JP3113041B2 - Collision judgment device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a collision judging device,
In particular, the present invention relates to a collision determination device that detects a collision of a vehicle and activates an occupant protection device.

[0002]

2. Description of the Related Art Conventionally, a safety device has been mounted on a vehicle to protect an occupant by inflating an airbag when the vehicle collides. In this safety device, a plurality of switch-type acceleration sensors are mounted on a vehicle to determine a collision and drive an airbag.

[0003]

Conventionally, as described above, a plurality of acceleration sensors are mounted on a vehicle to determine a collision.

[0004] It is an object of the present invention to provide a collision judging device which can judge a collision by one analog acceleration sensor mounted on a vehicle.

[0005]

In order to achieve the above object, according to the present invention, an acceleration sensor mounted on a vehicle, and a test pattern generator for outputting at least a waveform signal at the time of a collision during a test are provided. Inputting signals output from the acceleration sensor and the test pattern generator ,
And three or more collision determining means which are connected in parallel with each other, the three
A majority circuit that receives the results of the determination by the collision determination means or more , and a majority circuit that is connected to the majority circuit during the test ;
It is disconnected from the majority circuit at times other than during testing.
It is characterized in that it comprises an abnormality determination unit for determining an abnormality in the test result, and an alarm unit connected to the abnormality determination unit and activated when the abnormality determination unit determines that there is an abnormality.

[0006]

[0007]

According to the first aspect of the present invention, the G signal output from the acceleration sensor can be determined by a plurality of collision determining means, and the final decision can be made by a majority decision. Becomes possible. Also, test putter
A waveform signal at the time of collision is output from the
The operation of the collision judgment means can be checked.
it can.

[0008]

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 shows a functional block diagram of the present invention.

In FIG. 1, 1 is a G sensor mounted on a vehicle, and 2 is a signal waveform at the time of collision or non-collision (that is,
The test pattern generator 3 outputs a waveform signal at the time of collision and at the time of non-collision, and the test pattern generator 3 analyzes the G signal supplied from the G sensor 1 or the test pattern input from the test pattern generator 2. The CPU 4 for determining collision or non-collision is an airbag drive circuit that starts when a collision determination signal is obtained from the CPU 3.

Reference numeral 5 denotes an abnormality judging unit, which is connected to the majority decision circuit 37 when a test pattern waveform signal is output from the test pattern generating unit 2. The abnormality determination unit 5 determines that the collision is non-collision by the CPU 3 when the waveform signal at the time of collision is output from the test pattern generation unit 2, or determines the collision when the waveform signal at the time of non-collision is output. When it is determined that there is, it is determined to be abnormal. Reference numeral 6 denotes an alarm unit that is activated when the abnormality determination unit 5 determines that an abnormality has occurred.

The test pattern generating section 2 is provided with a signal waveform of a typical frontal collision as shown in FIG. 2 (a), or when traveling on a rough road as shown in FIG. 2 (b). The signal waveform of is output. This signal waveform is output from the test pattern generator 2 at the time of starting the vehicle, for example.

The CPU 3 has the following functions.
That is, it has first, second, and third collision determination algorithms 31, 32, and 33 that operate in parallel, and each of the collision determination algorithms 31, 32, and 33 analyzes an input signal and performs parallel analysis. The collision and the non-collision are determined. The determination results of the respective collision determination algorithms 31, 32, and 33 are output to selectors 34, 35, and 36, respectively.
Sent to The selectors 34, 35 and 36 select the judgment results a1, b1; a2, b2; a3, b3 output from the collision judgment algorithms 31, 32 and 33.

Here, a1, a2 and a3 are the G sensors 1
Determination signal when analyzing the G signal supplied from b1, b1,
b2 and b3 indicate determination signals when the test pattern supplied from the test pattern generator 2 is analyzed.

The output signals of the selectors 34, 35, 36 are sent to a majority circuit 37. The majority circuit 37 takes the majority of the determination signals from the selectors 34, 35 and 36 and determines collision or non-collision. When it is determined that a collision has occurred, a collision signal is output to the airbag drive circuit 4 or the abnormality determination unit 5.

