JP2013154838A - Occupant protection control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an occupant protection control device that can improve responsiveness of operation of an occupant protection device to the collision other than a head-on collision such as an oblique collision and offset collision without increasing the number of acceleration sensors.SOLUTION: When a collision determination part 11 determines that collision of a vehicle has occurred, and when a value of a deceleration G signal exceeds a prescribed operation threshold of the deceleration G or a yaw rate differential value exceeds a prescribed operation threshold of the yaw rate differential value, an expansion determination part 13 determines necessity to operate an airbag. Meanwhile, if the value of deceleration G signal is below the operation threshold value of the yaw rate differential value, and a yaw rate differential value is below the operation threshold of deceleration G the expansion determination part 13 determines that the airbag is not needed to operate.

Description

  The present invention relates to an occupant protection control device that controls the operation of an occupant protection device.

  Vehicles such as passenger cars are equipped with occupant protection devices such as airbags and seat belt pretensioners in order to protect occupants in the event of a collision.

  A vehicle equipped with this occupant protection device is provided with a longitudinal G sensor that detects acceleration in the longitudinal direction of the vehicle. The output of the front and rear G sensors is input to a microcomputer. For example, when the integral value of acceleration detected by the front-rear G sensor exceeds a predetermined threshold, the microcomputer determines that a severe vehicle collision has occurred and activates the occupant protection device.

  However, when a collision with small compressive deformation in the longitudinal direction of the vehicle, such as an oblique collision or an offset collision, occurs, the acceleration value detected by the longitudinal G sensor is small, and the integrated value of the acceleration does not exceed the threshold. There is a possibility that it takes time until the value exceeds the threshold value.

  Therefore, in response to the acceleration value detected by the front and rear G sensors exceeding a predetermined value, the calculation of the integral value of acceleration is started, and the integral value is multiplied by a coefficient corresponding to the elapsed time from the start of the calculation. When the multiplication value obtained in this way exceeds a threshold value, a configuration has been proposed in which it is determined that a collision to activate the occupant protection device has occurred. In addition, a G sensor that detects acceleration in the left-right direction and the vertical direction of the vehicle as well as the front-rear direction (traveling direction) of the vehicle is additionally provided, and the occupant protection device is operated based on the output of the G sensor. A configuration for determining that a power collision has occurred has been proposed.

JP-A-8-40190 JP 2000-335364 A

  However, the former configuration does not directly detect a collision other than a frontal collision such as an oblique collision or an offset collision, and the responsiveness of the operation of the occupant protection device is not necessarily limited to the occurrence of a collision other than a frontal collision. It does not always improve. On the other hand, the latter configuration requires a large number of G sensors, resulting in an increase in cost and space.

  An object of the present invention is to provide an occupant protection control device capable of improving the responsiveness of the occupant protection device operation against a collision other than a frontal collision such as an oblique collision or an offset collision without increasing the number of acceleration sensors. That is.

  In order to achieve the above object, an occupant protection control device according to the present invention is applied to a vehicle including an occupant protection device that protects an occupant during a collision and a yaw rate sensor used for vehicle behavior control. The occupant protection control device determines whether or not a vehicle collision has occurred based on a longitudinal acceleration sensor that detects longitudinal acceleration of the vehicle and an output waveform of the longitudinal acceleration sensor. Means, yaw rate differential value calculating means for calculating a yaw rate differential value detected by the yaw rate sensor, and the collision determination means determining that the vehicle has collided and obtaining from the output of the longitudinal acceleration sensor An operation for operating the occupant protection device in response to a physical quantity exceeding a predetermined acceleration operating threshold value or a differential value calculated by the yaw rate differential value calculating means exceeding a predetermined yaw rate differential operating threshold value. Means.

  Whether or not a vehicle collision has occurred is determined based on an output waveform of an acceleration sensor that detects acceleration in the longitudinal direction of the vehicle.

  When it is determined that a vehicle collision has occurred, it is determined whether or not the physical quantity obtained from the output of the longitudinal acceleration sensor exceeds a predetermined acceleration operation threshold value. When the physical quantity exceeds the acceleration operation threshold value, an occupant protection device that protects the occupant during a collision is activated. Thereby, when a frontal collision of the vehicle occurs and a large acceleration (deceleration) in the front-rear direction occurs in the vehicle, the occupant protection device can be operated.

