Simulink-based vehicle crash switch detection logic, models, and devices incorporating the same

Abstract

The application discloses a Simulink-based automobile collision switch detection logic and model, detects automobile collision output signals, and enables an automobile control unit to quickly and correctly detect whether a collision occurs or a signal is faulty. The algorithm logic is set as follows: in a normal case, a collision output signal keeps 80ms high level to 20ms low level cyclic variation, which is a pulse width modulation signal with a duty cycle of 80%; when a collision occurs, an airbag is ignited; from the ignition time, the collision output signal continuously sends at least 10 pulse width modulation signals with a duty cycle of 20%; if the signal accuracy is a%, when the automobile control unit continuously detects 2-3 pulse width modulation signals with a duty cycle of (20-a)% to (20+a)% in the collision output signal, it is considered that a collision occurs; and when 2-3 signals with a duty cycle out of the range of (80-a)% to (80+a)% or (20-a)% to (20+a%) are continuously detected, it is considered that the collision output signal is faulty.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of automobile collision switch detection, and more particularly to an automobile collision switch detection logic based on Simulink, a model and a device containing the same. BACKGROUND

[0002] Single-chip microcomputers are increasingly important for modern automobiles, are widely used in various aspects of automobiles, and are integrated with various components to play a greater efficiency. Of course, this also causes some hidden dangers, such as the increase of vehicle speed and the influence from external environment, which can easily cause traffic accidents, especially with the development of new energy vehicles, the battery as an energy storage component, once a collision occurs and cannot provide effective detection and protection, it is easy to cause serious accidents. The design of collision detection logic is an important part of collision detection. It is particularly important to quickly and stably realize the logic design of signal detection, realize the judgment of the collision signal and feedback to the vehicle system, so that the vehicle can make corresponding judgments and reduce the damage of traffic accidents.

[0003] Chinese patent application with publication number CN 101151176A discloses a method for detecting the reliability of sensor signals of an automobile system, wherein the sensor signals are detected by means of a corresponding algorithm in compliance with one or more reliability detection criteria, characterized in that the driving state of the automobile is monitored with respect to a collision, and at least one reliability detection criterion is changed when a collision is found. The method solves the problem that the traditional reliability detection method works well enough in normal driving operation, but in the limit case of driving dynamics, for example, after a collision, signal values or signal changes that greatly exceed the reliable range can occur, and the sensor signals involved are then classified as unreliable or distorted by too strong filtering. The technical solution changes at least one reliability detection criterion, such as modifying the pre-set boundary value for absolute value or allowed signal change, when a collision is found, so that the function of the upper system is maintained even in the limit case, but it is not clear how to set this criterion according to different dynamic scenarios, that is, the automobile control unit is not clear about what standard to use for collision judgment when encountering different scenarios. SUMMARY

[0004] Since the prior art has the above-mentioned defects, the present application provides an automobile collision switch detection logic based on Simulink, a model and a device containing the same, which designs an algorithm logic to detect the automobile collision output signal (CRO), so that the automobile control unit (VCU) can quickly and accurately detect whether a collision occurs, and ensure the safety of vehicles and persons.

[0005] To achieve the above object, in one aspect, the application provides a Simulink-based automobile collision switch detection logic, characterized by using the Simulink system in MATLAB to design the following algorithm logic to detect the automobile collision output signal, so that the automobile control unit can correctly detect whether a collision occurs:

[0006] Under normal circumstances, the collision output signal keeps changing from 80 ms high level to 20 ms low level in a cycle, which is a pulse width modulation signal with a duty cycle of 80%;

[0007] When a collision occurs, the airbag ignites; from the ignition time, the collision output signal continuously sends at least 10 pulse width modulation signals with a duty cycle of 20%;

[0008] If the signal accuracy is a%, when the automobile control unit continuously detects 2-3 pulse width modulation signals with a duty cycle of (20-a)%-(20+a)%, it is considered that a collision has occurred; when 2-3 signals with a duty cycle outside the range of (80-a)%-(80+a)% or (20-a)%-(20+a)% are continuously detected, it is considered that the collision output signal has failed.

[0009] Further, the signal accuracy is 5%-10%, which can be modified according to the accuracy requirement.

[0010] Further, after the automobile is powered on for a set time, when the first rising edge or the first falling edge is detected, the collision signal detection is started. Preferably, after the automobile is powered on for 5 seconds, when the first rising edge or the first falling edge is detected, the collision signal detection is started.

[0011] Further, after the signal detection is started, every time an rising edge or a falling edge is passed, the last high level signal or low level signal is sent out in a counting manner, and whether the signal is a collision signal is judged according to the length of the signal.

