JP2001278000A - Vehicle collision determination device - Google Patents

Abstract

(57) [Problem] To perform an appropriate collision determination in a short time according to the severity of a collision with a simple and inexpensive configuration. SOLUTION: A collision determination unit 12 generates a start signal of an airbag device based on an acceleration signal G of an acceleration sensor 11. The occupant movement amount calculation unit 21 of the severe collision detection unit 13 calculates the occupant movement amount S by integrating the acceleration signal G twice.
The offset processing unit 24 determines that the occupant movement amount S is equal to the threshold movement amount S _TH
When: calculates the offset acceleration G _Off exceeding the offset value G _O from the acceleration signal G. The speed change calculator 25 calculates a speed change ΔV _Off by integrating the offset acceleration G _Off with time. The elapsed time calculation unit 27 determines that the speed change ΔV _Off is equal to the first and second threshold speed changes ΔV _TH1 , ΔV
_The elapsed time ΔT existing between _TH2 is calculated, and it is determined whether or not it is smaller than the threshold elapsed time ΔT _TH . The airbag is rapidly deployed or slowly deployed according to the determination result.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle collision judging device for judging a collision of a vehicle and activating an occupant protection device such as an air bag device, and more particularly to a vehicle collision judging device according to the magnitude of an impact at the time of a collision. The present invention relates to a technique for controlling the operation of an occupant protection device.

[0002]

2. Description of the Related Art Conventionally, an acceleration sensor for detecting, for example, acceleration (or deceleration) applied to a vehicle is provided, and a change in vehicle acceleration is detected by an acceleration signal output from the acceleration sensor. 1
When the integrated values exceed the predetermined threshold values after the integration is performed twice or twice, a vehicle collision determination device that activates an occupant protection device such as an airbag device or a seatbelt pretensioner is known. Have been. When a collision is determined by such a vehicle collision determination device, for example, the airbag device ignites the gas generating agent by a squib in the inflator to generate gas from the inflator,
The gas inflates the airbag to suppress the secondary collision between the occupant and the interior components.

[0003]

In the vehicle collision determining apparatus according to one example of the prior art, the detected acceleration signal is independent of the magnitude of the impact at the time of the collision and the position of the occupant in the vehicle. There is a case where the airbag is set to deploy with a certain characteristic only when the calculated value exceeds a predetermined threshold, and even if there is a difference in the collision situation, there is a problem that only the same control can be performed. is there. The present invention has been made in view of the above circumstances, and by using the acceleration at the initial stage of a collision, it is possible to perform a proper collision determination in a short time with a simple and inexpensive configuration according to the severity of the collision. It is an object to provide a vehicle collision determination device.

[0004]

According to the present invention, there is provided a method for solving the above problems.
A vehicle according to the invention as claimed in claim 1 to achieve the object.
Collision determination device for detecting acceleration acting on the vehicle.
Speed detecting means (for example, acceleration in an embodiment described later)
Sensor 11) and the acceleration detected by the acceleration detecting means.
Velocity signal (for example, acceleration signal in the embodiment described later)
G), a predetermined offset value (for example, an implementation
Value G in the form of_OOffset acceleration exceeding
Degree (for example, the offset acceleration in the embodiment described later)
G_Off) (For example, described later)
The offset processing unit 24) in the preferred embodiment,
The offset acceleration calculated by the offset processing means
Is integrated over time to change the speed (for example,
Speed change ΔV in the embodiment _Off) To calculate the speed change
Output means (for example, speed change calculation in the embodiment described later)
Unit 25), and the time change with respect to the speed change is a predetermined threshold
Value (for example, threshold speed change ΔV in the embodiment described later)
_TH3) Severe collision determination means for determining whether or not
For example, first and second speed change determinations in an embodiment described later
Units 26a and 26b, elapsed time calculation unit 27, and elapsed time
Determination unit 28) and a determination result by the severe collision determination unit.
The occupant protection device (for example, an embodiment described later)
Control signal to control the operation of the airbag device)
Control signal generating means (for example, in an embodiment described later)
Collision signal generator 29 and non-severe collision signal generation
30).

