Brake system function safety detection device and method

Abstract

The invention provides a braking system function safety detection device and method. The brake system function safety detection device comprises a fault injection device and a monitoring device. The fault injection device is connected between a brake control module of a vehicle and a whole vehicle network and used for conducting fault injection on a specific bus signal to form a fault signal and transmitting the fault signal between the brake control module and the whole vehicle network. The fault signal comprises a simulation receiving signal and a simulation sending signal, wherein the simulation receiving signal is used for simulating the brake control module to receive from the whole vehicle network, and the simulation sending signal is used for simulating the brake control module to send to the whole vehicle network. And the monitoring equipment is used for monitoring the braking system. The brake system is comprehensive and reliable in function safety detection and high in accuracy.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a braking system functional safety detection device and method. Background Art

[0002] The automobile brake control system is a key system assembly related to automobile braking safety and intelligent driving assistance. While the electronic and intelligent components of the brake system bring convenience and assistance to the driver, the harm caused by its failure to the driver, passengers and pedestrians is becoming more and more serious. Therefore, based on the design goal of system functional safety, how to reasonably and effectively use the necessary detection equipment to conduct test evaluation when the function fails is one of the key difficulties in research and development in the industry.

[0003] For the functional safety testing of the braking control system at the vehicle level, the commonly used method in the industry is to conduct actual vehicle verification by disconnecting the wiring harness plugs of sensors and switches, disconnecting the brake control module fuse in the relay box, and disconnecting the wiring harness plug of the brake control module installed in the front cabin. This is to check the actual performance of system functional degradation during such failures, that is, only functional safety analysis and testing of hard-wired faults and power supply fault conditions. However, the test scenario of this detection scheme cannot cover the working conditions when the communication signal of the vehicle network bus is abnormal, that is, it cannot simulate the fault of the communication signal of the brake control module, which has great limitations and further affects the braking safety during driving.

[0004] Therefore, it is necessary to provide an improved braking system functional safety detection device and method to solve the above problems. Summary of the invention

[0005] The present application provides a comprehensive, reliable and highly accurate braking system functional safety detection device and method.

[0006] The present application discloses a braking system functional safety detection device, including a fault injection device and a monitoring device.

[0007] The fault injection device is connected between the brake control module of the vehicle and the whole vehicle network, and is used to inject faults into a specific bus signal to form a fault signal, and transmit the fault signal between the brake control module and the whole vehicle network; the fault signal includes a simulated receiving signal received by the brake control module from the whole vehicle network and a simulated sending signal sent by the brake control module to the whole vehicle network;

[0008] The monitoring device is used to monitor the braking system.

[0009] Furthermore, the fault injection device includes a workstation, a first communication switching box and a fault test box which are connected in sequence, and the fault test box is connected between the brake control module and the vehicle network.

[0010] Furthermore, the fault test box is provided with an analog receiving interface connected to the brake control module and an analog sending interface connected to the whole vehicle network, the analog receiving interface sends the analog receiving signal to the brake control module, and the analog sending interface sends the analog sending signal to the whole vehicle network.

[0011] Furthermore, the monitoring device includes a second communication adapter box, and the second communication adapter box is respectively connected to the vehicle-mounted communication diagnostic system interface of the vehicle and the workstation.

[0012] Furthermore, the first communication adapter box is TC1034, the second communication adapter box is VN7640, and the workstation uses TSMaster software to edit the fault injection information of the specific bus signal.

[0013] Furthermore, the fault injection device is also used to inject hard-wire faults and power supply faults into the brake control module. The hard-wire faults include short circuits and open circuits of the communication harness; the power supply faults include power supply short circuits, power supply open circuits, excessive power supply voltage, and excessive power supply voltage.

[0014] Furthermore, the fault test box is provided with a plurality of switch interfaces, and a plurality of pins in the brake control module are respectively connected to the plurality of switch interfaces, and the plurality of switch interfaces are used to change the connection status of the plurality of pins to simulate the hard line fault and the power supply fault.