[0012] Further, when a collision signal occurs, the collision signal flag is set to 1; when a signal failure occurs, the signal failure flag is set to 1; the two signals cannot occur at the same time.

[0013] Further, the automobile collision power-off effective condition includes that the collision signal flag is set to 1 and the collision signal output is effective.

[0014] On the other hand, the application provides a Simulink-based automobile collision switch detection model, characterized by being developed based on the above automobile collision switch detection logic and using the Simulink system in MATLAB.

[0015] In still another aspect, the present application provides a device for detecting an automobile crash switch, which can receive and monitor a crash output signal, characterized in that it comprises an electronic device with the automobile crash switch detection algorithm logic as described above.

[0016] Further, when the device is used in an electric automobile, the high voltage output of the motor power and the power battery is timely cut off when the crash signal output by the crash switch is detected.

[0017] Compared with the prior art, the above-mentioned application has the following advantages or beneficial effects:

[0018] (1) The present application realizes rapid and stable crash switch detection and signal fault detection of the crash output signal by giving the initial pulse width modulation signal and the abnormal pulse width modulation signal with obvious duty cycle difference, and the clear monitoring and judging strategy.

[0019] (2) The present application develops an automobile crash switch detection model through Simulink system, and has good algorithm adaptability, convenient and stable algorithm implementation, and strong industrial practicability.

[0020] The present application discloses an automobile crash switch detection logic and model based on Simulink, which detects the automobile crash output signal, so that the automobile control unit can rapidly and correctly detect whether a crash occurs or a signal is faulty. The algorithm logic is set as follows: under normal circumstances, the crash output signal keeps cyclically changing from 80 ms high level to 20 ms low level, which is a pulse width modulation signal with a duty cycle of 80%; when a crash occurs, the airbag is ignited; from the ignition time, the crash output signal continuously sends at least 10 pulse width modulation signals with a duty cycle of 20%; if the signal accuracy is a%, when the automobile control unit continuously detects that the crash output signal appears 2-3 pulse width modulation signals with a duty cycle of (20-a)%-(20+a)%, it is considered that a crash occurs; when 2-3 signals with a duty cycle out of the range of (80-a)%-(80+a)% or (20-a)%-(20+a)% are continuously detected, it is considered that the crash output signal is faulty. BRIEF DESCRIPTION OF DRAWINGS

[0021] The present application, its features and advantages will become more apparent upon reading the following detailed description of non-restrictive embodiments with reference to the accompanying drawings. The same references denote the same parts throughout the drawings. The drawings are not necessarily drawn to scale, the emphasis being on illustrating the principle of the present application.

[0022] Figure 1 FIG. 1 is a schematic diagram of an automobile crash switch detection logic in an embodiment of the present application;

[0023] Figure 2Pulse width modulation signal output by CRO in normal situation and when collision occurs in an embodiment of the present application;

[0024] Figure 3 Simulink-based automobile collision switch detection model in an embodiment of the present application;

[0025] Figure 4 For Figure 3 A portion of the enlarged schematic diagram in the present application;

[0026] Figure 5 For Figure 3 B portion of the enlarged schematic diagram in the present application;

[0027] Figure 6 Signal detection result simulated by the automobile collision switch detection model in an embodiment of the present application;

[0028] Figure 7 Detection test result schematic diagram of SRS collision signal generated after power-on of the automobile collision switch detection model in an embodiment of the present application, in which the safety airbag controller and the VCU controller are connected for test;

[0029] Figure 8 Detection test result schematic diagram of SRS collision signal circuit break after power-on of the automobile collision switch detection model in an embodiment of the present application, in which the safety airbag controller and the VCU controller are connected for test;

[0030] Figure 9 Detection test result schematic diagram of SRS collision signal grounding after power-on of the automobile collision switch detection model in an embodiment of the present application, in which the safety airbag controller and the VCU controller are connected for test;

[0031] Figure 10 Detection test result schematic diagram of SRS collision signal power connection after power-on of the automobile collision switch detection model in an embodiment of the present application, in which the safety airbag controller and the VCU controller are connected for test;

[0032] Figure 11 Detection test result schematic diagram of SRS collision signal circuit break before power-on of the automobile collision switch detection model in an embodiment of the present application, in which the safety airbag controller and the VCU controller are connected for test;

[0033] Figure 12 Detection test result schematic diagram of SRS collision signal grounding before power-on of the automobile collision switch detection model in an embodiment of the present application, in which the safety airbag controller and the VCU controller are connected for test;

[0034] Figure 13The detection test result schematic diagram of the SRS collision signal power supply connection test before power-on for the safety air bag controller and the VCU controller connected to the automobile collision switch detection model in an embodiment of the present application. DETAILED DESCRIPTION

[0035] The structure in the present application will be further described below in combination with the drawings and specific embodiments, but not as a limitation of the present application.

