Vehicle collision detection method

Abstract

The invention discloses a vehicle collision detection method, which relates to the field of vehicle collision detection. It solves the problem that when the vehicle frequently accelerates and decelerates, the existing method may cause misjudgment due to frequent changes in acceleration, and the method cannot give the problem of which direction the vehicle collides. The following scheme is proposed, which includes the following steps: when the acceleration in the x direction suddenly increases to ax1, if the accelerator pedal is stepped on, the vehicle acceleration ax2 is calculated according to the accelerator position, if ax1 is much greater than ax2, it is judged that a rearward collision occurs, if ax1 is much less than ax2, it is judged that a forward collision occurs; when the acceleration in the x direction suddenly drops to ax1, if the brake pedal is stepped on, the vehicle acceleration ax3 is calculated according to the brake position, if ax1 is much greater than ax3, it is judged that a rearward collision occurs, if ax1 is much less than ax3, it is judged that a forward collision occurs. The device has the characteristics that the collision detection method based on the acceleration sensor and the pedal position can ensure high detection accuracy and reduce the probability of misjudgment.

Description

Technical Field

[0001] The present invention relates to the field of vehicle collision detection, and in particular to a vehicle collision detection method. Background Art

[0002] As the level of vehicle intelligence increases, the demand for active and passive safety technologies becomes stronger. There is always a possibility of collision when a vehicle is driving or parking on the road. Vehicle collision detection can provide warnings to vehicle drivers and passengers, and also provide external sensor input for vehicle autonomous control.

[0003] The Chinese invention patent number is 201510497542.9, the application date is August 13, 2015, and the name is a vehicle collision detection method and rapid processing system. It discloses the following steps: setting the collision parameters of the first preset time T1, the second preset time T2, the preset acceleration value K, and the preset speed value V; collecting the real-time acceleration value M and the real-time speed value N of the vehicle; determining whether the real-time acceleration value M of the vehicle exceeds the preset acceleration value K within the first preset time T1; determining whether the real-time speed value N of the vehicle drops below the preset speed value V within the second preset time T2; and finally sending the vehicle's location information, the maximum acceleration value M and the maximum speed value N collected at time T1 to a third-party monitoring center, and the third-party monitoring center arranges rescue according to the acquired information. By adopting the method and system of the present invention, the accuracy of collision detection can be effectively improved and the false alarm rate can be reduced. That is, whether a collision occurs is determined by the feature that the acceleration increases first and then decreases. When the vehicle frequently accelerates and decelerates, the method may make a misjudgment due to the frequent changes in acceleration, and the method cannot give the direction in which the vehicle collides. Similarly, Chinese invention patents with patent numbers 201710027218.X, 201610581404.3, and 201811256531.1 also disclose similar technologies, which also have the possibility of misjudgment of collision. Therefore, a vehicle collision detection method is proposed. Summary of the invention

[0004] The purpose of the present invention is to provide a vehicle collision detection method, which solves the problem that when the vehicle frequently accelerates and decelerates, the existing method may make a misjudgment due to the frequent changes in acceleration, and the method cannot tell in which direction the vehicle collides.

[0005] To achieve the above object, the present invention provides the following technical solution: a vehicle collision detection method, using a three-axis acceleration sensor to detect whether a collision occurs in the x direction of a typical vehicle coordinate system during vehicle driving, comprising the following steps:

[0006] (1) measuring the acceleration ax in the x direction with a period T;

[0007] (2) When the acceleration in the x direction suddenly increases to ax1, the following judgments are performed according to whether the accelerator pedal is pressed:

[0008] If the accelerator pedal is pressed, the vehicle acceleration ax2 is calculated based on the accelerator position. If ax1 is much greater than ax2, a rearward collision is determined to have occurred. If ax1 is much less than ax2, a forward collision is determined to have occurred.

[0009] If the accelerator pedal is not depressed, it is determined that a rearward collision has occurred;

[0010] (3) When the acceleration in the x direction suddenly drops to ax1, the following judgments are performed depending on whether the brake pedal is pressed:

[0011] If the brake pedal is pressed, the vehicle acceleration ax3 is calculated based on the brake position. If ax1 is much greater than ax3, a rear collision is determined to have occurred. If ax1 is much less than ax3, a forward collision is determined to have occurred.

[0012] If the brake pedal is not depressed, it is determined that a forward collision has occurred.

[0013] Preferably, the vehicle acceleration when the accelerator pedal is depressed is determined using a pre-calibration.

[0014] Preferably, the vehicle acceleration when the brake pedal is depressed is determined using a pre-calibrated value.