[0015] Furthermore, the analog received signal includes at least one of a steering wheel angle signal and an acceleration signal; the analog sent signal includes at least one of a wheel speed signal, a pedal travel signal, and a master cylinder pressure signal.

[0016] Furthermore, the types of fault injection of the specific bus signal include signal value injection faults, signal verification faults, and signal loss and jamming faults.

[0017] Furthermore, the signal value injection fault includes setting the specific bus signal to a fixed value, setting the specific bus signal offset, and setting the specific bus signal to be scaled proportionally; the signal verification type fault includes signal state validity error, cyclic redundancy check error, message count error, and verification error; the signal loss and jamming type fault includes signal loss and signal jamming.

[0018] The present application also discloses a brake system functional safety detection method, which is used for a vehicle equipped with a brake system functional safety detection device, wherein the brake system functional safety detection device includes a fault injection device and a monitoring device, and the method includes the following steps:

[0019] When the vehicle is running, a fault injection device is used to inject a fault into a specific bus signal to form a fault signal, and the fault signal is transmitted between the brake control module and the vehicle network; the fault signal includes a simulated receiving signal received by the simulated brake control module from the vehicle network and a simulated sending signal sent by the simulated brake control module to the vehicle network;

[0020] Obtain the monitoring results of the braking system by the monitoring equipment.

[0021] Furthermore, the monitoring results of the braking system by the monitoring device include: obtaining the time of function triggering or fault reporting after fault injection; obtaining the display of the brake system fault light of the instrument; obtaining the response of the brake pedal feeling; obtaining the vehicle body yaw angle; and obtaining the vehicle braking instantaneous deceleration.

[0022] The functional safety detection device and method of the brake system of the present application injects faults into a specific bus signal through a fault injection device to form a fault signal, and transmits the fault signal between the brake control module and the vehicle network, thereby simulating the communication fault between the brake control module and the vehicle network. The fault signal includes a simulated receiving signal received by the simulated brake control module from the vehicle network and a simulated sending signal sent by the simulated brake control module to the vehicle network. It can comprehensively evaluate the response capability of the brake control module to the data sent by the vehicle network and the effectiveness of the brake control module sending information to the vehicle network, and more accurately simulate, detect and analyze various fault situations, thereby improving the reliability and accuracy of detection.

[0023] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the specification and, together with the description, serve to explain the principles of the specification.

[0025] Figure 1 It is a schematic diagram of the connection between a braking system functional safety detection device and a vehicle according to an embodiment of the present application.

[0026] Figure 2 It is a flow chart of a braking system functional safety detection method according to an embodiment of the present application.

[0027] Figure 3 This is another flow chart of a braking system functional safety testing method according to an embodiment of the present application.

[0028] Description of Figure Numbers:

[0029] 10. Fault injection device; 11. Workstation; 12. First communication adapter box; 13. Fault test box; 131. Analog receiving interface; 132. Analog sending interface; 133. Switch interface; 20. Monitoring device; 30. Braking control module; 40. Vehicle network; 50. On-board communication diagnostic system interface. DETAILED DESCRIPTION

[0030] Here, the technical solutions in the embodiments (or "implementations") of the present application will be described clearly and completely in conjunction with the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements.

[0031] If there are terms involving directional indications or positional relationships in the embodiments of the present application (such as up, down, left, right, front, back, inside, outside, top, bottom, center, vertical, horizontal, longitudinal, transverse, length, width, counterclockwise, clockwise, axial, radial, circumferential, etc.), such terms are only used to explain the relative positional relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings); if the specific posture changes, the directional indication or positional relationship will also change accordingly. In addition, the terms "first", "second", etc. involved in the embodiments of the present application are only used for the purpose of convenience of description and cannot be understood as indicating or implying relative importance.

[0032] Next, the embodiments of this specification are described in detail.

