JPH09277901A - Collision determination value deciding device and method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lower cost and shorten lead time when a collision determination value is decided. SOLUTION: A hammer 42 knocks a grille guard 24 part in a vehicle 20. An acceleration sensor 44 measures an impact added on the hammer 42 by this knock as acceleration so as to input it as an acceleration signal a1 into an arithmetic processing unit 46. An acceleration sensor 38 measures an impact, which is added on the vehicle 20 by this knock and is transmitted inside the vehicle 20, as acceleration so as to input it as an acceleration signal a2 into the arithmetic processing unit 46. The arithmetic processing unit 46 decides a new collision determination value on the basis of the acceleration signals a1, a2, and a collision determination value stored in a EEPROM 40 in a protection device ECU 28 is rewritten to the newly decided collision determination value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a collision determination value for determining a collision determination value used for determining whether or not a passenger protection device mounted in a vehicle is activated when the vehicle collides. The present invention relates to a determination device and a method thereof.

[0002]

2. Description of the Related Art In recent years, a vehicle has been equipped with an occupant protection device such as an airbag device or a seat belt device with a preloader for the purpose of protecting an occupant in the event of a vehicle collision.
Such an occupant protection device is an electronic control device (Electronic control device) when a large impact is applied to the vehicle due to a vehicle collision.
It is started by a control unit (hereinafter referred to as ECU).

In general, an ECU for a protective device is a ROM (Read O) for storing a sensor for measuring an impact applied to a vehicle (for example, an acceleration applied to the vehicle) and a collision determination value.
nlyMemory) and a CPU (Cen that performs various calculations and controls)
tral Processing Unit) etc. this house,
The CPU compares the measured value obtained by the sensor (or the calculated value obtained by arithmetically processing the measured value) with the collision determination value (that is, the threshold value) stored in the ROM, and according to the magnitude relation, Determine whether to activate the occupant protection device.

By the way, when the rigidity of the vehicle is changed (for example, attachment of a retrofit component such as a grill guard or a winch to the vehicle), the impact measured by the sensor with respect to the impact on the vehicle is Since the rigidity is different from that before the change, the collision determination value needs to be changed. Therefore, in the prior art, for example, as described in JP-A-6-316248, an EEPROM (Electrically Erasable) which is a ROM in which the collision determination value can be rewritten in advance.
When the vehicle rigidity is changed and stored in the programmable ROM), the collision determination value stored in the EEPROM is rewritten to the newly determined collision determination value to match the vehicle rigidity change. The collision judgment value was also changed.

[0005]

However, the above-mentioned publication does not particularly describe how to determine a new collision determination value when the rigidity of the vehicle is changed.

Generally, when the rigidity of the vehicle is changed, a new collision determination value is obtained by a collision test.
In other words, a test vehicle with the same rigidity change is used to actually cause a collision, the impact on the test vehicle at that time is measured, and the collision judgment value is determined based on the measured value. are doing.

However, in the method of obtaining the collision determination value by such a collision test, the test vehicle is seriously damaged by the collision and cannot be used again. Therefore, an expensive test vehicle is required every time the collision test is performed. There is a problem that it is necessary to prepare it, and therefore, it costs a lot of money. Also,
Since the collision test requires a considerable amount of work time, there is also a problem that the lead time until the collision judgment value is determined becomes long.

By the way, as described above, when it is necessary to change the collision determination value, it is not limited to the case where the rigidity of the vehicle is changed by, for example, attaching a retrofit component to the vehicle. For example, even when the rigidity of the vehicle is deteriorated due to secular change due to long-term use or a slight collision accident, the collision determination value needs to be changed. Therefore, even in such a case, the same problem as described above occurs.

Therefore, it is an object of the present invention to provide a collision determination value determination device and method capable of solving the above-mentioned problems of the prior art and reducing the cost and the lead time.

[0010]

In order to achieve at least a part of the above-mentioned object, a first aspect of the present invention determines whether or not to activate an occupant protection device in a vehicle at the time of a vehicle collision. A collision determination value determination device for determining a collision determination value used to perform a collision determination value, and a shock addition means for applying a shock to a specific portion of the vehicle to an extent that does not deform the vehicle; Propagation impact measurement means for measuring the impact propagating in the vehicle at a position different from the specific portion in the vehicle, and determining the collision determination value based on the measurement value obtained by the propagation impact measurement means. And a collision determination value determining means for performing the determination.

As described above, according to the first aspect of the invention, the impact applied to the specific portion of the vehicle by the impact applying means and propagating in the vehicle is measured by the propagating impact measuring means, and the collision is based on the obtained measurement value. The determination value is determined by the collision determination value determination means.

Therefore, according to the first aspect of the present invention, since the impact adding means only applies an impact to the vehicle so as not to deform the vehicle, the vehicle can be reused, thereby reducing the cost. You can Further, since the working time is short, the lead time until the collision determination value is determined can be shortened.

Further, in the collision determination value determination device of the first invention, it is preferable that the impact applying means includes impacting means for impacting the specific portion of the vehicle and applying the impact to the specific portion.