[0015] A vehicle collision detection method uses a three-axis acceleration sensor to detect whether a collision occurs in the y direction of a typical vehicle coordinate system during vehicle driving, comprising the following steps:

[0016] (1) Measure the acceleration ay in the y direction with a period T;

[0017] (2) When the acceleration in the y direction suddenly increases to ay1, it is judged that a collision has occurred on the left side;

[0018] (3) When the acceleration in the y direction suddenly drops to ay1, it is judged that a collision has occurred on the right side.

[0019] A vehicle collision detection method uses a three-axis acceleration sensor to detect whether a collision occurs in the z direction of a typical vehicle coordinate system during vehicle driving, comprising the following steps:

[0020] (1) measuring the acceleration az in the z direction with a period T;

[0021] (2) When the acceleration in the z direction suddenly increases to az1, it is judged that a collision has occurred below;

[0022] (3) When the acceleration in the z direction suddenly drops to az1, it is judged that a collision has occurred above.

[0023] Preferably, if the acceleration in the x, y or z direction at a certain moment obviously exceeds the historical average value, it is considered that the acceleration in this direction has suddenly increased or decreased.

[0024] Compared with the related art, the vehicle collision detection method provided by the present invention has the following beneficial effects:

[0025] The present invention provides a vehicle collision detection method. Compared with the prior art, the collision detection method based on an acceleration sensor and combined with a pedal position proposed by the present invention can ensure higher detection accuracy and reduce the probability of misjudgment. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The present invention is a flow chart of x-direction collision detection in a vehicle collision detection method.

[0027] Figure 2 The present invention is a flow chart of collision detection in the y direction in a vehicle collision detection method.

[0028] Figure 3 The present invention is a flow chart of z-direction collision detection in a vehicle collision detection method. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0030] Embodiment 1:

[0031] See also Figure 1-3 The present invention provides a technical solution: a vehicle collision detection method, using a three-axis acceleration sensor to detect whether a collision occurs in the x direction of a typical vehicle coordinate system during vehicle driving, comprising the following steps:

[0032] (1) measuring the acceleration ax in the x direction with a period T;

[0033] (2) When the acceleration in the x direction suddenly increases to ax1, the following judgments are performed according to whether the accelerator pedal is pressed:

[0034] If the accelerator pedal is pressed, the vehicle acceleration ax2 is calculated based on the accelerator position. If ax1 is much greater than ax2, a rearward collision is determined to have occurred. If ax1 is much less than ax2, a forward collision is determined to have occurred.

[0035] If the accelerator pedal is not depressed, it is determined that a rearward collision has occurred;

[0036] (3) When the acceleration in the x direction suddenly drops to ax1, the following judgments are performed depending on whether the brake pedal is pressed:

[0037] If the brake pedal is pressed, the vehicle acceleration ax3 is calculated based on the brake position. If ax1 is much greater than ax3, a rear collision is determined to have occurred. If ax1 is much less than ax3, a forward collision is determined to have occurred.

[0038] If the brake pedal is not depressed, it is determined that a forward collision has occurred.

[0039] The vehicle acceleration when the accelerator pedal is depressed is determined using a pre-calibration, and the vehicle acceleration when the brake pedal is depressed is determined using a pre-calibration.

[0040] A vehicle collision detection method uses a three-axis acceleration sensor to detect whether a collision occurs in the y direction of a typical vehicle coordinate system during vehicle driving, comprising the following steps:

[0041] (1) Measure the acceleration ay in the y direction with a period T;

[0042] (2) When the acceleration in the y direction suddenly increases to ay1, it is judged that a collision has occurred on the left side;

[0043] (3) When the acceleration in the y direction suddenly drops to ay1, it is judged that a collision has occurred on the right side.

[0044] A vehicle collision detection method uses a three-axis acceleration sensor to detect whether a collision occurs in the z direction of a typical vehicle coordinate system during vehicle driving, comprising the following steps:

[0045] (1) measuring the acceleration az in the z direction with a period T;

[0046] (2) When the acceleration in the z direction suddenly increases to az1, it is judged that a collision has occurred below;

[0047] (3) When the acceleration in the z direction suddenly drops to az1, it is judged that a collision has occurred above.

[0048] If the acceleration in the x, y or z direction at a certain moment obviously exceeds the historical average value, it is considered that the acceleration in that direction has increased or decreased suddenly.

[0049] In this embodiment, in the vehicle's classical coordinate system, the positive x direction is forward, the positive y direction is rightward, and the positive z direction is upward. A three-axis acceleration sensor can be used to measure the acceleration values ​​of the vehicle in three directions. When the acceleration sensor is not arranged in the standard x, y, and z directions, the acceleration in each direction can be set to zero to complete initialization by calibration.