[0005] According to the vehicle collision determination device having the above structure,
During a short time at the time of the collision, the magnitude of the impact at the time of the collision is detected by utilizing the acceleration different according to the vehicle speed, that is, the difference in the repulsion deceleration of the vehicle body, and according to the magnitude of the impact, For example, it is possible to appropriately control the activation timing and operation of an occupant protection device such as an airbag device and a seatbelt pretensioner, for example, the operation of deploying an airbag. For example, FIGS. 1A to 1C are graphs showing a time change of an acceleration signal G (positive in the deceleration direction) in a frontal collision with different vehicle speeds, and FIG.
It is a graph which shows the speed change based on the acceleration signal _Goff after offset processing with respect to (a)-(c). Here, FIG. 1A shows a collision at a high speed (for example, about 50 km / h), FIG. 1B shows a collision at a medium speed (for example, about 20 km / h), and FIG. For example, about 12 km / h)
When a predetermined offset value G _O is set for the acceleration signal G, the offset acceleration G _Off exceeds the offset value G _O as the vehicle speed at the time of the collision increases.
The offset acceleration G _Off exceeding the offset value G _O decreases as the vehicle speed decreases.

[0006] Here, according to the following equation (1), by integrating with the offset acceleration G _Off exceeding the offset value G _O time, to calculate the velocity change [Delta] V _Off. However, FIG.
As shown in (c), the acceleration signal G is the offset value _Go.
, The offset acceleration G _Off and the speed change ΔV _Off become zero.

[0007]

(Equation 1)

That is, the offset acceleration G _Off is integrated once with respect to time to obtain a predetermined time interval (for example, 0 ≦ t).
The speed change ΔV _off at ≦ n) is calculated. The speed change [Delta] V _{o ff,} for example, as shown in FIG. 2, shows a large change in velocity as the vehicle speed at the time of collision is a high speed, on the contrary, shows a small change in speed as slow. Here, the speed change Δ
For example, two threshold speed changes ΔV _TH1 and ΔV with respect to V _{off
TH 2} (ΔV _TH1 ≦ ΔV _TH2 ) is set, and the speed change Δ
The elapsed time ΔT until V _off exceeds one threshold speed change ΔV _TH1 and reaches the other threshold speed change ΔV _TH2 is measured. Then, the elapsed time ΔT becomes shorter as the collision speed increases,
For example, as shown in FIG. 2, the elapsed time ΔT1 in a high-speed collision (solid line a in FIG. 2) is equal to the medium-speed collision (FIG.
Is shorter than the elapsed time ΔT2 in the solid line b) shown in FIG.

Therefore, at least one or more (for example, one) threshold elapsed time ΔT _TH is set for the elapsed time ΔT, and the elapsed time ΔT is compared with the threshold elapsed time ΔT _TH , so that the collision time ΔT _TH can be determined. Of the impact, that is, the intensity of the impact can be determined. For example, the elapsed time ΔT is equal to the threshold elapsed time ΔT _TH
If it is below, it is determined that the collision is at a high speed, that is, a severe collision. For example, one threshold speed change ΔV _TH3 is set for the speed change ΔV _off , and the speed change ΔV _off is set.
When V _off exceeds the threshold speed change ΔV _TH3 , it may be determined that the collision is at a high speed, that is, a severe collision. If it is determined that the collision is severe, for example, the airbag is rapidly deployed to give priority to protecting the occupant. Conversely, when it is determined that the collision is not severe, the airbag is slowly deployed by, for example, deploying the airbag in multiple stages. Thereby, the occupant protection device such as the airbag device can be appropriately controlled according to the situation of the collision.

Further, in the vehicle collision judging device according to the present invention, the severe collision judging means may determine that the speed change has two threshold speed changes (for example, a first threshold value in an embodiment described later). Speed change ΔV _TH1 , second threshold speed change Δ
Elapsed time detecting means (for example, an elapsed time calculation unit 2 in an embodiment described later) that detects an elapsed time (e.g., an elapsed time ΔT in an embodiment described below) positioned between V _TH2 ).
7) and an elapsed time determination unit (for example, an elapsed time determination in an embodiment described later) that determines whether the elapsed time is equal to or less than a threshold time (for example, a threshold elapsed time ΔT _{TH in} an embodiment described below). (28).