[0033] In order to analyze whether the safety mechanism of the braking system meets the technical requirements of functional safety, it is necessary to conduct targeted tests on the key single-point faults in each subcomponent and system that are most likely to violate the safety goals. This test method is the fault injection test method. When simulating fault injection of key components of the braking system, at the vehicle level, the braking system needs to be able to detect faults in time after fault injection and trigger safety mechanisms, switch to safety degradation mode or emergency operation mode, and ensure that the vehicle status is within a controllable range.

[0034] like Figure 1 As shown, the present application provides a braking system functional safety detection device, including a fault injection device 10 and a monitoring device 20. The fault injection device 10 is connected between a vehicle's braking control module 30 and a vehicle network 40 to simulate fault injection of the braking system. The monitoring device 20 is used to monitor the braking system.

[0035] During vehicle driving, the brake control module 30 in the brake system will communicate with the vehicle network 40. The brake control module 30 can receive bus signals from the vehicle network 40 and send bus signals to the vehicle network 40. During the functional safety detection of the brake system, the fault injection device 10 is connected in series between the brake control module 30 and the vehicle network 40, injects faults into a specific bus signal to form a fault signal, and transmits the fault signal between the brake control module 30 and the vehicle network 40. Among them, the specific bus signal refers to the bus signal that needs to be fault injected. The fault signal includes a simulated receiving signal received by the simulated brake control module 30 from the vehicle network 40 and a simulated sending signal sent by the simulated brake control module 30 to the vehicle network 40.

[0036] The fault injection device 10 includes a workstation 11, a first communication adapter box 12 and a fault test box 13 connected in sequence. The first communication adapter box 12 is connected between the workstation 11 and the fault test box 13 through a wiring harness, and the fault test box 13 is connected between the brake control module 30 and the vehicle network 40 through a wiring harness.

[0037] The workstation 11 refers to a computer that can directly issue specific control commands. A program for functional safety detection of the braking system is installed on the workstation 11. By calling the corresponding function in the program, selecting the type of fault injection, and editing the fault injection information of the specific bus signal, the specific bus signal is injected with a fault to form a fault signal. The workstation 11 can also drive the first communication adapter box 12 to transmit the bus signal. The workstation 11 can include electronic devices such as computers and mobile phones.

[0038] The first communication adapter box 12 can simulate the brake control module 30 to send and receive bus signals. During the detection process, the first communication adapter box 12 sends the fault signal to the fault test box 13. In this application, the first communication adapter box 12 is a TC1034 device. The TC1034 device is a high-performance multi-bus analysis and simulation tool used for bus network development, simulation, testing, etc. One end of the first communication adapter box 12 is connected to the workstation 11 through a USB data cable, and the other end is connected to the fault test box 13 through a DB9 female connector with a 4-pin banana plug signal cable.

[0039] Accordingly, the workstation 11 uses TSMaster software to edit the fault injection information of the specific bus signal. TSMaster is a virtual instrument software platform that can adapt to the monitoring and analysis of bus data of automotive Flexray, CAN, and CAN FD networks, vehicle network node simulation, ECU node and system related tests, UDS diagnostic tests, UDS-based ECU flashing, and ECU or vehicle calibration and flashing.

[0040] The fault test box 13 is used to transmit the fault signal to the brake control module 30 and the vehicle network 40. Specifically, the fault test box 13 is provided with a simulated receiving interface 131 and a simulated sending interface 132. The simulated receiving interface 131 is connected to the brake control module 30 and is used to send the simulated receiving signal to the brake control module 30. The simulated sending interface 132 is connected to the vehicle network 40 and is used to send the simulated sending signal to the vehicle network 40.

[0041] Furthermore, the vehicle network 40 includes a Flexray bus and a CAN bus. In the braking system, the sensors strongly related to the brake control module 30 mainly include a steering wheel angle sensor, a wheel speed sensor, an acceleration sensor, a pedal travel sensor, and a master cylinder pressure sensor. Accordingly, the bus signals for communication between the brake control module 30 and the vehicle network 40 include a steering wheel angle signal, a wheel speed signal, an acceleration signal, a pedal travel signal, and a master cylinder pressure signal.