When such a striking means is provided, only a specific part of the vehicle is struck, so that even if the specific part is damaged by the striking, if only that part is replaced, the vehicle can be reused. Will be possible.

Further, in the collision determination value determination device of the first invention, the impact applying means includes a vibrating means for applying a predetermined vibration to the specific portion of the vehicle to apply the impact to the specific portion. It is preferable.

When such a shock applying means is provided,
Since only the specific portion of the vehicle is vibrated, the specific portion is not deformed and the vehicle can be reused.

Further, in the collision determination value determination device of the first invention, it is preferable that the impact applying means is mounted on the vehicle.

By mounting the impact adding means on the vehicle, it is possible to determine the collision determination value only within the vehicle without attaching another device to the vehicle.

Further, in the collision determination value determination device of the first invention, the collision determination value is further provided with additional impact measurement means for measuring the impact applied to the specific portion of the vehicle by the impact application means. It is preferable that the determining means determines the collision determination value based on the measured value obtained by the propagation impact measuring means and the measured value obtained by the additional impact measuring means.

Thus, not only the measured value of the shock propagating in the vehicle measured by the propagating shock measuring means, but also the measured value of the shock applied to the specific portion measured by the additional shock measuring means are taken into consideration. By determining the collision determination value, it is possible to more accurately determine the collision determination value.

In the collision determination value determination device of the first aspect of the invention, it is preferable that the specific portion of the vehicle is a retrofit component portion retrofitted to the vehicle.

In this way, when the rigidity of the vehicle is changed by attaching the retrofitting parts to the vehicle, the postfitting parts are made to be the specific parts to which the shock is applied by the shock applying means, so that the effects of the postfitting parts are included. Then, the collision judgment value can be determined.

In the collision determination value determination device of the first aspect of the invention, the collision determination value determination means is mounted in the vehicle and stores a plurality of values, and based on the measured value, It is preferable to include a selection unit that selects a desired value from the plurality of values stored in the storage unit and determines the value as the collision determination value.

In the collision determination value determination device of the first invention, the collision determination value used in the vehicle when the collision determination value is newly determined by the collision determination value determining means, It is preferable to further include a replacement unit that replaces the newly determined collision determination value.

For example, even when the collision determination value is newly determined due to the change in the rigidity of the vehicle, the collision determination value used until then is replaced with the newly determined collision determination value. It is possible to guarantee an accurate activation determination for the occupant protection device.

A second aspect of the present invention is a collision determination value determining method for determining a collision determination value used to determine whether or not to activate the passenger protection device in the vehicle at the time of a vehicle collision,
(A) applying an impact to a specific portion of the vehicle to such an extent as not to deform the vehicle; (b) measuring the impact applied to the vehicle and propagating in the vehicle; and (c).
And a step of determining the collision determination value based on the measurement value obtained in the step (b).

As described above, according to the second aspect of the invention, an impact that does not deform the vehicle is applied to a specific portion of the vehicle, the impact that is applied to the vehicle and propagates in the vehicle is measured, and the obtained measured value is obtained. The collision judgment value is determined based on.

Therefore, also in the second invention, the cost and the lead time can be shortened as in the first invention.

A third aspect of the present invention is a collision determination value determination method for determining a collision determination value used to determine whether or not to activate the passenger protection device in the vehicle at the time of vehicle collision.
(A) applying an impact to a specific portion of the vehicle to an extent that does not deform the vehicle; (b) measuring the impact applied to the specific portion of the vehicle; and (c) the vehicle. A step of measuring the impact that is applied to the vehicle and propagating in the vehicle; and (d) the collision based on the measurement value obtained in the step (b) and the measurement value obtained in the step (c). The gist is to provide a step of determining a judgment value.

As described above, according to the third aspect of the present invention, a shock is applied to a specific portion of the vehicle to such an extent that the vehicle is not deformed, and the shock applied to the specific portion and the shock propagating in the vehicle are measured, The collision determination value is determined based on the obtained measured values.

Therefore, according to the third aspect of the invention, not only the measured value of the shock propagating in the vehicle but also the measured value applied to the specific portion is taken into consideration to determine the collision determination value, so that the collision determination value is more accurate. It is possible to determine the collision determination value.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below based on Examples. FIG. 1 is a configuration diagram showing a collision determination value determination device as one embodiment of the present invention. In this embodiment, a case where the collision determination value is changed when the rigidity of the vehicle is changed (for example, a retrofit component such as a grill guard is attached to the vehicle) will be described. As shown in FIG. 1, this collision determination value determination device mainly includes a protective device ECU 28 mounted in the central portion of the vehicle 20, an arithmetic processing device 46 provided outside the vehicle 20, a hammer 42, Composed of.

A bumper 26 is attached to a front portion of a body 22 of the vehicle 20, and a grill guard 24 is attached by retrofitting as will be described later. On the other hand, the hammer 42, which is the impact applying means, is provided with an acceleration sensor 44, which is the additional impact measuring means, at the hitting portion.