According to the vehicle collision determination device having the above configuration,
If the elapsed time at which the speed change is located between two different threshold speed changes is equal to or less than the threshold time, the time change of the speed change is small, and it can be determined that the collision is severe, and conversely, the elapsed time is the threshold time. If it is larger, the time change of the speed change is relatively large, and it can be determined that the collision is not severe.

Further, the vehicle according to the third aspect of the present invention.
The collision judging device moves the occupant based on the acceleration signal.
Amount (for example, the occupant movement amount S in the embodiment described later)
Moving amount calculating means for calculating (for example, an embodiment described later)
The occupant movement amount calculation unit 21) determines that the occupant movement amount is
Movement amount (for example, threshold movement amount in the embodiment described later)
S _TH) The movement amount determination means (for example,
The occupant movement amount determination unit 22) in the embodiment described later,
The speed change according to the determination result by the moving amount determination means.
Control means for controlling the operation of the calculation means (for example,
Offset processing control unit 23) in the embodiment,
The control means may control whether the movement amount is equal to or greater than the threshold movement amount.
Wherein the calculation of the speed change is stopped.
I have.

According to the vehicle collision determination device having the above configuration,
If the movement amount of the occupant is smaller than the threshold movement amount, a speed change is calculated based on the acceleration signal, and based on the speed change, the magnitude of the impact at the time of the collision, that is, whether the collision is severe or not. Is performed. Then, when it is determined that the collision is severe, for example, the airbag is rapidly deployed to protect the occupant. On the other hand, when the movement amount of the occupant is equal to or larger than the threshold movement amount, the determination process of whether or not the collision is severe is not performed, and regardless of the magnitude of the impact at the time of the collision, for example, the airbag has a constant characteristic. To slowly deploy. Thus, the occupant protection device such as the airbag device can be appropriately operated according to the amount of movement of the occupant in the vehicle in addition to the magnitude of the impact at the time of the collision.

Further, according to a fourth aspect of the present invention, there is provided a vehicle collision judging device comprising a collision judging means (for example, a collision judging unit 12 in an embodiment described later) for detecting a collision based on the acceleration signal. The control signal generation means is characterized in that the control signal generation means generates the control signal based on a result of the determination by the severe collision determination means and detection of a collision by the collision determination means.

According to the vehicle collision determination device having the above configuration,
For example, if the collision is determined by the collision determination unit, the airbag is set to be slowly deployed, and further, the collision is determined by the collision determination unit, and the severe collision is determined by the severe collision determination unit. If it is determined, by setting to deploy the airbag rapidly,
An occupant protection device such as an airbag device can be appropriately controlled according to the state of the collision. In addition, when a severe collision is determined, the determination is made based on two determination results, that is, the determination result of the collision determination unit and the determination result of the severe collision determination unit, so that the determination is made more reliably. Processing can be performed.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a vehicle collision judging device according to an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 3 is a configuration diagram of the vehicle collision determination device 10 according to one embodiment of the present invention. The vehicle collision determination device 10 according to the present embodiment includes an acceleration sensor (G sensor) 11,
It is provided with a collision determination unit 12 and a severe collision detection unit 13. The collision determination unit 12 includes, for example, a filter processing unit including, for example, a low-pass filter that removes a high-frequency component that is a noise component from the acceleration signal G output from the acceleration sensor 11, and an acceleration signal G after filtering.
And an A / D converter for converting the digitalized acceleration signal G into a digital signal once with respect to time.
Alternatively, there is provided a determination unit that performs integration twice and determines that a collision has occurred when these integrated values exceed predetermined threshold values.

The severe collision detection unit 13 includes an occupant movement amount calculation unit 21, an occupant movement amount determination unit 22, an offset processing control unit 23, an offset processing unit 24, a speed change calculation unit 25, and a first It is provided with a speed change determination unit 26a, a second speed change determination unit 26b, an elapsed time calculation unit 27, an elapsed time determination unit 28, and a severe collision signal generation unit 29. The occupant movement amount calculating unit 21 calculates the occupant movement amount S in the vehicle by integrating the acceleration signal G output from the acceleration sensor 11 twice with respect to time. Occupant moving amount determining section 22 determines whether or not the occupant movement amount S calculated by the occupant moving amount calculating unit 21 is larger than the threshold amount of movement S _TH, and outputs a command signal based on the determination result .