[0042] Among them, the steering wheel angle signal and the acceleration signal are sent from the vehicle network 40 to the brake control module 30 during the braking control process, and are signals that the brake control module 30 needs to receive. The wheel speed signal, the pedal travel signal, and the master cylinder pressure signal are sent from the brake control module 30 to the vehicle network 40 during the braking control process, and are signals sent after being processed by the brake control module 30.

[0043] When the above signal needs to be safety tested, the corresponding signal that needs to be fault injected is used as a specific bus signal, and the fault injection device 10 injects a fault into the specific bus signal to form a fault signal. The fault signal includes a simulated receiving signal and a simulated sending signal, the simulated receiving signal includes at least one of a steering wheel angle signal and an acceleration signal, and the simulated sending signal includes at least one of a wheel speed signal, a pedal travel signal, and a master cylinder hydraulic pressure signal.

[0044] When injecting faults into a specific bus signal, the type of fault injection needs to be selected in the workstation 11 for different fault scenarios. In the present application, the types of fault injection of specific bus signals include signal value injection faults, signal verification faults, and signal loss and jamming faults. Signal value injection faults include setting a specific bus signal to a fixed value, setting a specific bus signal offset, and setting a specific bus signal to scale proportionally. Signal verification faults include signal state validity errors, cyclic redundancy check errors, message count errors, and verification errors. Signal loss and jamming faults include signal loss and signal jamming. The types of fault injection that can be performed on bus signals of different sensors may be different.

[0045] It is understandable that in the functional safety test of the braking system, the fault simulation for the bus signal is mostly single-point fault injection. Therefore, in the detection process, the signal of a single sensor is often selected to perform fault injection in order to more clearly analyze and identify the impact of each sensor failure on the system function. And the number of types of fault injection selected is also single, which helps to simplify the testing process, reduce variables, and make the fault analysis clearer and more accurate. When conducting a comprehensive test and evaluation of the functional safety of the braking system, multiple different bus signals can be tested one by one in a certain order to obtain a more comprehensive and reliable test result.

[0046] Specifically, when performing fault injection, taking the steering wheel angle signal received by the brake control module 30 from the vehicle network 40 as an example, the steering wheel angle message includes signals such as SteeringWheelAngleCS, SteeringWheelAngMsgCnt, SteeringWheelRotDir, SteeringWheelAngleStatus, SteeringWheelAngle, and SteeringWheelAngleSpeed. The fault injection device 10 can be set as follows:

[0047] (1) Setting the steering wheel angle signal to a fixed value The fault injection device 10 sets the steering wheel angle signal to a fixed value a (eg, a=120 degrees).

[0048] (2) Setting the steering wheel angle signal offset: The fault injection device 10 is used to set an offset b (eg, b=60 degrees, b=-60 degrees) based on the current steering wheel angle signal.

[0049] (3) Setting the steering wheel angle signal to be scaled proportionally: The fault injection device 10 sets the steering wheel angle signal to be multiplied by k (eg, k=2, k=0.5) on the original basis.

[0050] (4) Setting the steering wheel angle status validity error: The fault injection device 10 sets the signal value SteeringWheelAngleStatus=0.

[0051] (5) Setting the direction of the steering wheel angle signal to be wrong: The fault injection device 10 sets the signal value SteeringWheelRotDir=1.

[0052] (6) Setting the steering wheel angle signal message count error The fault injection device 10 sets the signal value SteeringWheelAngMsgCnt=0.

[0053] (7) Setting a check sum error for a steering wheel angle signal: The fault injection device 10 sets a check sum error, that is, sets the signal Steering Wheel Angle CS = 0x00.

[0054] (8) Setting the Steering Wheel Angle Speed ​​Signal Stuck The fault injection device 10 sets the steering wheel angle speed signal stuck transmitted by the bus, that is, setting the signal value Steering Wheel Angle Speed ​​= 180 deg / s.

[0055] (9) Setting the steering wheel angle signal missing: The fault injection device 10 sets the steering wheel angle signal transmitted by the bus to be missing.

