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CN-121973739-A - Vehicle and method, device and medium for detecting pressure build-up capability of braking system of vehicle

CN121973739ACN 121973739 ACN121973739 ACN 121973739ACN-121973739-A

Abstract

The application relates to the technical field of vehicle braking and discloses a method, a device and a medium for detecting the build-up capacity of a vehicle and a braking system thereof, wherein the method is started when the whole vehicle finishes driving operation and enters a running state after power-down; after confirming that the brake pedal is in an inactive state based on a state signal and confirming that the main control unit has completed functional self-checking and has cooperative pressure build-up capability, based on ready state information, controlling the main control unit to establish reference pressure and collect a first pressure value, controlling the backup control unit to execute excitation action and collect a second pressure value, and determining a pressure build-up capability test result of the backup control unit based on the relation between the difference value between the first pressure value and the second pressure value and a preset pressure threshold value and the subsequent power supply state of the whole vehicle.

Inventors

  • LIU ZHIBO
  • LI WANCHENG
  • WU BIN

Assignees

  • 赛力斯汽车有限公司

Dates

Publication Date
20260505
Application Date
20260317

Claims (10)

  1. 1. A method for detecting a build-up capacity of a vehicle brake system, the brake system comprising a primary control unit and a backup control unit, the method comprising: After the whole vehicle is powered down and waiting for a first preset time, monitoring a state signal of a brake pedal in real time, and synchronously acquiring ready state information of the main control unit; After confirming that the brake pedal is in an inactive state based on the state signal and confirming that the main control unit has completed functional self-checking and has cooperative pressure build-up capability based on the ready state information, controlling the main control unit to build up reference pressure and collect a first pressure value, and controlling the backup control unit to execute excitation action and collect a second pressure value; and determining a voltage build-up capability test result of the backup control unit based on the relation between the difference value between the first pressure value and the second pressure value and a preset pressure threshold value and the subsequent power supply state of the whole vehicle.
  2. 2. The method of claim 1, further comprising performing a fault tolerance decision process when the brake pedal is not in an inactive state or the master control unit is not in a ready state; the fault tolerance judging process comprises the following steps: if the brake pedal is continuously in an activated state within a second preset time, calling an effective pressure build-up capacity judgment result in the previous driving cycle as a judgment basis; If the main control unit fails to reach the ready state within the third preset time, triggering reset and re-executing self-checking; If the ready state still cannot be reached after at least one reset self-check, calling an effective voltage build-up capacity judgment result in the previous driving cycle as a judgment basis; the second preset time is the longest allowed waiting time before the whole vehicle enters the sleep preparation stage, and the third preset time is the shortest reserved time required by guaranteeing the completion of reset and self-checking of the main control unit.
  3. 3. The method of claim 1, wherein determining the voltage build capability test result of the backup control unit based on the relationship between the difference between the first pressure value and the second pressure value and a preset pressure threshold, and the vehicle subsequent power state comprises: calculating a difference between the second pressure value and the first pressure value as a net boost value; if the net pressure increasing value is larger than or equal to the preset pressure threshold value, determining that the pressure building capability of the backup control unit is normal; if the net pressure increasing value is smaller than the preset pressure threshold value, executing a grading response flow; The hierarchical response flow includes: Recording an event of insufficient pressure build-up capability at one time, and marking the event as a first-stage failure record; if the whole vehicle is electrified again after the current power-down and all detection flows of the running state after the power-down are not completed, only updating the primary failure record; If the whole vehicle enters a thorough dormant state after the power-down, executing a complete pressure build-up capability verification process in the next power-up initialization stage; and when the execution fails, outputting a failure fault signal of the voltage building function of the backup control unit.
  4. 4. The method of claim 1, wherein the energizing acts as the backup control unit driving the motor to rotate a preset number of turns at a preset rotation rate.
  5. 5. The method of claim 1, wherein the predetermined pressure threshold is a minimum build-up pressure delta threshold required to ensure third-level autopilot functionality, the minimum build-up pressure delta threshold being determined based on hydraulic response characteristics of the brake system, line volume, actuator dynamic delay, and functional safety redundancy rating.
  6. 6. The method of claim 1, wherein the vehicle braking system includes four wheel cylinder inlet valves, two master cylinder isolation valves, two pressure build isolation valves, and two normally open valves and two normally closed valves integrated within a pressure build pump outlet valve block of the backup control unit; Before the control of the main control unit to establish the reference pressure and collect the first pressure value and the control of the backup control unit to execute the excitation action and collect the second pressure value, the method further comprises the steps of constructing a closed pressure cavity; the building of the closed pressure chamber comprises: the main control unit is controlled to close the four wheel cylinder liquid inlet valves, and open the two master cylinder isolation valves and the two pressure building isolation valves; Controlling the backup control unit to close the two normally open valves and the two normally closed valves; The main control unit and the valve body of the backup control unit are synchronously executed or cooperatively executed according to a preset time sequence.
  7. 7. The method of claim 2, wherein the vehicle follow-up power state comprises: the power-on is performed again after the power-off, but the running state after the power-off is not exited; entering a thorough dormancy state after the power-down; the power-on instruction is received during the running state after the power-off, so that the detection flow is stopped; during the running state after the power-down, the brake pedal is continuously in an activated state for more than the second preset time; When a power-on instruction is received during a power-off running state to stop a detection flow, the main control unit and the backup control unit are restored to a working state before power-off, the voltage build-up capacity judgment result is kept valid, and a new voltage build-up capacity detection flow is not triggered; and when the brake pedal is continuously in an activated state for more than the second preset time during the running state after the current power-down, calling an effective voltage build-up capacity judgment result in the previous driving cycle as a current judgment basis.
  8. 8. A build-up capability detection device for a vehicle brake system, the brake system comprising a primary control unit and a backup control unit, the device comprising: the state information acquisition module is used for monitoring a state signal of the brake pedal in real time after the first preset time is waited after the whole vehicle is powered down, and synchronously acquiring ready state information of the main control unit; The detection module is used for controlling the main control unit to establish reference pressure and collect a first pressure value and controlling the backup control unit to execute excitation action and collect a second pressure value after confirming that the brake pedal is in an inactive state based on the state signal and confirming that the main control unit has completed functional self-checking and has cooperative pressure build-up capability based on the ready state information; The detection module is used for determining a voltage build-up capability test result of the backup control unit based on the relation between the difference value between the first pressure value and the second pressure value and a preset pressure threshold value and the subsequent power supply state of the whole vehicle.
  9. 9. A vehicle, characterized in that the vehicle comprises a processor and a memory, the memory storing a computer program, the processor being adapted to execute the computer program to implement the build-up capability detection method of any one of claims 1-7.
  10. 10. A computer readable storage medium, characterized in that it stores a computer program which, when executed on a processor, implements the build-up capability detection method according to any one of claims 1-7.