The offset processing control unit 23 determines, for example, the occupant movement amount S
Is larger than the threshold movement amount S _TH , the operation of the offset processing unit 24 described later is stopped. That is, the offset processing control unit 23 includes, for example, a switch or the like, and interrupts the input of the acceleration signal G to the offset processing unit 24 according to the determination result of the occupant movement amount determination unit 22. Offset processing unit 24, for a given offset value G _O set for the acceleration signals G, calculates the offset acceleration G _Off exceeding the offset value G _O. Here, when the acceleration signal G is smaller than the offset value G _O is
The offset acceleration G _{Off is set} to zero. The speed change calculator 25 calculates the speed change ΔV _Off by the above equation (1) based on the offset acceleration G _Off .

The first speed change determining unit 26a determines whether the speed change ΔV _Off calculated by the speed change calculating unit 25 is greater than a predetermined first threshold speed change ΔV _TH1 .
For example, the speed change ΔV _Off is equal to a predetermined first threshold speed change ΔV.
Outputs the time x exceeding _TH1 . Second speed change determination unit 2
6b is the speed change Δ calculated by the speed change calculator 25.
It is determined whether V _Off is greater than a predetermined second threshold speed change ΔV _TH2 , and for example, a time y at which the speed change ΔV _Off exceeds the predetermined second threshold speed change ΔV _TH2 is output. It should be noted that, for the first and second threshold speed changes ΔV _TH1 and ΔV _TH2 , for example, ΔV _TH1 <ΔV _TH2 .

Based on the times x and y output from the first and second speed change determination units 26a and 26b, the elapsed time calculation unit 27 calculates the speed change ΔV _Off as a first threshold speed change ΔV _TH1 and a second threshold speed change ΔV _TH1 . Elapsed time ΔT existing between speed change ΔV _TH2
(ΔT = y−x) is calculated. The elapsed time determination unit 28
It determines whether or not the elapsed time ΔT calculated by the elapsed time calculator 27 is equal to or less than the threshold elapsed time ΔT _TH, and outputs a command signal based on the determination result.

The severe collision signal generating section 29 determines whether or not the impact of the generated collision is large, and outputs, for example, a command for rapidly deploying the airbag. For this reason,
The severe collision signal generation unit 29 receives a signal from the collision determination unit 12
An activation signal indicating that a collision that needs to activate an occupant protection device such as an airbag device has occurred, and a severe collision determination signal indicating that a severe collision has occurred is input from the severe collision detection unit 13. And the AND of both signals
When the condition is satisfied, for example, a simultaneous ignition command for rapidly deploying the airbag is output. On the other hand, AND of both signals
The NOT signal for the condition and the activation signal from the collision determination unit 12 are input to the non-severe collision signal generation unit 30, and the AND condition of the two signals, that is, the need to activate the occupant protection device such as the airbag device. A collision occurred,
When it is determined that the collision is not a severe collision, a multi-stage (for example, two-stage) ignition command for slowly expanding the air bag is output, for example. In addition, the multi-stage ignition command is not to generate gas at the maximum output at once when generating gas from the inflator and deploying the air bag, for example, to sequentially ignite a plurality of gas generating agents in a stepwise manner. It generates gas.

Vehicle collision determining apparatus 1 according to this embodiment
0 has the above-described configuration. Next, the operation of the vehicle collision determination device 10, in particular, the processing in which the severe collision detection unit 13 determines whether or not the generated collision is a severe collision is described with reference to FIG. This will be described with reference to FIG. FIG. 4 is a flowchart showing the operation of the vehicle collision determination device 10. First, in step S1 shown in FIG.
1 to read the acceleration signal G detected. Next, in step S2, the acceleration signal G is sent to the occupant movement amount calculation unit 21, and the occupant movement amount S is calculated by integrating twice over time to determine whether the occupant movement amount S is equal to or greater than the threshold movement amount S _TH . Determine whether or not. If the result of this determination is "YES",
Proceeding to step S8, a series of processing ends.