[0056] When performing fault injection, take the acceleration signal received by the brake control module 30 from the vehicle network 40 as an example, wherein the lateral acceleration message includes signals such as A1, CRC1, MSG_CNT1, and A1_STAT. The fault injection device 10 can be configured as follows:

[0057] (1) Setting the signal value of the lateral acceleration A1 to a certain fixed value. The fault injection device 10 sets the signal of the lateral acceleration A1 to a fixed value c (e.g., c = 5 m / s 2 ).

[0058] (2) Setting the CRC1 cyclic redundancy check error of the lateral acceleration A1 The fault injection device 10 sets CRC1=0 in the current lateral acceleration A1.

[0059] (3) Setting the lateral acceleration A1 to be scaled proportionally: The fault injection device 10 sets the lateral acceleration A1 to be multiplied by k (eg, k=0.5) on the original basis.

[0060] (4) Set the lateral acceleration A1 message count error. Set the signal value MSG_CNT1=0 through the fault injection device 10.

[0061] (5) Setting the lateral acceleration A1 state validity error The fault injection device 10 sets the signal value A1_STAT=0.

[0062] Furthermore, the fault injection device 10 can also be used to inject hard-wire faults and power supply faults into the brake control module 30. Hard-wire faults include short circuits and open circuits of sensor harnesses, communication harnesses, etc. Power supply faults include power supply short circuits, power supply open circuits, power supply voltages that are too high, and power supply voltages that are too low.

[0063] The fault test box 13 is provided with a plurality of switch interfaces 133 , and a plurality of pins in the brake control module 30 are respectively connected to the plurality of switch interfaces 133 , and the plurality of switch interfaces 133 are used to change the connection status of a plurality of pins to simulate hard-wire faults and power supply faults.

[0064] In this embodiment, the fault test box 13 is provided with 46 switch interfaces, which correspond to the 46 pins of the brake control module 30. The pins of the brake control module 30 correspond to the brake fluid level sensor signal, the wheel speed sensor signal, the wheel speed sensor power supply, the CAN bus signal, the Flexray bus signal, the EPB switch signal, the power supply of the EPB electronic caliper, the power supply of the brake control module 30, etc.

[0065] When conducting functional safety testing of the brake system, there is no need to destroy the vehicle's wiring harness circuit. By controlling the on and off of the switch interface 133 on the fault test box 13, the loss or interruption of the wheel speed sensor, CAN bus signal, Flexray bus signal, and power supply failure of the EPB electronic parking caliper and the brake control module 30 can be simulated, thereby simulating hard wire failures and power supply failures.

[0066] Specifically, the switch interface 133 of the present embodiment is of a plug-in type, and an operator can control the on and off of the switch interface 133 by plugging and unplugging a connector at the switch interface 133 .

[0067] When the plug-in components at the switch interface 133 corresponding to the brake fluid level sensor and the wheel speed sensor are pulled out, the signal interruption or loss of the related sensors connected to the brake system can be simulated.

[0068] When the plug-in component at the switch interface 133 corresponding to the CAN bus and the Flexray bus is unplugged, the signal interruption or loss of the braking system network bus loop can be simulated.

[0069] When the plug-in component at the switch interface 133 corresponding to the EPB switch signal and the power supply of the EPB electronic caliper is unplugged, a switch failure or power failure of the EPB electronic parking caliper system can be simulated.

[0070] When the plug-in component at the switch interface 133 corresponding to the power supply of the brake control module 30 is unplugged, a power supply failure of the brake control module 30 can be simulated.

[0071] The braking system functional safety testing device of the present application can be implemented for conventional hard-wire faults and power supply faults by directly controlling the switch interface 133 on the fault test box 13, which is more convenient and quick to operate and more efficient for the functional safety testing of the braking system.

[0072] The monitoring device 20 includes a second communication adapter box 21. The second communication adapter box 21 is connected to the vehicle's on-board communication diagnostic system interface 50 and the workstation 11 through a wiring harness, and is used for real-time monitoring and recording of signal interaction information on the Flexray bus and CAN bus in the vehicle network 40 (such as deceleration during braking, vehicle body yaw angle, etc.), and transmits the recorded information to the workstation 11 for storage to verify whether the fault simulation injected into the specific bus signal is effective.

