JP2006327370A - Start determination device for occupant crash protector of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a start determination device for an occupant crash protector of a vehicle capable of detecting an oblique impact state rapidly with high accuracy and determining the start only by right and left front sensors. <P>SOLUTION: The left front acceleration sensor signal LS is received by an integrator 12 through a high pass filter 11 arranged in an ECU 2 to calculate the velocity VL. Similarly, the right front acceleration sensor signal RS is received by an integrator 14 through a high pass filter 13 arranged in the ECU 2 to calculate the velocity VR. The similarity function is operated by a similarity function operation unit 15 from the signals of the velocity VL and VR, and when the output value exceeds the threshold in threshold determination units 20, 21, ignition is performed by an airbag ignitor and an airbag is operated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an activation determination device for a vehicle occupant protection device, and more particularly to an activation determination of a vehicle occupant protection device that detects an oblique collision or an offset collision of a vehicle with high reliability and performs activation determination in a short time. It relates to the device.

  A conventional activation determination device for an occupant protection device for a vehicle inputs acceleration outputs of a floor sensor, a left front sensor, and a right front sensor to a collision type determination unit via a signal input unit. Integrate the front sensor output detected by, and compare the output values of the left front sensor and right front sensor with the set threshold value, and the left and right front sensor values are integrated and output. Whether or not there is is determined (for example, see Patent Document 1).

JP 2002-29363 A (FIGS. 3 and 6)

  However, the conventional vehicle occupant protection device activation determination device as described above uses the floor sensor signal as a criterion for determining the initial state of the collision. There was a problem that occurred.

  The present invention has been made in order to solve the above-described problems, and an object of the present invention is to provide an activation determination device for a vehicle occupant protection device that can accurately determine the activation of an oblique collision without a floor sensor. And

  An activation determination device for a vehicle occupant protection device according to the present invention includes a left front acceleration sensor that detects a collision of a left front portion of a vehicle body, a right front acceleration sensor that detects a collision of a right front portion of the vehicle body, a left front acceleration sensor, The output value of the right front acceleration sensor is sampled and stored, the current sample value is arranged first with the data before (n−1) samples, and the respective sensor outputs are arranged as vectors xi, yi (i = 0 to ( n-1)), and a collision determination means for performing a collision determination on the result of normalizing these two vectors and calculating the inner product by exceeding a set threshold value.

  The activation determination device for a vehicle occupant protection device according to the present invention makes an accurate collision without using a floor sensor by determining by using a similarity function that indicates how similar two vectors of the left and right front acceleration sensor signals are. It is possible to obtain an effect that the activation determination can be performed.

Embodiments of the present invention will be described below with reference to FIGS.
Embodiment 1 FIG.
FIG. 1 is an explanatory diagram showing the configuration of a start determination device for a vehicle occupant protection device according to Embodiment 1 of the present invention.
In the figure, an electric control unit (hereinafter referred to as ECU) 2, an ECU acceleration sensor (central acceleration sensor) 3, a left front acceleration sensor 4, as a control means for performing airbag deployment processing on the vehicle body 1, The right front acceleration sensor 5 is mounted, the left front acceleration sensor 4 and the ECU 2 are connected by a left front acceleration sensor communication cable 6, and the right front acceleration sensor 5 and the ECU 2 are connected by a left front acceleration sensor communication cable 7. The Note that the direction representing the overall length of the vehicle body 1 is the X direction, the direction representing the vehicle width of the vehicle body 1 is the Y direction, and the vertical direction representing the vehicle height of the vehicle body 1 is the Z direction. Note that the ECU 2 as the control unit also serves as a collision determination unit.

  The ECU 2 is mounted in the vicinity of the seat on which the driver in the center of the vehicle body 1 is boarded, and includes an ECU acceleration sensor 3. The ECU acceleration sensor 3 detects the acceleration of the vehicle body 1 in the X direction. It is mounted on the printed circuit board. Further, a left front acceleration sensor 4 is attached in the vicinity of the left headlamp at the front portion of the vehicle body 1 so as to detect the acceleration in the X direction of the vehicle body 1.

  Similarly, a right front acceleration sensor 5 is attached in the vicinity of the right headlamp at the front portion of the vehicle body 1 so as to detect the acceleration of the vehicle body 1 in the X direction. The detection signal of the left front acceleration sensor 4 is input to the ECU 2 via the left front acceleration sensor communication cable 6, and the detection signal of the right front acceleration sensor 5 is input to the ECU 2 via the right front acceleration sensor communication cable 7. Is input. Further, a passenger seat airbag 8 that protects the passenger on the passenger seat from the impact of the collision and a driver seat airbag 9 that protects the driver from the impact of the collision are mounted in the passenger compartment of the vehicle body 1.