On the other hand, if the determination result is "NO", the operation proceeds to step S3, and transmits the acceleration signal G in the offset processing unit 24 through the offset processing control unit 23, exceeds a predetermined offset value G _O The offset acceleration G _off is calculated. Next, in step S4, the above equation (1)
To calculate the speed change ΔV _off . Next, in step S5, the inclination with respect to time change of the speed change [Delta] V _off, i.e. the speed change [Delta] V _off first threshold speed change of a predetermined Δ
Calculating the elapsed time ΔT when changing from V _TH1 to the second threshold speed change [Delta] V _{TH 2.} Next, in step S6, the slope of the calculated speed change ΔV _off with respect to the time change is
It is determined whether or not it is equal to or more than a predetermined threshold. That is, it is determined whether or not the elapsed time ΔT when the speed change ΔV _off changes from the predetermined first threshold speed change ΔV _TH1 to the second threshold speed change ΔV _TH2 is equal to or less than the threshold elapsed time ΔT _TH . If the result of this determination is "NO", the operation proceeds to step S8, and a series of processing ends. On the other hand, if the result of the determination is "YES", the flow proceeds to step S7, in which it is determined that a severe collision has occurred, for example, a command for rapidly deploying the airbag is output, and the flow proceeds to step S8. A series of processing ends.

That is, when it is determined that the occupant protection device such as the air bag device needs to be activated, the occupant movement amount S is smaller than the threshold movement amount S _TH and the speed change ΔV _off.
If the elapsed time ΔT is less than or equal to the threshold elapsed time ΔT _TH , it is determined that the collision is severe and, for example, the airbag is rapidly deployed. On the other hand, the occupant moving amount S threshold amount of movement S _TH or more, or when the elapsed time [Delta] T for the speed change [Delta] V _off is greater than the threshold time elapsed [Delta] T _TH is, for example, to slow deploy the air back in multiple stages.

As described above, according to the vehicle collision judging device 10 according to the present embodiment, when the collision judging unit 12 judges that a collision has occurred and the activation of the airbag device is instructed, the severe collision detecting unit 13 Since the deployment operation of the airbag is controlled in accordance with the determination result in the above, it is possible to appropriately deploy the airbag in accordance with the collision situation. In this case, the speed change based on the offset acceleration G _Off [Delta] V _Off
, It is possible to remove a small impact component such as a collision at a low speed, and to clearly distinguish a noise signal having a high frequency component such as a bottoming out of a vehicle from an acceleration signal G. can do.

In addition to the magnitude of the impact at the time of the collision,
Since the operation of deploying the airbag is controlled in accordance with the amount of movement of the occupant in the vehicle, the airbag can be more appropriately deployed. Further, the amount of movement of the occupant in the vehicle can be calculated based on the acceleration signal G. For example, there is no need for a camera for monitoring the inside of the vehicle or an appropriate sensor for detecting the position of the occupant on a seat, for example. The vehicle collision determination device 10 can be configured at low cost.

In this embodiment, the speed change Δ
Although one threshold elapsed time ΔT _TH is set for the elapsed time ΔT when V changes from a predetermined first threshold speed change ΔV _TH1 to a second threshold speed change ΔV _TH2 , the present invention is not limited to this.
A plurality of threshold elapsed times ΔT _TH1 ,..., ΔT _THm (m is an arbitrary natural number) may be set. In this case, the magnitude of the impact at the time of collision can be classified in more detail, and the airbag can be deployed in, for example, three or more stages according to the magnitude of the impact.

Further, in the present embodiment, the first and second threshold speed changes ΔV _TH1 , ΔV _{off with} respect to the speed change ΔV _off .
Although V _TH2 is set, it is not limited to this. For example, one threshold speed change ΔV _TH3 is set, and the speed change Δ
When V _off exceeds the threshold speed change ΔV _TH3 , it may be determined that the collision is severe. In this case, the second speed change determination unit 26b, the elapsed time calculation unit 27, and the elapsed time determination unit 28
Can be omitted, and the configuration of the apparatus can be simplified, which can contribute to a reduction in manufacturing costs.