Next, the first collision determination algorithm 3
One example will be described with reference to FIG.

G sensor 1 or test pattern generator 2
When a collision waveform is input from the controller (step S0 is affirmative), the input time t1 of the waveform is stored (step S0).
1) Then, a differential coefficient dg / dt of the signal waveform, that is, a gradient (gradient) is calculated (step S2). continue,
The correlation value of the dg / dt is calculated (step S
3). This correlation value is calculated, for example, as a correlation value “1” when there is a correlation, and as a correlation value “0” when there is no correlation, as compared with the differential coefficient dg / dt of the known collision G waveform at the same time. This correlation value RK is temporarily stored (step S4).

Next, the magnitude of the signal waveform, that is, G
A value is calculated (step S5). Next, a G level correlation value is calculated (step S6). In the same manner as described above, the correlation value is calculated by comparing the G value of the known collision G waveform at the same time with, for example, a correlation value “1” when there is a correlation, and a correlation value “0” when there is no correlation. Is done. This correlation value RG is temporarily stored (step S7).

Next, the process proceeds to step S 9, where t 1
The correlation values RK and RG from to t2 are integrated. Assuming that this integral value is S, it is determined in step S10 whether S ≧ α0 holds. That is, it is determined whether or not the integral value S has become equal to or greater than the predetermined reference value α0.

If this determination is affirmative, it is determined that the collision has occurred, and a signal of, for example, an H (high) level is output (step S11), and the process ends. On the other hand, if the determination is negative, it is determined that there is no collision, and for example, an L (low) level signal is output (step S12).

Subsequently, it is determined whether or not the time has reached t2 (step S8). If this determination is negative, the process returns to step S2, and the above operation is repeated.
When t = t2 (Yes at step S8), the process ends. Note that the time t1 to t2 is about 20 ms.

With the above processing, the analysis of the input signal is completed. Steps S2 to S4 are “tilt processing”,
Steps S5 to S7 are "G level processing", step S9
Can be called "integration processing" and step S10 can be called "comparison processing".

Next, an example of the second collision determination algorithm will be described with reference to FIG.

Next, proceeding to step S4, it is determined whether or not the integrated value of step S2 has become equal to or greater than a predetermined reference value β0. If this determination is affirmative, it is determined that a collision has occurred, for example, an H (high) level signal is output (step S5), and the process ends. On the other hand, if the determination is negative, it is determined that there is no collision, and for example, an L (low) level signal is output (step S6).

Next, proceeding to step S 3, it is determined whether a predetermined time t 4 (for example, 50 ms) has elapsed. If the determination is negative, the process returns to step S1 and the above operation is repeated. If the determination in step S3 is affirmative, the process ends.

Next, an example of the third collision determination algorithm will be described with reference to FIG. This algorithm is different from the second collision determination algorithm in step S1.
Is set to t5 (for example, 5 msec), and the predetermined time of step S3 is set to t6 (for example, 100 msec).
Second) and the point that the reference value in step S4 is γ0.

Next, the operation of one embodiment of the present invention will be described with reference to FIG.

When the vehicle is started, the test pattern generator 2 outputs a typical collision G signal as shown in FIG. 2 (a), for example. The collision G signal is input to the first to third collision determination algorithms 31 to 33 and analyzed. The result of this analysis is the judgment signals b1, b2, b3
Is output from each of the collision determination algorithms 31, 32, and 33. At this time, since the selectors 34, 35 and 36 have selected the decision signals b1, b2 and b3, the decision signals b1, b2 and b3 are sent to the majority decision circuit 37 through the selectors 34, 35 and 36. .

The majority circuit 37 determines the judgment signals b1, b2, b
Determine the collision or non-collision by taking the majority vote of 3. That is, two of the determination signals b1, b2, b3
If more than one was collision and less than one was non-collision, many
The collision is determined by the decision. On the other hand, the judgment signals b1, b
2, one or less of b3 is collision, and two or more are non-collision.
At times, it is determined that there is no collision by majority decision. The majority decision circuit 37 is connected to the abnormality determination unit 5. If the result of the determination is a collision, the first to third collision determination algorithms 31 to 33 are operating correctly.
Does not output any signal. Therefore, the alarm unit 6 does not operate.