FIG. 2 is an enlarged view showing the protective device ECU 28 of FIG. 1 in an enlarged manner. As shown in FIG. 2, the protective device ECU 28 includes an acceleration sensor 38 that is a propagation impact measuring unit that measures acceleration applied to the vehicle 20, a CPU 36 that performs various calculations and controls, and a collision determination value E
An EPROM 40 is mainly provided, and these are housed in the case 30.

The case 30 has a bracket 32 on its bottom surface.
Are fixed by welding and are supported by the bracket 32. The leg portion of the bracket 32 is the vehicle 20.
It is fixed to the body 22 by screws. Case 3
0 and the entire bracket 32 are housed in a box as shown in FIG.

As shown in FIG. 2, in the case 30, the acceleration sensor 38 is provided on the side wall and the printed circuit board 3 is provided on the lower surface.
4 are fixed by screws. Of these, the printed circuit board 34 has a CPU 36 and an EEPROM.
In addition to 40, a processing circuit (not shown) is provided, and the output signal line of the acceleration sensor 38 is further connected.

The acceleration sensor 38 constantly measures the acceleration applied to the vehicle 20 while the vehicle is running, and inputs the obtained measured value to the CPU 36 via the processing circuit. CPU3
Reference numeral 6 performs arithmetic processing such as integration on the input measured value to obtain an arithmetic value, and also reads a collision determination value from the EEPROM 40. Then, the obtained calculated value is compared with the read collision determination value, and it is determined whether or not an occupant protection device (not shown) such as an airbag device is to be activated depending on the magnitude relationship. That is, when a vehicle collision occurs, the calculated value exceeds the collision determination value, and therefore the occupant protection device is activated based on that.

Now, the grill guard 24 is attached to the vehicle 20.
Let's consider the case of retrofitting and changing the rigidity of the vehicle. As described above, when the rigidity of the vehicle is changed, the collision determination value needs to be changed accordingly. Therefore, in order to obtain a new collision determination value, the following method is used in this embodiment.

First, as shown in FIG. 1, the grill guard 2
A vehicle 20 in which 4 is attached to the front of the body 22 is prepared (hereinafter, a vehicle equipped with such a grill guard may be referred to as a vehicle with a grill guard), and the protective device ECU 28 and the arithmetic processing device 46 are provided. The hammer 42 and the arithmetic processing unit 46 are connected by signal lines. Therefore, the protective device ECU 28 and the hammer 42 are each provided with a connector (not shown) for connecting a signal line.

Next, the hammer 42 strikes the grill guard 24 portion of the vehicle 20. Due to this impact, a mechanical shock (that is, a shock force or a shock wave) is applied to the hammer 42, and the shock is measured by the acceleration sensor 44 as acceleration. The measurement result is input to the arithmetic processing unit 46 as the acceleration signal a1. here,
According to the law of action / reaction of force, it is considered that the impact applied to the hammer 42 is almost the same as the impact applied to the struck part of the vehicle 20 (that is, the contact part of the grill guard 24 with the hammer 42). Therefore, the acceleration sensor 44
Can be considered as measuring the impact on the struck part of the vehicle 20.

Further, the impact causes the vehicle 20 to be impacted. The shock propagates through the grill guard 24 and the body 22 in order, and further, via the bracket 32 of the protective device ECU 28 and the case 30, the acceleration sensor 38.
And is measured by the acceleration sensor 38 as acceleration. The measurement result is input to the arithmetic processing unit 46 as the acceleration signal a2.

FIG. 3 is a block diagram showing the configuration of the arithmetic processing unit 46 shown in FIG. As shown in FIG. 3, the arithmetic processing unit 46 includes amplifiers 50 and 52, filters 54 and 56, integration circuits 58 and 60, integration value calculation circuits 62 and 64, integration value ratio calculation circuit 66, correction coefficient calculation circuit 68, and A collision determination value calculation circuit 70 is provided.

The acceleration signal a1 input from the hammer 42 to the arithmetic processing unit 46 is amplified by the amplifier 50, filtered by the filter 54, integrated by the integrating circuit 58, and converted into the velocity signal v1. In addition, E for protection device
Similarly, the acceleration signal a2 input from the CU 28 to the arithmetic processing unit 46 is also amplified by the amplifier 52 and the filter 56.
After being filtered by, the signal is integrated by the integrating circuit 60 and converted into the velocity signal v2.

FIG. 4 is a characteristic diagram showing an example of temporal changes of the acceleration signals a1 and a2 and the velocity signals v1 and v2 of FIG. In FIG. 4, (a) is the acceleration signal a1, (b)
Is the velocity signal v1, (c) is the acceleration signal a2, (d)
Indicate the changes over time of the speed signal v2.

Next, the speed signal v1 from the integrating circuit 58 is sent to the integrated value calculating circuit 62, and the speed signal v2 from the integrating circuit 60 is sent to the integrated value calculating circuit 64 at the time of impact (ie, 0 second). ) To t1 seconds, the integrated values G1 and G2 are obtained. Here, the time t1 is, for example, a time at which it is absolutely necessary to determine whether or not to activate the occupant protection device by at least the time after the vehicle collision occurs. Further, the integrated values G1 and G2 correspond to the areas of the shaded portions shown in FIGS. 4 (b) and 4 (d).