[0073] In some cases, the monitoring device 20 may also include other devices with data collection functions, such as a data recorder, a visual monitoring device with a camera, a brake pedal feel test device (including a GPS speedometer, an accelerometer, a pedal force meter, a pipeline hydraulic sensor, a data collector, etc.), etc. In the actual test process, the monitoring device 20 can be flexibly selected according to the signals and data information to be collected.

[0074] Specifically, the second communication adapter box 21 is a VN7640 device. The workstation 11 is installed with the Victor CANalyzer software platform to drive the second communication adapter box 21 to record the signal data and changes of the bus transmission in real time. The workstation 11 can monitor the transmission status of the bus signal, input the bus data, and detect the time when the system safety mechanism function is triggered or the fault error is reported after the fault injection through the second communication adapter box 21. The triggered function here refers to the various sub-functions of the braking system such as ABS anti-lock braking, ESC dynamic stability control, AEB automatic emergency braking, HBA emergency braking assist, HDC steep slope descent control, etc., when the tester steps on the brake pedal to stop the vehicle after the fault injection. Whether it can be normally triggered and activated or downgraded and disabled after the fault injection. The fault error reporting time refers to the time interval from the injection of the simulated fault signal to the activation of the system sub-function or the downgrade and disablement of the sub-function, and the triggering of the instrument to light up the brake system fault indicator light.

[0075] like Figure 2 As shown, the present application also provides a braking system functional safety testing method for a vehicle equipped with a braking system functional safety testing device.

[0076] The brake system functional safety detection device includes a fault injection device 10 and a monitoring device 20. The fault injection device 10 is connected in series between the control module 30 and the vehicle network 40, and the monitoring device 20 is connected to the fault injection device 10. The entire brake system functional safety detection device is simple and compact, easy to carry, and quick and convenient to install.

[0077] Specifically, the fault injection device 10 includes a workstation 11, a first communication adapter box 12 and a fault test box 13 connected in sequence. The first communication adapter box 12 is connected between the workstation 11 and the fault test box 13 through a wiring harness, and the fault test box 13 is connected between the brake control module 30 and the vehicle network 40 through a wiring harness. The monitoring device 20 includes a second communication adapter box 21. The second communication adapter box 21 is connected to the vehicle's on-board communication diagnostic system interface 50 and the workstation 11 through a wiring harness.

[0078] In this embodiment, the fault injection device 10 is installed on a real vehicle, and can be tested under real driving conditions, comprehensively considering all dynamic factors under the actual operation of the vehicle, and obtaining more accurate system response and fault performance. In some cases, the fault injection device 10 can also be installed on a test bench to facilitate flexible control of external scene characteristics (such as terrain, slope, road surface conditions, weather changes, etc.) in the functional safety detection of the brake system.

[0079] The braking system functional safety detection method of the present application comprises the following steps:

[0080] S100 , when the vehicle is traveling, a fault injection device 10 is used to inject a fault into a specific bus signal to form a fault signal, and the fault signal is transmitted between the brake control module 30 and the vehicle network 40 .

[0081] The fault signal includes a simulated receiving signal received by the simulated braking control module 30 from the vehicle network 40 and a simulated sending signal sent by the simulated braking control module 30 to the vehicle network 40 .

[0082] In addition, hard-wire faults and power-supply faults may also be injected into the brake control module 30 through the fault injection device 10 to simulate hard-wire faults and power-supply faults of the brake system.

[0083] S200, obtaining the monitoring result of the brake system by the monitoring device 20.

[0084] Obtain the monitoring results of the brake system by the monitoring device 20, including: obtaining the time of function triggering or fault reporting after fault injection; obtaining the display of the brake system fault light of the instrument; obtaining the response of the brake pedal feeling; obtaining the yaw angle of the vehicle body; obtaining the instantaneous deceleration of the vehicle braking. The monitoring device 20 can continuously and real-time monitor the brake system during the entire detection process.