[0036] EMBODIMENT

[0037] Referring to Figure 1 The present embodiment provides a Simulink-based automobile collision switch detection logic, which uses the Simulink system in MATLAB to design the following algorithm logic, detects the automobile collision output signal, and enables the automobile control unit to correctly detect whether a collision occurs:

[0038] Referring to Figure 2 Under normal circumstances, the collision output signal keeps changing from 80 ms high level to 20 ms low level in a cycle, which is a pulse width modulation signal with a duty cycle of 80%; when a collision occurs, the safety air bag ignites; from the ignition time, the collision output signal continuously sends at least 10 PWM signals with a duty cycle of 20%.

[0039] If the signal accuracy is a%, when the automobile control unit continuously detects 2-3 pulse width modulation signals with a duty cycle of (20-a)%-(20+a)%, it is considered that a collision has occurred; when 2-3 signals with a duty cycle outside the range of (80-a)%-(80+a)% or (20-a)%-(20+a)% are continuously detected, it is considered that the collision output signal has failed. Preferably, the signal accuracy is generally 5%-10%, which can be modified by calibration, i.e. the value range of a can be matched and modified according to the designed signal accuracy parameters.

[0040] Figure 3 The safety air bag collision signal model designed by using the Simulink system in MATLAB in combination with the automobile collision switch detection logic, which judges whether the safety air bag has signal failure or collision working condition by detecting the CRO signal. Referring to Figure 4 After power-on for several seconds, when the first rising edge or the first falling edge is detected, the collision signal detection is started. As an example, in the present embodiment, after power-on for 5 seconds, when the first rising edge or the first falling edge is detected, the collision signal detection is started.

[0041] Referring to Figure 5After the start signal detection, every time after a rising edge or a falling edge, the previous high level signal or low level signal is sent out in a counting way, and whether the signal is a collision signal is judged according to the length of the signal. When the collision signal appears, the collision signal flag is 1. When the signal fault appears (such as the signal is always high, always low, or the length is incorrect), the signal fault flag is 1. And the two signals cannot occur at the same time.

[0042] The parameters calibrated by the model include:

[0043] 1. KDSM_IgnOnCrashDly_cnt, meaning: start collision signal detection after power-on for more than 5 seconds, initial value is set to 500 (can be calibrated and modified).

[0044] 2. KDSM_CrashSigChk_cnt, meaning: if 20 consecutive steps of collision signals are detected to be always high or always low, the signal fault is set, and the initial value is set to 20 (can be calibrated and modified).

[0045] 3. KDSM_CrashSigFltChk_cnt, meaning: if 4 consecutive periods of collision signals are detected to be abnormal, the signal fault is set, and the initial value is set to 8 (can be calibrated and modified).

[0046] 4. KDSM_CrashDetdFltChk_cnt, meaning: if 3 consecutive periods of collision conditions are detected, the collision signal is set, and the initial value is set to 6 (can be calibrated and modified).

[0047] The failure analysis that can be performed by the model includes:

[0048] 1. When the input collision signal fails, the signal fault flag is set.

[0049] 2. When the output collision condition flag and the signal fault flag fail, the VCU cannot send out the collision signal fault.

[0050] As a preferred technical solution, the effective condition of the automobile collision power-off includes that the collision signal flag is 1 and the collision signal output is effective.

[0051] The test data and records of the model are as follows:

[0052] As Figure 6As shown, the first row waveform is an analog CRO signal, the second row waveform is a collision signal, and the third row waveform is a signal fault. In the normal signal stage (high level 80 ms, low level 20 ms), no fault response occurs. Both the collision signal and the signal fault response are set to 0. When a continuous high level of 80 ms occurs, the signal fault flag is set to 1, and when a low level of 80 ms, a high level of 20 ms, and a continuous three cycles occur, the signal collision flag is set to 1. By Figure 6 It can be seen that the model can meet the detection requirements.

[0053] The airbag controller and the VCU controller are connected to test the collision signal, and the test results are shown in Figures 7 to 13 According to the MATLAB simulation results and the actual test results, the algorithm can effectively determine the change of the collision signal, detect whether a collision occurs, and whether the collision signal is invalid.

[0054] It can be understood that the above-mentioned automobile collision switch detection algorithm logic can be written into an electronic device for detecting an automobile collision switch, and when the collision switch output collision signal is detected, the motor power output and the power battery high-voltage output are timely cut off when the device is used in an electric vehicle.