The integrated values G1 and G obtained as described above
Both 2 are input to the integrated value ratio calculation circuit 66, and the ratio G2 / G1 of the two is calculated there.

Next, the grill guard 24 is removed from the vehicle 20 with the grill guard hit earlier (hereinafter, a vehicle without such a grill guard may be referred to as a standard vehicle), and this time, the bumper 26. The part is hit with a hammer 42. And at this time, hammer 4
The impact applied to the vehicle 2 and the impact applied to the vehicle 20 are measured by the respective acceleration sensors 44 and 38 as in the previous case. The result obtained by the measurement is processed by the same processing path as before, and finally, in the integrated value ratio calculation circuit 66,
The integral value ratio G2 / G1 is also obtained for the standard vehicle.

FIG. 5 shows integral values G1, G2 and integral value ratio G1 / G obtained for a standard vehicle and a vehicle with a grill guard.
It is explanatory drawing which shows the magnitude relationship of 2. As shown in FIG.
In the case of a standard vehicle, the impact applied by the hammer 42 is applied to the body 22, the bracket 32, and the case 3
Since it is gradually attenuated while propagating 0, the integrated value G2 becomes small. On the other hand, in the case of a vehicle with a grill guard, after the impact passes through the grill guard 24, the body 22,
The shock is further attenuated by the grill guard 24 because it propagates through the bracket 32 and the case 30, and the integrated value G2
Is minimal. On the other hand, since the impact applied to the hammer 42 is almost the same in both the standard vehicle and the vehicle with the grill guard, the integrated value G1 is large in any case.

Therefore, the integrated value ratio G2 / G1 is small in the case of the standard vehicle, but is extremely small in the case of the vehicle with the grill guard.

Next, in the correction coefficient calculation circuit 68 shown in FIG. 3, the integral value ratio G1 / G2 obtained for the vehicle with the grill guard and the integral value ratio G1 obtained for the standard vehicle.
/ G2, a collision correction coefficient K for determining a new collision determination value is obtained according to the following equation.

[0051]

[Equation 1]

Subsequently, the collision determination value calculation circuit 70 reads the collision determination value (hereinafter referred to as the old collision determination value) stored in the EEPROM 40 of the protective device ECU 28,
The old collision determination value is multiplied by the collision correction coefficient K to obtain a new collision determination value (hereinafter referred to as a new collision determination value).

[0053]

[Equation 2]

The old collision determination value stored in the EEPROM 40 is a collision determination value set for a vehicle before the grill guard 24 is retrofitted, that is, a standard vehicle. Therefore, the vehicle after the grill guard 24 is retrofitted (vehicle with grill guard), that is, the rigidity is changed by multiplying the old collision determination value by the collision correction coefficient K obtained by the equation (1). A new collision judgment value to be set for the vehicle is obtained. In this way, when the new collision determination value is determined for the vehicle whose rigidity has been changed, the determined new collision determination value is used as the protective device ECU 2
8 and rewrites the old collision determination value stored in the EEPROM 40 with the new collision determination value. For rewriting the collision determination value in the EEPROM 40, for example, the method described in the above-mentioned JP-A-6-316248 may be used.

As described above, since the collision determination value is changed, the correct activation determination of the occupant protection device is assured even in the vehicle 20 to which the grill guard 24 is attached later.

As described above, according to this embodiment,
Since only the grill guard 24 and the bumper 26 of the vehicle 20 are hit, the body 22 is not deformed and the vehicle 20 is not unusable. Therefore, the vehicle 20 can be reused, and the cost can be reduced. Further, since the working time is short, it is possible to shorten the lead time until the collision determination value is determined. Furthermore, according to the present embodiment, various vehicles can be supported as long as the collision determination value can be changed, and the ECUs can be unified among the vehicles.

In the embodiment shown in FIG. 1, the hammer 42 is provided with the acceleration sensor 44 to measure the impact applied to the hammer 42, but the impact force of the hammer 42 strikes the grill guard vehicle. Even if the hammer 42 is not provided with the acceleration sensor 44, only the value measured by the acceleration sensor 38 of the protective device ECU 28 (that is, the impact applied to the vehicle 20) is provided as long as the case and the standard vehicle are hit. Therefore, it is possible to determine the collision determination value.

In the embodiment shown in FIG. 1, the vehicle 20
The acceleration applied to the hammer and the impact applied to the hammer 42 were measured as the acceleration by the acceleration sensors 38 and 44, but the acceleration is not limited to the acceleration, and the differential value of the acceleration may be measured, or the acceleration is integrated once. The value that is the velocity may be measured, and further, the movement amount that is the twice integrated value of the acceleration may be measured.