Description

Vehicle and method, device and medium for detecting pressure build-up capability of braking system of vehicle Technical Field The present application relates to the field of vehicle braking technologies, and in particular, to a method, an apparatus, and a medium for detecting a pressure build-up capability of a vehicle and a braking system thereof. Background When the existing vehicle braking system detects the pressure build-up capability of the backup control unit, a single pressure test mode is generally adopted after power-down, namely, the detection is started immediately after the whole vehicle is flameout, and whether the pressure build-up capability is normal is judged only according to whether the pressure value measured once reaches a threshold value or not. According to the method, the actual working conditions such as operation residues of a driver (such as incomplete return of a pedal), self-checking delay of a main control unit, accidental power-on or dormancy of the vehicle in the detection process and the like are not considered, so that the detection result is easy to interfere, and the misjudgment rate is high. And once the judgment fails, the feedback backup system is abnormal in function, the third-level automatic driving function is directly disabled, and the normal use experience and the system reliability of the user are seriously affected. Disclosure of Invention In view of the above, the embodiments of the present application provide a method, an apparatus, and a medium for detecting a build-up capability of a vehicle and a braking system thereof, which can implement multi-condition collaborative determination, closed pressure environment construction, synchronous reference and excitation pressure acquisition, and dynamic build-up capability determination that fuses power behaviors, so as to improve reliability and user availability of backup braking system detection on the premise of ensuring safety of a third-stage autopilot function. In a first aspect, an embodiment of the present application provides a method for detecting a build-up capability of a vehicle brake system, where the brake system includes a main control unit and a backup control unit, the method includes: After the whole vehicle is powered down and waiting for a first preset time, monitoring a state signal of a brake pedal in real time, and synchronously acquiring ready state information of the main control unit; After confirming that the brake pedal is in an inactive state based on the state signal and confirming that the main control unit has completed functional self-checking and has cooperative pressure build-up capability based on the ready state information, controlling the main control unit to build up reference pressure and collect a first pressure value, and controlling the backup control unit to execute excitation action and collect a second pressure value; and determining a voltage build-up capability test result of the backup control unit based on the relation between the difference value between the first pressure value and the second pressure value and a preset pressure threshold value and the subsequent power supply state of the whole vehicle. In an alternative embodiment, the method further comprises the step of executing a fault tolerance judging process when the brake pedal is not in an inactive state or the main control unit is not in a ready state; the fault tolerance judging process comprises the following steps: if the brake pedal is continuously in an activated state within a second preset time, calling an effective pressure build-up capacity judgment result in the previous driving cycle as a judgment basis; If the main control unit fails to reach the ready state within the third preset time, triggering reset and re-executing self-checking; If the ready state still cannot be reached after at least one reset self-check, calling an effective voltage build-up capacity judgment result in the previous driving cycle as a judgment basis; the second preset time is the longest allowed waiting time before the whole vehicle enters the sleep preparation stage, and the third preset time is the shortest reserved time required by guaranteeing the completion of reset and self-checking of the main control unit. In an optional implementation manner, the determining the voltage build-up capability test result of the backup control unit based on the relationship between the difference value between the first pressure value and the second pressure value and the preset pressure threshold value and the subsequent power supply state of the whole vehicle includes: calculating a difference between the second pressure value and the first pressure value as a net boost value; if the net pressure increasing value is larger than or equal to the preset pressure threshold value, determining that the pressure building capability of the backup control unit is normal; if the net pressure increasing value is smaller than the pre