[0085] Please combine Figure 3 In this application, before step S100, the display of the brake system fault light of the instrument is determined. If the brake system fault light indicates that the brake system is faulty, the detection is suspended and the fault is analyzed. If the brake system fault light indicates that the brake system is not faulty, step S100 is executed.

[0086] After executing step S100, the display of the brake system fault light of the instrument is determined again. If the brake system fault light indicates that the brake system is faulty, the fault injection is successful and the test data is recorded. If the brake system fault light is not lit, it means that the fault injection has failed or the brake system fault light is faulty, and the test is suspended for analysis.

[0087] After the fault injection is successful, monitor the time from fault injection to the lighting of the brake system fault light to evaluate the response speed of the brake system to the fault. Press the brake pedal to brake until the vehicle stops, monitor the brake pedal travel and foot feel feedback, the maximum deceleration and time generated by the vehicle, and the yaw angle from fault injection to vehicle body stop, and evaluate the vehicle's braking performance and braking stability under fault conditions.

[0088] After the vehicle body stops steadily, stop injecting faults into the bus signal, then control the vehicle to power off, shut down the engine and put it into sleep mode. Restart the vehicle and confirm the display of the brake system fault light on the instrument again.

[0089] Taking the fault injection detection of the steering wheel angle signal as an example, the detection steps of an embodiment are as follows:

[0090] (1) Control the vehicle to power on and the engine to idle.

[0091] (2) Check the instrument to see if the brake system fault light is on.

[0092] (3) If the brake system fault light is not on, control the vehicle to drive straight on the high-adhesion road surface in the test area at a speed of 30 km / h.

[0093] (4) The tester implements simulated fault injection on the steering wheel angle signal through the fault injection device 10 during driving.

[0094] (5) Check the instrument to see if the brake system fault light is on.

[0095] (6) If the brake system fault light is on, the monitoring device 20 reads the time from the injection of the fault to the lighting of the instrument fault light, and monitors whether the brake system fault light is always on.

[0096] (7) After the brake system fault light is detected, the driver steps on the brake pedal to brake the vehicle until it stops. The maximum deceleration and time generated by the vehicle, and the yaw angle of the vehicle from the start of fault injection to the vehicle stopping are monitored.

[0097] (8) The tester stops the fault injection through the fault injection device 10 and controls the vehicle to power off and shut down the engine to sleep.

[0098] (9) After restarting the engine, observe the display status of the brake system fault light.

[0099] (10) Based on the data read by the monitoring device 20, the braking performance and functional degradation of the braking system are evaluated.

[0100] It is understandable that, during the functional safety testing of the brake system, the data monitored, read and saved by the monitoring device 20 can be flexibly selected and set to meet different testing needs and improve the efficiency and effect of the testing.

[0101] The braking system functional safety detection device and method of the present application injects faults into a specific bus signal through a fault injection device 10 to form a fault signal, and transmits the fault signal between the braking control module 30 and the vehicle network 40, thereby simulating the communication fault between the braking control module 30 and the vehicle network 40.

[0102] The fault signal includes a simulated receiving signal received by the simulated braking control module from the vehicle network and a simulated sending signal sent by the simulated braking control module to the vehicle network. It can comprehensively evaluate the response capability of the braking control module 30 to the data sent by the vehicle network 40 and the effectiveness of the braking control module 30 sending information to the vehicle network 40, and more accurately simulate, detect and analyze various fault situations, thereby improving the reliability and accuracy of detection.

[0103] At the same time, the fault injection device 10 can also be used to simulate hard-wire faults and power supply faults of the braking system to improve the comprehensiveness of the braking system functional safety detection device and method, more accurately identify and evaluate various potential safety hazards of the braking system, optimize the safety design, and improve the safety and reliability of the braking system.

[0104] It should be noted that the technical solutions or technical features described in the above embodiments can be combined or supplemented with each other without causing conflicts. The scope of protection of this application is not limited to the precise structures described in the above embodiments and shown in the drawings; all modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of this application should be included in the scope of protection of this application.