In the embodiment shown in FIG. 1, the case where the grill guard 24 is attached as a retrofit component has been described. However, even when a winch or the like is retrofitted, since the rigidity of the vehicle is changed, the grill guard 24 is attached. It is necessary to change the collision judgment value as in the case of. In addition, in addition to the above, a part that influences the rigidity of the vehicle is additionally provided in the path from the portion that may be initially impacted by the vehicle collision to the acceleration sensor 38 (that is, the impact propagation path). Also in this case, it is necessary to change the collision determination value. Therefore, in any of these cases, when the collision determination value is changed, a new collision determination value may be determined by the method described above.

Furthermore, in the embodiment shown in FIG.
In determining a new collision judgment value, first, the formula (1)
As described above, the collision correction coefficient K is obtained by taking the ratio of the integrated value ratio G2 / G1, but the collision correction coefficient K may be obtained by taking the ratio of acceleration or the speed ratio. Further, it is also possible to extract the peak value of the acceleration signal a2 shown in FIG. 4C and determine the collision determination value based on this without extracting the collision correction coefficient K.

Further, in the embodiment shown in FIG. 1, the collision determination value stored in the EEPROM 40 of the protective device ECU 28 (that is, the collision determination value used until then) is newly determined. However, the present invention is not limited to this, and for example,
The following may be performed. RO in the protective device ECU 28
M is provided, and a plurality of values that are candidates for the collision determination value are stored in the ROM. Then, the collision determination value calculation circuit 70
When a new collision determination value is calculated by, for example, a value closest to the calculated collision determination value is selected from the values stored in the ROM, and the new value is used instead of the previously selected value. It is determined as a collision determination value. Alternatively, a new collision determination value is directly determined from the values stored in the ROM based on the acceleration signals a1 and a2, the speed signals v1 and v2, the integrated values G1 and G2, and the like. Is also good.

Next, another embodiment of the present invention will be described. FIG. 6 is a configuration diagram showing a collision determination value determination device as another embodiment of the present invention. In this embodiment, a case will be described in which the collision determination value is changed in response to deterioration in vehicle rigidity due to aging or the like. As shown in FIG. 6, this collision determination value determination device mainly includes a protective device ECU 28 mounted in the central portion of the vehicle 20, a vibration exciter 80 and an acceleration sensor 82 mounted in the bumper 26,
It consists of.

The body 22 of the vehicle 20 is constructed by joining metals such as iron by spot welding or the like, and a bumper 26 is attached to the front portion thereof.

The vibrator 80 is fixed in the bumper 26 and applies a vibration of a predetermined frequency to the bumper 26 portion of the vehicle 20 in response to a drive signal from the protective device ECU 28. A sine wave is used as the vibration waveform at this time, and the vibration frequency includes a margin of 10 to 500 Hz of the acceleration signal detected by the acceleration sensor 38 in the protective device ECU 28 at the time of a vehicle collision. 5 to 800 Hz is used. To add vibration, first add a frequency of 5 Hz and then a frequency of 50 Hz.
In the following, 100 Hz, 150 Hz, and so on are sequentially added up to 800 Hz by time division. The magnitude of the applied vibration is at least such that the vibration propagates in the vehicle 20 through the bumper 26 and the body 22 and reaches the protective device ECU 28.

The acceleration sensor 82 is a sensor for detecting the vibration applied to the bumper 26 portion of the vehicle 20 by the vibration exciter 80 which is a shock applying means. As shown in FIG. 6, the acceleration sensor 82, which is an additional impact measuring means, is installed in the bumper 26 in the vicinity of the vibration exciter 80, independently of the vibration exciter 80. You may make it comprised integrally.

Further, the protective device ECU 28 has substantially the same structure as that shown in FIG. 1, and the acceleration sensor 38, the CPU 36, and the EEP, which are propagation shock measuring means.
Although the ROM 40 is mainly provided, the arrangement of each component is different from that shown in FIG. These components are housed in the case 30, and the case 30 includes the bracket 3
2 supported.

FIG. 7 is a block diagram showing a structural example of the protective device ECU 28 of FIG. As shown in FIG. 7, the protective device ECU 28 includes a CPU 36, an acceleration sensor 38, an EEPROM 40, and a vibrator driving circuit 39. The CPU 36 functions as the collision determination unit 35 and the collision determination value determination unit 37 according to the program.

Similar to the embodiment shown in FIG. 1, the acceleration sensor 38 constantly measures the acceleration applied to the vehicle 20 while the vehicle is running, and the obtained measurement value is processed by a processing circuit (not shown). It is input to the collision determination unit 35 of the CPU 36 via the.
The collision determination unit 35 of the CPU 36 performs arithmetic processing on the input measured value to obtain an arithmetic value, and at the same time, EEPRO
The collision judgment value is read from M40. As the calculated value, for example, a moving average value (that is, an integrated value) for 10 ms or 90 ms is used.

After that, the collision determination section 35 of the CPU 36
The calculated value thus obtained is compared with the read collision determination value, and it is determined whether or not an occupant protection device (not shown) such as an airbag device is to be activated depending on the magnitude relationship. That is, when a vehicle collision occurs, the calculated value exceeds the collision determination value, and accordingly, an activation signal is generated for the occupant protection device to activate the occupant protection device.