[0055] In the specification provided herein, a large number of specific details are described. However, it can be understood that embodiments of the present application can be practiced without these specific details. In some examples, well-known methods, structures, and techniques are not shown in detail in order not to obscure the understanding of the present specification.

[0056] In summary, the present application discloses a Simulink-based automobile collision switch detection logic and model, which detects the automobile collision output signal, so that the automobile control unit can quickly and correctly detect whether a collision occurs or the signal is faulty. The algorithm logic is set as follows: in a normal situation, the collision output signal remains in a 80 ms high level to 20 ms low level cycle change, which is a pulse width modulation signal with a duty cycle of 80%; when a collision occurs, the airbag ignites; from the time of ignition, the collision output signal continuously sends at least 10 pulse width modulation signals with a duty cycle of 20%; if the signal accuracy is a%, when the automobile control unit continuously detects 2-3 pulse width modulation signals with a duty cycle of (20-a)% to (20+a)%, it is considered that a collision has occurred; when 2-3 signals with a duty cycle of (80-a)% to (80+a)% or (20-a)% to (20+a)% are continuously detected, it is considered that the collision output signal has failed.

[0057] Those skilled in the art will appreciate that modules in the apparatuses of the embodiments can be adapted and placed in one or more apparatuses other than the embodiments. Modules or units or components in the embodiments can be combined into one module or unit or component, and furthermore can be divided into multiple sub-modules or sub-units or sub-components.

[0058] The present application can also be embodied in an apparatus or device program (e.g., a computer program and a computer program product) for performing part or all of the algorithms described herein. Such a device program can be stored on a computer-readable medium or can be in the form of one or more signals. Such a signal can be downloaded from an Internet website, or provided on a carrier signal, or in any other form.

[0059] The preferred embodiments of the present application have been described above. It is understood that the present application is not limited to the particular embodiments described above, in which the devices and structures have not been described in detail, and should be understood as being implemented in the ordinary way in the art; any person skilled in the art, without departing from the scope of the technical solutions of the present application, can make many possible changes and modifications to the technical solutions disclosed above, or modify them into equivalent embodiments, which do not affect the essential content of the present application. Therefore, any simple modification, equivalent change and modification made to the above embodiments in accordance with the technical essence of the present application, without departing from the scope of the technical solutions of the present application, shall still fall within the scope of protection of the technical solutions of the present application.

Claims

1. A Simulink-based automotive crash switch detection method Method characterized in that The following algorithm logic is designed by using Simulink system in MATLAB, so that the automobile control unit can correctly detect whether the collision occurs or not: Under normal circumstances, the collision output signal keeps 80ms high level to 20ms low level cycle change, which is a pulse width modulation signal with duty cycle of 80%; When collision occurs, the airbag ignites; from the ignition time, the collision output signal continuously sends at least 10 PWM signals with duty cycle of 20%; If the signal accuracy is a%, when the automobile control unit continuously detects 2-3 pulse width modulation signals with duty cycle of (20-a)%-(20+a)%, it is considered that the collision occurs; when 2-3 signals with duty cycle of (80-a)%-(80+a)% or (20-a)%-(20+a)% are continuously detected, it is considered that the collision output signal fails; after the automobile is powered on for a set time, when the first rising edge or the first falling edge is detected, the collision signal detection is started; after the automobile is powered on for 5 seconds, when the first rising edge or the first falling edge is detected, the collision signal detection is started; after the signal detection is started, every time a rising edge or a falling edge is passed, the last high level signal or low level signal is sent out in a counting manner, and whether the signal is a collision signal is judged according to the length of the signal.

2. The Simulink-based vehicle crash switch detection method of claim 1, wherein, The signal accuracy is 5%-10%, which can be modified according to the accuracy requirement.

3. The Simulink-based vehicle crash switch detection method of claim 1, wherein, When the collision signal occurs, the collision signal flag is 1; when the signal fails, the signal failure flag is 1; the two signals cannot occur at the same time.

4. The Simulink-based vehicle crash switch detection method of claim 3, wherein, The effective conditions of automobile collision power-off include that the collision signal flag is 1 and the collision signal output is effective.

5. A device for detecting an automotive crash switch, capable of receiving and monitoring a crash output signal, characterized by, The electronic device comprising the automobile collision switch detection method according to any one of claims 1-4.

6. A device for detecting a vehicle crash switch according to claim 5, wherein When the device is used in an electric vehicle, when the collision signal output by the collision switch is detected, the motor power output and the high-voltage output of the power battery are cut off in time.

Images