[0029]

As described above, according to the vehicle collision judging device of the first aspect of the present invention, during a short time at the time of a collision, different accelerations depending on the vehicle speed, that is, rebound of the vehicle body. Using the difference in deceleration, the magnitude of the impact at the time of the collision is detected, and according to the magnitude of the impact, the activation timing and operation of an occupant protection device such as an airbag device or a seatbelt pretensioner are determined. It can be controlled appropriately. Moreover, since the speed change is calculated based on the offset acceleration, a small impact component such as a collision at a low speed can be removed in accordance with the offset value with respect to the acceleration signal. Thus, a noise signal having a high frequency component and an acceleration signal can be clearly distinguished. Furthermore, according to the vehicle collision determination device of the present invention, when determining the time change of the speed change, the speed change is determined by the elapsed time located between two different threshold speed changes. Is detected and compared with the threshold time, the determination can be made in a shorter time as the collision becomes more severe. Further, according to the vehicle collision judging device of the present invention, an occupant protection device such as an air bag device in accordance with an occupant movement amount in the vehicle in addition to the magnitude of the impact at the time of the collision. Can be operated properly.
Furthermore, according to the vehicle collision determination device of the present invention, it is possible to more appropriately control the occupant protection device such as the airbag device according to the state of the collision.

[Brief description of the drawings]

FIG. 1 is a graph showing a time change of an acceleration signal G in a frontal collision with different vehicle speeds according to an embodiment of the present invention.

FIG. 2 shows a speed change ΔV with respect to FIGS. 1 (a) and 1 (b).
It is a graph which shows time change of _off .

FIG. 3 is a configuration diagram of a vehicle collision determination device according to an embodiment of the present invention.

4 is a flowchart showing the operation of the vehicle collision determination device shown in FIG.

[Description of Signs] 10 Collision determination device for vehicle 11 Acceleration sensor (acceleration detection means) 12 Collision determination section (collision determination means) 21 Occupant movement amount calculation section (movement amount calculation means) 22 Occupant movement amount determination section (movement amount determination) Means) 23 Offset processing control unit (control unit) 24 Offset processing unit (offset processing unit) 25 Difference calculation unit (Difference calculation unit) 26a First speed change determination unit (Severe collision determination unit) 26b Second speed change determination unit ( Severe collision determination unit) 27 Elapsed time calculation unit (elapsed time detection unit, severe collision determination unit) 28 Elapsed time determination unit (elapsed time determination unit, severe collision determination unit) 29 Severe collision signal generation unit (control signal generation unit) 30 Non-severe collision signal generator (control signal generator)

Claims (4)

[Claims] 1. An acceleration detecting means for detecting an acceleration acting on a vehicle; an offset processing means for calculating an offset acceleration exceeding a predetermined offset value among acceleration signals detected by the acceleration detecting means; Speed change calculating means for calculating a speed change by integrating the offset acceleration calculated by the means with respect to time; severe collision determining means for determining whether a time change with respect to the speed change is equal to or less than a predetermined threshold value; And a control signal generating means for generating a control signal for controlling an operation of the occupant protection device in accordance with a result of the determination by the severe collision determining means. 2. The severe collision determining means, wherein: an elapsed time detecting means for detecting an elapsed time in which the speed change is located between two threshold speed changes; and a determination as to whether the elapsed time is equal to or less than a threshold time. The vehicle collision determination device according to claim 1, further comprising an elapsed time determination unit. 3. A moving amount calculating unit for calculating a moving amount of an occupant based on the acceleration signal; a moving amount determining unit for determining whether the moving amount of the occupant is equal to or more than a threshold moving amount; Control means for controlling the operation of the offset processing means in accordance with the determination result by the means, wherein the control means stops the calculation of the offset acceleration when the movement amount is equal to or greater than the threshold movement amount. The vehicle collision determination device according to claim 1 or 2, wherein: 4. A control device, comprising: a collision determination unit configured to detect a collision based on the acceleration signal; wherein the control signal generation unit performs the control based on a determination result by the severe collision determination unit and a collision detection by the collision determination unit. The vehicle collision judging device according to any one of claims 1 to 3, wherein the signal is generated.