Next, the vehicle 20 due to secular change or the like
Consider the case where the collision determination value is changed in response to the deterioration of the rigidity of. In this embodiment, the following method is used to obtain a new collision determination value.

The collision determination value determination processing in this embodiment is as follows.
In order to cope with the deterioration of the rigidity of the vehicle 20 due to aging,
It is performed regularly (for example, every time the vehicle 20 is started) or irregularly (for example, when the user brings the vehicle 20 to a dealer).

8 and 9 are flowcharts showing the flow of the collision determination value determination processing by the CPU 36 of FIG.
As shown in FIG. 8, when the collision determination value determination process is started, first, the collision determination value determination unit 37 of the CPU 36 controls the shaker drive circuit 39 to drive the shaker 80, Vibration of a predetermined frequency n is applied to the bumper 26 portion of the vehicle 20 (step S20). Frequency n of vibration applied at this time
Is 5 Hz as described above.

When vibration is applied to the bumper 26 portion by the vibration exciter 80, the vibration is a mechanical shock (ie, shock force or shock wave), and the bumper 26 shown in FIG.
It propagates through the body 22 in order, and further, ECU for protection devices
The acceleration sensor 38 reaches the acceleration sensor 38 through the bracket 32 of 28 and the case 30, and is measured as acceleration by the acceleration sensor 38. The measurement result is input to the collision determination value determination unit 37 of the CPU 36 as an acceleration signal b2 as shown in FIG.

At the same time, the acceleration sensor 82 in the bumper 26 measures the vibration applied to the bumper 26 portion by the vibrator 80 as acceleration. As a result of the measurement, as shown in FIG.
It is input to the collision determination value determination unit 37 of 36.

Next, the collision determination value determination unit 37 of the CPU 36
Is the input acceleration signal b1 from the acceleration sensor 82.
And the acceleration signal b2 from the acceleration sensor 38 is read (steps S22 and S24), and the attenuation degree Dnew of the acceleration signal is calculated based on the read acceleration signals b1 and b2 (step S26). The attenuation degree D of the acceleration signal can be obtained according to the equation (3).

[0076]

(Equation 3)

That is, the damping degree D is attenuated while the vibration (that is, the shock) applied to the bumper 26 portion of the vehicle 20 by the vibration exciter 80 is attenuated while propagating in the vehicle 20, so that the ECU 28 for the protection device 28 is protected. It shows how much the signal was attenuated before reaching the acceleration sensor 38.

Incidentally, the EEPROM 40 stores the previously determined collision determination value (that is, the old collision determination value), but in addition to this, it is calculated in the same manner as above when determining the previous collision determination value. The attenuated attenuation Dold is stored. The damping degree Dold is calculated and stored for each frequency n of the vibration generated by the vibration exciter 80.

Therefore, next, the collision determination value determining unit 37 of the CPU 36 selects from the EEPROM 40 the vibration exciter 80 out of the damping degree Dold obtained in the previous determination of the collision determination value.
The attenuation degree Dold corresponding to the frequency n (in this case, n = 5 Hz) of the generated vibration is read (step S28). Then, the collision correction coefficient Ln is calculated based on the damping degree Dnew obtained in step S26 (that is, the damping degree obtained when the collision determination value is determined this time) and the damping degree Dold read in step S28 for the frequency n of vibration. Calculate (step S30). The collision correction coefficient Ln for the frequency n can be obtained according to the equation (4).

[0080]

(Equation 4)

As described above, the damping degree D is
Since it represents how much the vibration applied by the vehicle 20 is attenuated during the propagation in the vehicle 20, when the rigidity of the vehicle 20 is deteriorated or changed, the value of the attenuation degree D naturally changes. To do. Therefore, if the rigidity of the vehicle 20 has deteriorated due to secular change or a slight collision accident between the time when the previous collision determination value is determined and the time when the current collision determination value is determined, this time, Since the newly obtained damping degree Dnew has a different value compared to the previously obtained damping degree Dold, the collision correction coefficient Ln is such that the newly obtained damping degree Dnew is different from the previously obtained damping degree Dold. The degree of change due to the deterioration of the rigidity of the vehicle 20. That is, in other words, the collision correction coefficient Ln represents how much the rigidity of the vehicle 20 deteriorates between the time when the previous collision determination value is determined and the time when the current collision determination value is determined. I can say.

Next, the collision determination value determination unit 37 of the CPU 36
Is the frequency n of the vibration generated by the shaker 80 is 800 Hz
Is determined ((step S32), it is still 80
If it is not 0 Hz, the frequency n of the vibration to be generated by the vibration exciter 80 is changed to the next frequency value (for example,
If n = 5 Hz, change to n = 50 Hz).
Then, the process returns to step S20 again, and the same process is repeated for the next frequency.

When it is determined in step S32 that the frequency n of the vibration generated by the vibration exciter 80 is 800 Hz, the process proceeds to step S36 in FIG.
The average value L of the collision correction coefficients Ln calculated for each frequency is calculated. As a result, even if the calculated collision correction coefficient Ln varies for each frequency n, it is possible to obtain an averaged collision correction coefficient.