FIG. 2 is a block diagram showing an example of a specific circuit configuration of the ECU 2 in the activation determination device for an occupant protection device according to Embodiment 1 of the present invention.
In the figure, the activation determination device integrates the high-pass filter (HPF) 11 to which the left front acceleration sensor signal LS from the left front acceleration sensor 4 in FIG. 1 is input and the output of the high-pass filter 11 to obtain the speed VL. An integrator 12, a high-pass filter (HPF) 13 to which the right front acceleration sensor signal RS from the right front acceleration sensor 5 of FIG. 1 is input, and an integrator 14 that integrates the output of the high-pass filter 13 to obtain the speed VR. A similarity function calculation unit 15 that calculates a similarity function based on the signals relating to the speed VL from the integrator 12 and the speed VR from the integrator 14, and a low-pass filter (LPF) provided on the output side of the similarity function calculation unit 15 ) 16, the absolute value calculation unit 17 for obtaining the absolute value of the speed VL from the integrator 12, and the speed V from the integrator 14 An absolute value calculation unit 18 for obtaining the absolute value of the output value, a determination unit 19 for performing OR operation on the output of the absolute value calculation unit 17 and the output of the absolute value calculation unit 18, and comparing and determining the output value of the low-pass filter 16 and the threshold value α. The threshold value determination unit 20, the threshold value determination unit 21 that compares and compares the output value of the determination unit 19 and the threshold value β, and the output of the threshold value determination unit 20 and the output of the threshold value determination unit 21 are AND-processed to perform an airbag ignition device ( And a determination unit 22 for outputting to a not-shown).

Next, the operation will be described first with reference to the flowchart of FIG.
In step ST1, a left front acceleration sensor signal is input from the left front acceleration sensor 4. In step ST2, the signal is passed through a high-pass filter 11 that suppresses a low-frequency drift component disposed in the ECU 2. In step ST3, the integrator 12 A speed VL is calculated. Similarly, in step ST4, a right front acceleration sensor signal is input from the right front acceleration sensor 5, and in step ST5, the high-pass filter 13 that suppresses a low-frequency drift component that is also disposed in the ECU 2 is used. In step ST6, The integrator VR calculates the velocity VR.

  Next, in step ST7, the similarity function calculation unit 15 performs similarity function calculation processing from the signals related to the speed VL and the speed VR, and the absolute value calculation units 17 and 18 calculate absolute values from the signals related to the speed VL and the speed VR. The determination unit 19 performs an OR operation on the output. In step ST8, the threshold value determination unit 20 makes a comparison between the output value supplied from the similarity function calculation unit 15 through the low-pass filter 16 and the threshold value α. The threshold value determination unit 21 makes a comparison determination between the output value of the determination unit 19 and the threshold value β, and determines whether each output value exceeds the threshold value. In step ST8, if both output values exceed the threshold values in the AND operation process in the determination unit 22, an air bag ignition device (not shown) is ignited in step ST9. A bag (not shown) is activated.

  On the other hand, if each output value does not exceed the threshold value in step ST8, the process returns to steps ST1 and ST4 and the above-described operation is repeated. That is, if each output value does not exceed the threshold value in step ST8, the left and right front acceleration sensor signals for the next time are taken and sampled repeatedly.

2 will be described in detail with reference to FIGS.
After the left front acceleration sensor signal from the left front acceleration sensor 4 suppresses the low frequency drift component through the high pass filter 11 disposed in the ECU 2, the speed VL is calculated by the integrator 12. Similarly, the right front acceleration sensor signal from the right front acceleration sensor 5 suppresses the low frequency drift component through the high pass filter 13 disposed in the ECU 2, and then the speed VR is calculated by the integrator 14. The similarity function calculation unit 15 calculates a value γxy indicating similarity from the signals of the speeds VL and VR. The value γxy indicating the similarity is supplied to the threshold determination unit 20 after reducing unnecessary high-frequency noise through the low-pass filter 16, and when the threshold α set by the threshold determination unit 20 is exceeded, the logical value “1” is set. Otherwise, the logic value “0” is output.