Claims

1. A braking system functional safety detection device, characterized in that: Including fault injection equipment and monitoring equipment, The fault injection device is connected between the brake control module of the vehicle and the whole vehicle network, and is used to inject faults into a specific bus signal to form a fault signal, and transmit the fault signal between the brake control module and the whole vehicle network; the fault signal includes a simulated receiving signal received by the brake control module from the whole vehicle network and a simulated sending signal sent by the brake control module to the whole vehicle network; The monitoring device is used to monitor the braking system.

2. The braking system functional safety detection device according to claim 1, characterized in that: The fault injection device comprises a workstation, a first communication switching box and a fault test box which are connected in sequence, and the fault test box is connected between the brake control module and the vehicle network.

3. The braking system functional safety detection device according to claim 2, characterized in that: The fault test box is provided with an analog receiving interface connected to the brake control module and an analog sending interface connected to the whole vehicle network. The analog receiving interface sends the analog receiving signal to the brake control module, and the analog sending interface sends the analog sending signal to the whole vehicle network.

4. The braking system functional safety detection device according to claim 2, characterized in that: The monitoring device comprises a second communication adapter box, and the second communication adapter box is respectively connected to the vehicle-mounted communication diagnostic system interface of the vehicle and the workstation.

5. The braking system functional safety detection device according to claim 4, characterized in that: The first communication adapter box is TC1034, the second communication adapter box is VN7640, and the workstation uses TSMaster software to edit the fault injection information of the specific bus signal.

6. The braking system functional safety detection device according to claim 2, characterized in that: The fault injection device is also used to inject hard-wire faults and power supply faults into the brake control module. The hard-wire faults include short circuits and open circuits of the communication harness; the power supply faults include power supply short circuits, power supply open circuits, excessive power supply voltage, and excessive power supply voltage.

7. The braking system functional safety detection device according to claim 6, characterized in that: The fault test box is provided with a plurality of switch interfaces, and a plurality of pins in the brake control module are respectively connected to the plurality of switch interfaces, and the plurality of switch interfaces are used to change the connection states of the plurality of pins to simulate the hard line fault and the power supply fault.

8. The braking system functional safety detection device according to claim 1, characterized in that: The analog receiving signal includes at least one of a steering wheel angle signal and an acceleration signal; the analog sending signal includes at least one of a wheel speed signal, a pedal travel signal, and a master cylinder pressure signal.

9. The braking system functional safety detection device according to claim 1, characterized in that: The types of fault injection of the specific bus signal include signal value injection faults, signal verification faults, and signal loss and stuck faults.

10. The braking system functional safety detection device according to claim 9, characterized in that: The signal value injection fault includes setting the specific bus signal to a fixed value, setting the specific bus signal offset, and setting the specific bus signal to be scaled proportionally; the signal verification fault includes signal state validity error, cyclic redundancy check error, message count error, and verification error; the signal loss and jamming fault includes signal loss and signal jamming.

11. A brake system functional safety testing method, used for a vehicle equipped with a brake system functional safety testing device, characterized in that: The braking system functional safety detection device includes a fault injection device and a monitoring device, and the method includes the following steps: When the vehicle is running, a fault injection device is used to inject a fault into a specific bus signal to form a fault signal, and the fault signal is transmitted between the brake control module and the vehicle network; the fault signal includes a simulated receiving signal received by the simulated brake control module from the vehicle network and a simulated sending signal sent by the simulated brake control module to the vehicle network; Obtain the monitoring results of the braking system by the monitoring equipment.

12. The brake system functional safety detection method according to claim 11, characterized in that: The monitoring result of the braking system by the monitoring device is obtained, including: obtaining the time of function triggering or fault reporting after fault injection; obtaining the display of the brake system fault light of the instrument; obtaining the response of the brake pedal feeling; obtaining the vehicle body yaw angle; and obtaining the vehicle braking instantaneous deceleration.

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