Subsequently, the collision determination value determination unit 3 of the CPU 36
7 reads the old collision determination value (that is, the previously determined collision determination value) stored in the EEPROM 40 of the protective device ECU 28 (step S38), and the average value L of the collision correction coefficient Ln is used as the old collision determination value. Multiplication is performed to obtain a new collision determination value (step S40).

That is, as described above, the collision correction coefficient is
It can be said that it represents the degree of rigidity deterioration of the vehicle 20 between the time when the previous collision determination value is determined and the time when the current collision determination value is determined. Therefore, the average value L of this collision correction coefficient is used as the old collision. By multiplying the determination value, the vehicle 20
It is possible to obtain a new collision determination value corresponding to the deterioration of the rigidity of. That is, when the average value L of the collision correction coefficient is greater than 1, the collision determination value is increased, and conversely, 1
If it is smaller, the collision determination value is reduced.

When the new collision judgment value is obtained in this way, the CPU
The collision determination value determination unit 37 of 36 writes the obtained new collision determination value in the EEPROM 40, and the EEPROM 40
It is rewritten with the old collision determination value stored in. And
Furthermore, the attenuation degree Dnew calculated in step S26 described above.
Also, each frequency n is written in the EEPROM 40 and rewritten with the previous attenuation degree Dold stored in the EEPROM 40 (step S42).

As described above, by performing the collision determination value determination process regularly or irregularly, even if the rigidity of the vehicle is deteriorated due to secular change due to long-term use or a slight collision accident, it is possible to cope with it. As described above, an appropriate collision determination value can be determined, so that an accurate activation determination for the occupant protection device is guaranteed.

As described above, according to this embodiment,
Since the vibrator 80 only applies vibration to the bumper 26 portion of the vehicle 20, the body 22 is not deformed and the vehicle 20 is not unusable. Therefore, the vehicle 20 can be reused, and the cost can be reduced. Further, since the working time is short, it is possible to shorten the lead time until the collision determination value is determined. Furthermore, according to the present embodiment,
As long as the collision judgment value can be changed, various vehicles can be supported, and the ECUs of the vehicles can be unified. Further, when the acceleration sensor 38 is of a semiconductor type, the self-diagnosis of the acceleration sensor 38 is normally performed only by the continuity check. However, according to the present embodiment, the vehicle is actually vibrated and its vibration is detected. Since it can be actually detected by the acceleration sensor 38, more reliable self-diagnosis can be performed by using this function.

By the way, in the embodiment shown in FIG. 6, the frequency of 5 Hz, 50 Hz, 1
00 Hz, 150 Hz, ..., 800 Hz, etc., a plurality of frequencies are sequentially added in a time division manner, a collision correction coefficient Ln is calculated for each frequency n, and an average value L thereof is calculated,
The average value L is used to determine the new collision determination value. However, the present invention is not limited to this, and by using the vibration exciter 80, for example, by adding only a single specific frequency such as a frequency of 300 Hz, the collision correction coefficient for the specific frequency is obtained. hand,
The new collision determination value may be determined using the collision correction coefficient.

As described above, instead of adding a plurality of discrete frequencies in a time division manner, continuous frequencies may be added at once. That is, the protective device ECU
A frequency analysis circuit (FFT) is newly provided in 28, a vibration having a continuous frequency of, for example, 5 Hz to 800 Hz is applied by the vibration exciter 80, and the added vibration is detected by the acceleration sensors 38 and 82, respectively. Each of the obtained acceleration signals is input to a frequency analysis circuit, and the frequency analysis circuit obtains signal levels of a plurality of desired frequencies for each acceleration signal. After that, the collision correction coefficient is calculated for each frequency and the new collision determination value is determined by using the average value thereof, in the same manner as in the case of adding a plurality of frequencies in a time division manner as described above.

In the embodiment shown in FIG. 6, the vehicle 20
Although the vibration (i.e., impact) applied to the bumper 26 portion or the vibration propagating in the vehicle 20 was measured as acceleration by the acceleration sensors 38 and 82, the acceleration is not limited to acceleration, and a differential value of acceleration is measured. Alternatively, the velocity, which is the once-integrated value of acceleration, may be measured, or the movement amount, which is the twice-integrated value of acceleration, may be measured.

Further, in the embodiment shown in FIG. 6, the old collision judgment value stored in the EEPROM 40 in the protective device ECU 28 is rewritten to the new collision judgment value, but the present invention is not limited to this. Not something, for example,
As described in the embodiment shown in FIG. 1, a ROM is provided in the protection device ECU 28, and a plurality of values that are candidates for the collision determination value are stored in the ROM, and a new calculated value is stored in the ROM. A value that is closest to the collision determination value may be selected, and a new collision determination value may be determined instead of the value that was previously selected.

The present invention is not limited to the above-described examples and embodiments, but can be carried out in various modes without departing from the scope of the invention.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a collision determination value determination device as one embodiment of the present invention.

FIG. 2 is an enlarged view showing a protection device ECU 28 of FIG. 1 in an enlarged manner.