[0050] The controller connected to the acceleration sensor periodically detects the acceleration values ​​in three directions, preferably with a detection period of 5ms, and calculates the average values ​​of the acceleration values ​​in the three directions. When the acceleration value at a certain detection moment significantly exceeds the change in the average value, it is considered that an acceleration surge or drop has occurred in that direction, thereby triggering the subsequent collision detection algorithm. Here, it is set that a mutation occurs when the value exceeds the average value by 10%.

[0051] The change in x-direction acceleration is caused by collision and active acceleration and deceleration of the vehicle. In order to accurately identify a collision, the influence of active acceleration and deceleration of the vehicle needs to be eliminated. The acceleration value of the vehicle under different accelerator and brake pedal positions is determined by offline testing, and then compared with the x-direction acceleration value ax1 obtained by real-time measurement. The details are as follows:

[0052] If the accelerator pedal is pressed, the vehicle acceleration ax2 is calculated based on the accelerator position. If ax1 is much greater than ax2, a rear collision is determined to have occurred. If ax1 is much less than ax2, a forward collision is determined to have occurred.

[0053] If the accelerator pedal is not depressed, it is determined that a rearward collision has occurred;

[0054] If the brake pedal is pressed, the vehicle acceleration ax3 is calculated based on the brake position. If ax1 is much greater than ax3, a rear collision is determined to have occurred. If ax1 is much less than ax3, a front collision is determined to have occurred.

[0055] If the brake pedal is not depressed, it is determined that a forward collision has occurred.

[0056] Considering that the vehicle does not turn much, the sudden change in acceleration in the y direction is mainly caused by collisions in the left and right directions. Compared with the x direction, the collision judgment in the y direction follows the following method:

[0057] When the acceleration in the y direction suddenly increases to ay1, it is judged that a collision occurs on the left side;

[0058] When the acceleration in the y direction suddenly drops to ay1, it is determined that a collision has occurred on the right side.

[0059] Considering that the road is flat, the sudden change in acceleration in the y direction is mainly caused by the collision in the up and down directions. The collision in the z direction follows the following method:

[0060] When the acceleration in the z direction suddenly increases to az1, it is judged that a collision occurs below;

[0061] When the acceleration in the z direction suddenly drops to az1, it is determined that a collision has occurred above.

Claims

1. A vehicle collision detection method, using a three-axis acceleration sensor to detect whether a collision occurs in the x-direction of a typical vehicle coordinate system during vehicle driving, characterized in that: The following steps are involved: (1) Measure the acceleration ax in the x direction with a period T; (2) When the acceleration in the x direction suddenly increases to ax1, the following judgments are performed depending on whether the accelerator pedal is pressed: If the accelerator pedal is pressed, the vehicle acceleration ax2 is calculated based on the accelerator position. If ax1 is much greater than ax2, a rearward collision is determined to have occurred. If ax1 is much less than ax2, a forward collision is determined to have occurred. If the accelerator pedal is not depressed, it is determined that a rearward collision has occurred; (3) When the acceleration in the x direction suddenly drops to ax1, the following judgments are performed depending on whether the brake pedal is pressed: If the brake pedal is pressed, the vehicle acceleration ax3 is calculated based on the brake position. If ax1 is much greater than ax3, a rear collision is determined to have occurred. If ax1 is much less than ax3, a forward collision is determined to have occurred. If the brake pedal is not depressed, a forward collision is determined to have occurred; A three-axis acceleration sensor is used to detect whether a collision occurs in the y direction of a typical vehicle coordinate system during vehicle driving, and is characterized in that the method includes the following steps: (1) Measure the acceleration ay in the y direction with a period T; (2) When the acceleration in the y direction suddenly increases to ay1, it is judged that a collision has occurred on the left side; (3) When the acceleration in the y direction suddenly drops to ay1, it is judged that a collision has occurred on the right side; A three-axis acceleration sensor is used to detect whether a collision occurs in the z direction of a typical vehicle coordinate system during vehicle driving, and is characterized in that the method includes the following steps: (1) Measure the acceleration az in the z direction with a period T; (2) When the acceleration in the z direction suddenly increases to az1, it is judged that a collision has occurred below; (3) When the acceleration in the z direction suddenly drops to az1, it is judged that a collision has occurred above; If the acceleration in the x, y or z direction at a certain moment obviously exceeds the historical average, it is considered that the acceleration in that direction has increased or decreased suddenly, and if it exceeds the average by 10%, it is considered that a mutation has occurred.

2. A vehicle collision detection method according to claim 1, characterized in that: The vehicle acceleration when the accelerator pedal is depressed is determined using a pre-calibrated setting.

3. A vehicle collision detection method according to claim 2, characterized in that: The vehicle acceleration when the brake pedal is depressed is determined using a pre-calibrated value.

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