  On the other hand, the absolute value of the calculated value of the left speed VL is calculated by the absolute value calculating unit 17, and the absolute value of the calculated value of the right speed VR is calculated by the absolute value calculating unit 18. 19, the determination unit 19 outputs the value Vmax having the larger VL or VR speed to the threshold determination unit 21, and the threshold determination unit 21 receives the input value exceeding a preset threshold β. A logical value “1” is output, otherwise a logical value “0” is output.

  Finally, the determination unit 22 performs an AND operation process on the output value of the threshold determination unit 20 and the output value of the threshold determination unit 21. When both output values are logical values “1”, the determination unit 22 outputs a logical value “1”, an ignition signal is applied to an airbag ignition device (not shown), and the airbag is activated.

The similarity function calculation in the similarity function calculation unit 15 is calculated by the method described below. Let t be the current time, and let the sample value of the left front acceleration sensor signal at this time be represented by x (t). When sampling is performed at the period Δt, the value before (n−1) samples is x (t− (n−1) Δt). When n values are stored in the memory retroactively from the current time, they are expressed as follows when expressed as a vector x _n .

同様に、右側フロント加速度センサ信号についてｎ個の値をメモリ（図示せず）に蓄えるとき、これらのベクトルy_nとすると、以下のように表される。

図４にメモリ（図示せず）に蓄えられたデータ配列を示す。

Similarly, when n values of the right front acceleration sensor signal are stored in a memory (not shown), _assuming these vectors yn, they are expressed as follows.

FIG. 4 shows a data array stored in a memory (not shown).

ここで、Ｇ_xy、Ｇ_xx、Ｇ_yy は次式で表される。

A function γ _xy = f (x _n , y _n ) indicating the similarity between two vectors x _n and y _n is given by the following equation.

Here, G _xy, G _{xx, and} G _yy are expressed by the following equations.

  The similarity function calculation represents the inner product of normalized vectors. Since the low-frequency component is suppressed by the high-pass filters 11 and 13, the value becomes 0 when the left and right waveforms are similar, and the value becomes large when they are not similar. For example, the solid line in FIG. 5A is a value obtained by integrating the left front acceleration sensor signal representing the oblique waveform through the high-pass filter 11 and then integrating with the integrator 12 to obtain the speed VL. It can be seen that the speed is greatly increased due to the left side oblique projection. On the other hand, the dotted line in FIG. The speed is not so great, and the overall waveform is gentle.

  Further, the solid line in FIG. 5B is a value obtained by integrating the right front acceleration sensor signal representing the oblique waveform through the high-pass filter 13 and then integrating with the integrator 14 to obtain the velocity VR. Because of the left-side oblique projection, the initial speed is small and gradually increases. On the other hand, the dotted line in FIG. 5B represents a straight waveform, which is not so different from the speed calculation result of the left front acceleration sensor 4.

  FIG. 5C shows a similarity function calculation result in the similarity function calculator 15. The solid line indicates the oblique collision, but it can be seen that the oblique collision can be determined because the right and left velocity waveforms do not resemble at the initial stage of the collision and rise rapidly. In the latter half of the collision, the waveform approaches 0 because there is no sudden change in waveform. On the other hand, since there is not much difference between the left and right waveforms in the case of a normal collision, the value is close to 0 although not shown in the figure, and it is determined that there is no oblique collision.

FIG. 6 is an explanatory diagram illustrating a collision mode that is a target of a collision determination performed by the activation determination device for the occupant protection device according to the first embodiment.
FIG. 6A shows a frontal collision in which the vehicle body 1 collides with the wall-shaped rigid body 30 from the front. FIG. 6B shows an Offset Rigid Barrier (hereinafter referred to as ORB) collision in which either the left or right half of the front portion of the vehicle body 1 collides with a rigid body 30 shaped like a concrete block. . FIG. 6C shows rough road running. FIG. 6D shows an underride collision in which, for example, the vehicle body 1 enters under the large truck when it collides with a rigid body 30 such as concrete or a large truck.

  FIG. 6 (e) shows a pole protrusion that collides from the front with a pole 31 such as a cylindrical power pole having rigidity. FIG. 6F shows an offset pole projection in which a pole 31 such as a utility pole collides with the left or right from the center of the vehicle body 1. FIG. 6G shows an oblique projection in which the vehicle body 1 obliquely collides with a rigid body 30 such as a concrete wall. FIG. 6 (h) shows an Offset Deformable Barrier (hereinafter referred to as ODB) in which the vehicle body simulation 32 such as an aluminum honeycomb that has run opposite to the opposite lane (softer than a wall or the like) and the front part of the vehicle collide head-on. ) Indicates a collision. FIG. 6 (i) shows an animal collision that collides head-on with a large animal 33 such as a cow or horse.