3 is a block diagram showing a configuration of an arithmetic processing unit 46 of FIG.

FIG. 4 is a diagram showing acceleration signals a1 and a2 and velocity signal v in FIG.
It is a characteristic view which shows an example of the time change of 1 and v2.

FIG. 5 is an explanatory diagram showing a magnitude relationship of integral values G1, G2 and integral value ratio G1 / G2 obtained for a standard vehicle and a vehicle with a grill guard.

FIG. 6 is a configuration diagram showing a collision determination value determination device as another embodiment of the present invention.

7 is a block diagram showing a configuration example of the protective device ECU 28 of FIG.

8 is a flowchart showing a flow of a collision determination value determination process by the CPU 36 of FIG.

9 is a flowchart showing the flow of a collision determination value determination process by the CPU 36 of FIG.

[Explanation of symbols]

 20 ... Vehicle 22 ... Body 24 ... Grill guard 26 ... Bumper 28 ... Protective device ECU 30 ... Case 32 ... Bracket 34 ... Printed circuit board 35 ... Collision determination part 36 ... CPU 37 ... Collision determination value determination part 38 ... Acceleration sensor 39 ... Exciter drive circuit 40 ... EEPROM 42 ... Hammer 44 ... Acceleration sensor 46 ... Arithmetic processing device 50,52 ... Amplifier 54,56 ... Filter 58,60 ... Integration circuit 62,64 ... Calculation circuit 66 ... Integral value ratio calculation circuit 68 ... Correction coefficient calculation circuit 70 ... Collision determination value calculation circuit 80 ... Exciter 82 ... Acceleration sensor Dnew, Dold ... Damping degree K ... Collision correction coefficient Ln ... Collision correction coefficient a1, a2 ... Acceleration signal b1, b2 ... Acceleration signal v1 , V2 ... Velocity signal G1, G2 ... Integral value G1 / G2 ... Integral value ratio

Claims (10)

[Claims] 1. A collision determination value determination device for determining a collision determination value used to determine whether or not to activate an occupant protection device in a vehicle at the time of a vehicle collision, wherein the collision determination value determination device is provided in a specific portion of the vehicle. An impact adding means for applying an impact to the extent that does not deform the vehicle, and the impact applied to the vehicle and propagating in the vehicle,
Propagation impact measuring means for measuring at a position different from the specific portion in the vehicle, and collision determination value determining means for determining the collision determination value based on the measurement value obtained by the propagation impact measuring means. Collision judgment value determination device. 2. The collision determination value determination device according to claim 1, wherein the impact adding means includes a striking means that strikes the specific portion of the vehicle and applies the impact to the specific portion. Decision device. 3. The collision determination value determination device according to claim 1, wherein the impact adding means applies a predetermined vibration to the specific portion of the vehicle to apply the impact to the specific portion. A collision determination value determination device provided. 4. The collision determination value determination device according to claim 1, 2 or 3, wherein the impact adding means is mounted on the vehicle. 5. The collision determination value determination device according to any one of claims 1 to 4, wherein an additional impact measurement for measuring the impact applied to the specific portion of the vehicle by the impact applying means. With further means, the collision determination value determining means determines the collision determination value based on the measurement value obtained by the propagation impact measurement means and the measurement value obtained by the additional impact measurement means. A collision determination value determination device characterized by: 6. The collision determination value determination device according to any one of claims 1 to 5, wherein the specific portion of the vehicle is a retrofit component portion retrofitted to the vehicle. Collision judgment value determining device. 7. The collision determination value determination device according to any one of claims 1 to 6, wherein the collision determination value determination means is mounted in the vehicle and stores a plurality of values. A collision determination value determination device comprising: and a selection unit that selects a desired value from the plurality of values stored in the storage unit based on the measured value and determines the selected value as the collision determination value. . 8. The collision determination value determination device according to any one of claims 1 to 7, wherein in the vehicle when the collision determination value is newly determined by the collision determination value determination means. The collision determination value determination device further comprising a replacement unit that replaces the used collision determination value with the newly determined collision determination value. 9. A collision determination value determination method for determining a collision determination value used to determine whether or not an occupant protection device in a vehicle is activated at the time of a vehicle collision, comprising: (a) identifying the vehicle. A step of applying an impact to a portion that does not deform the vehicle; (b) a step of measuring the impact applied to the vehicle and propagating in the vehicle; and (c) a step obtained in the step (b). Determining the collision determination value based on the measured value obtained. 10. A collision determination value determination method for determining a collision determination value used to determine whether or not to activate an occupant protection device in a vehicle at the time of a vehicle collision, comprising: (a) identifying the vehicle. Applying a shock to a portion of the vehicle such that the vehicle is not deformed; (b) measuring the shock applied to the specific part of the vehicle; and (c) applying the shock to the vehicle inside the vehicle. A step of measuring the impact propagating through the vehicle, and (d) a step of determining the collision determination value based on the measurement value obtained in the step (b) and the measurement value obtained in the step (c). A method for determining a collision determination value, comprising: