the normal state. When the ADCU determines the ESC control state is 0x1, it sends an enable signal (ENABLE). The ESC then responds with a signal of 0x2, entering autonomous driving mode. The ADCU sends a signal of 0x2, indicating autonomous driving mode. The ESC decides whether to accept the ADCU signal (0x2) based on a pre-set strategy. The ADCU also requests a deceleration value based on driving conditions until it is time to exit autonomous driving. At this point, the ADCU sends a signal of DISABLE, disabling the ESC and returning the ESC control state to 0x1, indicating controllable mode. In autonomous driving mode, the ESC also exits autonomous driving upon receiving a signal (0x3) from the ADCU requesting it to exit autonomous driving, returning the ESC control state to 0x1, indicating controllable mode. In autonomous driving mode, if an ESC fault occurs, it issues a fault signal, causing the ESC control state to change from 0x2 to 0x3, permanently preventing autonomous driving from being entered until the fault is resolved and the ESC returns to 0x1.

[0032] In step S3, the brake controller generates a command based on the control signal and transmits the command to the brake actuator. Specifically, this embodiment adopts a standstill signal design, specifically: the ESC determines whether to maintain pressure based only on the standstill signal. When standstill = 0, the ESC does not maintain pressure, and when standstill = 1, the ESC maintains pressure.

[0033] Preferably, in autonomous driving mode, when manual intervention is detected, the ESC will suspend autonomous driving until the manual intervention is eliminated. For example, when the ESC detects that the driver has stepped on the brakes, it will send a manual intervention signal, and the ESC control state will change from 0x2 to 0x0, temporarily preventing the vehicle from entering autonomous driving. After the brakes are released, the ESC control state will return to 0x1, a controllable state, implementing the principle of manual priority and giving priority to responding to manual intervention.

[0034] In step S4 , the brake actuator performs corresponding braking actions according to the instruction, such as clamping and releasing the brake disc.

[0035] In step S5, a fault monitoring and early warning mechanism is established to monitor the operating status of the brake actuator in real time. When an abnormal operating condition is detected, emergency response measures are taken according to the emergency response strategy. The response measures may include switching to a backup redundant braking device, reducing the vehicle's speed, or pulling over safely and reporting to the maintenance system. Preferably, the response measures also include providing feedback to the driver to help the driver promptly understand the operating status of the brake actuator. Specifically, the emergency response strategy includes:

[0036] If the ESC fails in automatic driving mode, the ESC will send an ESC fault signal and request EPB to park. At the same time, the ADCU will read the ESC fault signal and request EPB (electronic parking system) to park. If the ESC fails in manual driving mode, the ESC will not take action and the driver will be responsible for manually engaging the EPB.

[0037] If ESC communication is lost, the ADCU requests the EPB to park the vehicle.

[0038] If ADCU communication is lost when the vehicle is in motion, ESC controls the brakes until the vehicle speed drops to 0 and requests EPB to park. When ADCU communication is lost (more than 10 frames), the ESC controlled state changes from 0X2 to 0x1, and ESC brakes to 0 to request EPB to park and wait for the next request from ADCU. When the vehicle is stationary, this operation is not performed because the EPB takes over directly.

[0039] The methods provided in this embodiment all utilize wire-controlled signals for interactive operation, enabling real-time monitoring of the brake actuator's status and adjusting the control signals as needed to ensure stable operation of the brake actuator. Furthermore, by incorporating fault monitoring and early warning mechanisms, abnormalities can be promptly detected and appropriate remedial measures implemented, thereby preventing brake actuator failure.

[0040] The following describes the operating logic of the method provided in this embodiment during normal driving and temporary stops. When the vehicle speed is greater than a first preset speed, for example, 3 kilometers per hour, the ADCU requests a deceleration value, and the ESC responds to the ADCU's request. When the speed is less than or equal to the first preset speed, the ADCU requests a deceleration value, and the ESC first responds to the deceleration value. The deceleration pressure value is maintained until the ESC loses the speed.

[0041] The following describes the operational logic of the method provided by this embodiment in a permanent parking condition. First, the vehicle speed is compared with a second preset speed, for example, 3 kilometers per hour. If the vehicle speed is greater than 3 kilometers per hour, the ADCU requests a deceleration value, and the ESC responds based on the requested deceleration. If the speed is less than 3 kilometers per hour, the ADCU requests a deceleration value, and the ESC first responds to the deceleration value. The original deceleration pressure value is maintained until the ESC cannot obtain the speed. When the ADCU determines that the vehicle speed is equal to 0, it requests STANDSTILL = 1, and the ESC maintains pressure. The ADCU then requests EPB parking. Once EPB parking is complete, the ADCU requests a deceleration of 0 and standstill = 0 to release the brakes, and the ESC releases pressure.

[0042] Preferably, a first dwell time is preset for the ESC, and the ESC requests EPB parking before the first dwell time. For example, the preset maximum dwell time is 30 seconds, and the ESC can request EPB parking at the 25th second, after which the ESC releases pressure. Preferably, an ESC self-protection mechanism is provided as a redundant protection mechanism, that is, the ESC has a second dwell time when responding to a deceleration request, and will request parking and release pressure before the second dwell time. The second dwell time is greater than the first dwell time. For example, if the ESC second dwell time is 60 seconds, it will request parking at 55 seconds, release pressure, and the controlled state will change to 0x0. After 5 seconds, the controllable state will be restored, and another 60-second cycle will be executed, continuing to respond to the previous deceleration value.

[0043] The above describes the specific embodiments of the present invention. Based on the above description, relevant personnel can make various changes and modifications without departing from the scope of the technical concept of this invention.

Claims

1. A wire control interaction method for avoiding chassis brake actuator failure, characterized in that: The following steps are included: Constructing a control-by-wire interactive system for autonomous vehicles, the system uses control-by-wire signals for interactive operations and includes at least a sensor, an autonomous driving central processing unit (CPU), a brake controller, and a brake actuator. The sensor is used to monitor and transmit the brake actuator status to the CPU. The autonomous driving central processor sends control signals to the brake controller based on the brake actuator status and vehicle information; The brake controller generates a command based on the control signal and transmits the command to the brake actuator; The brake actuator performs the corresponding braking action according to the instruction; When an abnormal operating condition is detected, treatment measures are taken according to the emergency treatment strategy, which includes: When a brake controller failure is detected, the brake controller sends an ESC fault signal and requests parking. The autonomous driving central processor simultaneously requests parking upon receiving the ESC fault signal. A communication loss condition with the brake controller is detected and the autonomous driving central processor requests parking. When the vehicle is detected to be in motion and the communication with the autonomous driving central processor is lost, the brake controller commands the vehicle to brake until the speed drops to 0, requesting parking.

2. The wire control interaction method for avoiding chassis brake actuator failure according to claim 1, characterized in that: When manual intervention is detected in autonomous driving mode, the brake controller will suspend entering autonomous driving until the manual intervention is eliminated.

3. The wire control interaction method for avoiding chassis brake actuator failure according to claim 1, characterized in that: The processing measures also include providing feedback prompts to the driver.

4. The wire control interaction method for avoiding chassis brake actuator failure according to claim 1, characterized in that: The brake controller is preset with a first pressure holding time, and the brake controller requests parking before the first pressure holding time.

5. The wire control interaction method for avoiding chassis brake actuator failure according to claim 4, characterized in that: The brake controller is also preset with a second pressure holding time, and will request parking and release pressure before the second pressure holding time, and the second pressure holding time is greater than the first pressure holding time.

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