  The activation determination device for the vehicle occupant protection device according to the present embodiment includes the ORB in FIG. 6B, the offset pole protrusion in FIG. 6F, the oblique protrusion in FIG. 6G, and the ODB in FIG. It works effectively for collision detection.

FIG. 7 collectively shows the characteristics of the waveforms of the respective collision modes.
As can be seen from this, (c) the acceleration waveforms detected by the left front acceleration sensor 4 and the right front acceleration sensor 5 provided at the front portion of the vehicle body 1 for the offset pole protrusion, the oblique protrusion, and the ODB protrusion are the collision side It can be seen that the waveform becomes larger and a large difference between the left and right occurs. The activation determination device for a vehicle occupant protection device according to the first embodiment determines the collision mode by utilizing the difference between the left and right waveforms at the beginning of the collision.

As described above, according to the first embodiment, the similarity between the outputs of the right front acceleration sensor 4 and the left front acceleration sensor 5 on the vehicle body 1 by the acceleration waveform generated when the vehicle body 1 obliquely projects. Therefore, it is possible to determine the oblique projection, so that the deployment of the airbag can be controlled accurately.
In addition, by judging by the vector similarity function (inner product of normalized vectors) indicating how similar the two vectors of the left and right back acceleration sensor signals are, the ECU can start the oblique collision with high accuracy without using the floor sensor. Judgment can be made.

Embodiment 2. FIG.
FIG. 8 is an explanatory diagram showing the configuration of the activation determination device for a vehicle occupant protection device according to Embodiment 2 of the present invention. In addition, the same code | symbol is attached | subjected to the part which is the same as that of what was shown in FIG. 1, or is equivalent, and the description is abbreviate | omitted.
In the present embodiment, as in FIG. 1, the ECU 2, the ECU acceleration sensor 3, the left front acceleration sensor 4, and the right front acceleration sensor 5 are mounted on the vehicle body 1, and the left front acceleration sensor 4 and the ECU 2 are for the left front acceleration sensor. In addition to being connected by the communication cable 6 and the right front acceleration sensor 5 and the ECU 2 being connected by the left front acceleration sensor communication cable 7, in the present embodiment, the left back acceleration sensor 40 and the right back acceleration sensor 41 are Mounted on the vehicle body 1, the left back acceleration sensor 40 and the ECU 2 are connected by a left back acceleration sensor communication cable 42, and the right back acceleration sensor 41 and the ECU 2 are connected by a right back acceleration sensor communication cable 43.

  Although not shown in the vehicle body 1 shown in FIG. 8, a passenger's seat airbag 8 and a driver's seat airbag 9 are provided in the same manner as that shown in FIG. Further, similarly to the vehicle body 1 shown in FIG. 1, the direction representing the entire length of the vehicle body 1 is the X direction, the direction representing the vehicle width of the vehicle body 1 is the Y direction, and the vertical direction representing the vehicle height of the vehicle body 1 is the Z direction. Assume that

  As described above, the activation determination device for the occupant protection device according to the second embodiment includes the vehicle body 1 in the configuration including the left front acceleration sensor 4, the right front acceleration sensor 5, and the ECU acceleration sensor 3 described in the first embodiment. A left-side back acceleration sensor 40 and a right-side back acceleration sensor 41 that detect acceleration in the X direction are added to the rear portion.

  Further, the ECU 2 used in the activation determination device for the passenger protection device according to the second embodiment is similar to the ECU 2 of the first embodiment shown in FIG. 2 in that the high-pass filter 11 to which the left front acceleration sensor signal is input, the integrator 12, the right front High-pass filter 13 to which the acceleration sensor signal is input, integrator 14, similarity function calculation unit 15, low-pass filter 16, absolute value calculation units 17 and 18, determination unit 19 by OR operation, threshold determination units 20 and 21, and AND operation A determination unit 22 is provided.

Next, the operation will be described.
The activation determination device for an occupant protection device according to the second embodiment inputs signals indicating left and right back accelerations detected by the left back acceleration sensor 40 and the right back acceleration sensor 41 to the ECU 2 and outputs the left front acceleration sensor 4 or the right front acceleration sensor 4. Calculation processing is performed in the same manner as the left and right front accelerations detected by the acceleration sensor 5, and the activation determination of the passenger seat airbag 8 and the driver seat airbag 9 is performed. Here, a detailed description of the operation performed in the same manner as the processing operation of the ECU 2 described in the first embodiment is omitted.

  As described above, according to the second embodiment, the left front acceleration sensor 4 and the right front acceleration sensor 5 are disposed at the front portion of the vehicle body 1, the ECU acceleration sensor 3 is disposed at the vehicle body center portion, and the left portion is disposed at the vehicle body rear portion. Since the back acceleration sensor 40 and the right back acceleration sensor 41 are provided, not only the front oblique projection but also the rear oblique projection of the vehicle body 1 can be accurately detected at high speed, and the airbag deployment can be accurately controlled.

It is explanatory drawing which shows the structure of the starting determination apparatus of the passenger | crew protection device of the vehicle by Embodiment 1 of this invention. It is a block diagram which shows the structure of the principal part of the starting determination apparatus of the passenger | crew protection apparatus by Embodiment 1 of this invention. It is a flowchart for demonstrating operation | movement of the starting determination apparatus of the passenger | crew protection apparatus by Embodiment 1 of this invention. It is a figure showing the left front acceleration sensor vector and right front acceleration sensor vector by Embodiment 1 of this invention. It is a figure which shows an example of the calculation result of the speed and similarity function calculated from the left-right front sensor by Embodiment 1 of this invention. It is explanatory drawing for demonstrating the collision form used as the object of the collision determination which the starting determination apparatus of the passenger | crew protection apparatus by Embodiment 1 of this invention performs. It is a table | surface figure which shows collectively the comparison result of the waveform illustrated for every collision form by Embodiment 1 of this invention. It is explanatory drawing which shows the structure of the starting determination apparatus of the passenger | crew protection device of the vehicle by Embodiment 2 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Car body, 2 ECU, 3 ECU acceleration sensor, 4 Left front acceleration sensor, 5 Right front acceleration sensor, 6 Left front acceleration sensor communication cable, 7 Right front acceleration sensor communication cable, 8 Passenger seat airbag, 9 Driver's seat Airbag, 11, 13 High-pass filter (HPF), 12, 14 Integrator, 15 Similar function calculation unit, 16 Low-pass filter (LPF), 17, 18 Absolute value calculation unit, 19 Determination unit by OR operation, 20, 21 Threshold Determination unit, 22 AND operation determination unit, 30 rigid body, 31 cylindrical column, 32 body simulation, 33 large animal, 40 left back acceleration sensor, 41 right back acceleration sensor, 42 communication cable for left back acceleration sensor, 43 right side Communication cable for back acceleration sensor.

Claims (4)

A left front acceleration sensor for detecting a collision of the left front part of the vehicle body,
A right front acceleration sensor for detecting a collision of the right front part of the vehicle body,
And a collision determination means for performing a collision determination by exceeding a set first threshold based on a result of calculating a similarity between the left front acceleration sensor and the right front acceleration sensor. Activation determination device for vehicle occupant protection device.   The collision determination means samples and stores the output values of the left front acceleration sensor and the right front acceleration sensor, and arranges the current sample values first (n−1) data before the sample last, 2. When the sensor output is represented by a vector xi, yi (i = 0 to (n−1)), the collision determination is performed based on a result obtained by normalizing these two vectors and calculating an inner product. An activation determination device for the vehicle occupant protection device according to claim.   The collision determination means, as a result of integrating the output value of the left front acceleration sensor and the output value of the right front acceleration sensor, has collided when the larger integrated value exceeds a set second threshold value. The start determination device for an occupant protection device for a vehicle according to claim 1, wherein the determination is made.   A left back acceleration sensor for detecting a collision of the vehicle body left back portion, a right back acceleration sensor for detecting a collision of the vehicle body right back portion, a center acceleration sensor provided at the center of the vehicle body, the left back acceleration sensor and the right back Each output value of the acceleration sensor is sampled and stored, and the current sample value is arranged first with the data before (n−1) samples, and the respective sensor outputs are represented by vectors xi, yi (i = 0 to (n And (1)) a collision determination means for performing a collision determination by exceeding a set threshold based on a result obtained by normalizing the two vectors and calculating an inner product. The start determination apparatus of the passenger | crew protection device of the vehicle in any one of 1-3.

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