However, if the result of the determination is that there is no collision, the first to third collision determination algorithms 31 to 33 are malfunctioning, and the abnormality determination unit 5 outputs an abnormal signal. As a result, the alarm unit 6 is activated and notified that the collision determination device is abnormal.

When the above check is completed, the test pattern generator 2 outputs a non-collision G signal as shown in FIG. 2B, for example. Then, a test similar to the above is performed. At this time, if the majority decision circuit 37 determines that there is no collision, the abnormality determination unit 5 does not output any signal because the first to third collision determination algorithms 31 to 33 are normal. Therefore, the alarm unit 6 does not operate.

However, when the majority decision circuit 37 determines that a collision has occurred, the abnormality determination section 5 outputs an abnormality signal, and the alarm section 6 operates.

When the above checks are completed and the first to third collision determination algorithms 31 to 33 are determined to be normal, the selectors 34 to 35 select the determination signals a1 to a3, and the majority decision circuit 37 It is connected to the airbag drive circuit 4. Then, the process shifts to monitoring of the G signal output from the G sensor 1.

When a G signal indicating a collision is output from the G sensor 1 while the vehicle is running, the first to third collision determination algorithms 31 to 33 operate normally and accurately determine that a collision has occurred. . As a result, a start signal is sent from the majority decision circuit 37 to the airbag drive circuit 4, and the airbag drive circuit 4 is started.

As described above, according to this embodiment, a plurality of collision determination algorithms are operated in parallel.

In the above embodiment, the selectors 34 to 36 are used.
The first to third collision determination algorithms 3
One to one of the output terminals 1 to 33 may be connected to the majority circuit 37.

[0037]

According to the present invention, even if one analog acceleration sensor is used, the collision is determined by majority decision using a plurality of collision determination algorithms, so that the collision can be determined. Further, more complicated control becomes possible.

Further, the plurality of collision determination algorithms can be checked.

[Brief description of the drawings]

FIG. 1 is a functional block diagram of one embodiment of the present invention.

FIG. 2 is a waveform chart showing an example of a waveform signal output by a test pattern generator.

FIG. 3 is a flowchart illustrating an example of a first collision determination algorithm.

FIG. 4 is a flowchart illustrating an example of a second collision determination algorithm.

FIG. 5 is a flowchart illustrating an example of a third collision determination algorithm.

[Explanation of symbols]

1. G sensor, 2. Test pattern generator, 3. CP
U, 4 ... airbag drive circuit, 5: abnormality determination section, 6: alarm section, 31, 32, 33 ... first, second, and third collision determination algorithms

Continuation of the front page (72) Inventor Toshio Asami 1-4-1 Chuo, Wako-shi, Saitama Prefecture Honda Technical Research Institute Co., Ltd. (56) References JP-A-3-238358 (JP, A) JP-A-3-246139 (JP, A) JP-A-5-124484 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B60R 21/32 G01P 15/00

Claims (2)

(57) [Claims] 1. An acceleration sensor mounted on a vehicle, a test pattern generator for outputting at least a waveform signal at the time of a collision at the time of a test, and a signal output from the acceleration sensor and the test pattern generator as inputs . Mutual
Three or more collision judging means connected in parallel , a majority decision circuit to which the judgment results of the three or more collision judging means are inputted, and a majority decision circuit connected to the majority decision circuit at the time of the test,
Test result when disconnected from the majority circuit
A collision determination device, comprising: an abnormality determination unit that determines an abnormality of the above; and an alarm unit that is connected to the abnormality determination unit and that is activated when the abnormality determination unit determines that the abnormality is abnormal. Wherein said test pattern generating section, the collision determination device according to claim 1, characterized in that so as to output the waveform signal at the waveform signal and the non-collision at the time of collision.