  If the physical quantity obtained from the output of the longitudinal acceleration sensor does not exceed the acceleration actuation threshold, it is determined whether or not the yaw rate differential value detected by the yaw rate sensor exceeds a predetermined yaw rate differential actuation threshold. When the yaw rate differential value exceeds the yaw rate differential operation threshold, an occupant protection device that protects the occupant during a collision is activated. Thereby, even if the collision of the vehicle is an oblique collision or an offset collision and the longitudinal acceleration generated in the vehicle is small, the occupant protection device can be operated.

  Therefore, it is possible to improve the responsiveness of the operation of the occupant protection device against a collision other than a frontal collision such as an oblique collision or an offset collision without increasing the number of acceleration sensors.

  According to the present invention, not only when a frontal collision of a vehicle occurs, but also when an occupant needs to be protected not only when an oblique collision or an offset collision occurs, the occupant protection device is operated with a good response to the collision. be able to.

FIG. 1 is a block diagram showing a configuration of a main part of a vehicle provided with an occupant protection control device according to an embodiment of the present invention. FIG. 2 is a block diagram showing the configuration of the microcomputer. FIG. 3 is a flowchart showing the flow of the airbag operation process. FIG. 4 is a graph showing temporal changes of each deceleration G (deceleration acceleration) at the time of frontal collision and oblique collision of the vehicle. FIG. 5 is a graph showing the time change of the yaw rate differential value at the time of frontal collision and oblique collision of the vehicle.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a block diagram showing a configuration of a main part of a vehicle provided with an occupant protection control device according to an embodiment of the present invention.

  The vehicle 1 is equipped with an airbag 2 as an occupant protection device that protects the occupant during a collision. The airbag 2 is disposed, for example, in front of the driver seat and the passenger seat. As an occupant protection device, a seat belt pretensioner can be exemplified in addition to the airbag 2. The vehicle 1 may be equipped with a seat belt pretensioner instead of the airbag 2 or together with the airbag 2.

  Further, the vehicle 1 is provided with an airbag ECU (electronic control unit) 3 for controlling the operation of the airbag 2. The airbag ECU 3 is disposed, for example, at the front part in the vehicle interior.

  The airbag ECU 3 includes a microcomputer 4 including a CPU, a ROM, a RAM, and the like, and a drive circuit 6 for driving a squib (ignition device) 5 of the airbag 2.

  The vehicle 1 is also provided with a longitudinal G sensor 7 for detecting the longitudinal acceleration of the vehicle 1 and a yaw rate sensor 8 for detecting the yaw rate of the vehicle 1 (rotational angular velocity about the axis extending in the vertical direction). .

  The deceleration G signal output from the front / rear G sensor 7 and the yaw rate signal output from the yaw rate sensor 8 are input to the microcomputer 4 of the airbag ECU 3.

  The microcomputer 4 determines the necessity of the operation (deployment) of the airbag 2 based on the deceleration G signal input from the front / rear G sensor 7 and the yaw rate signal input from the yaw rate sensor 8. When it is necessary to operate the airbag 2, the microcomputer 4 controls the drive circuit 6 to supply a drive current from the drive circuit 6 to the squib 5. As a result, the squib 5 is ignited, high pressure gas is generated by the ignition of the gas generating agent, and the airbag 2 is instantly inflated.

  FIG. 2 is a block diagram showing the configuration of the microcomputer.

  The microcomputer 4 includes a collision determination unit 11, a differential operation unit 12, and a development determination unit 13 as function processing units realized in software by program processing.

  A deceleration G signal from the front / rear G sensor 7 is input to the collision determination unit 11 after passing through a low-pass filter for removing noise components. The collision determination unit 11 determines whether or not a collision of the vehicle 1 has occurred based on the waveform of the deceleration G signal. For example, when the value of the deceleration G signal (deceleration acceleration) exceeds a predetermined collision threshold, it is determined that a collision of the vehicle 1 has occurred.

  A yaw rate signal from the yaw rate sensor 8 is input to the differential operation unit 12. The differential calculation unit 12 calculates a yaw rate differential value (yaw angular acceleration) that is a differential value of the value of the yaw rate signal (yaw rate).

  A deceleration G signal from the front / rear G sensor 7 is input to the development determination unit 13 after passing through a low-pass filter for removing noise components. Further, the determination result by the collision determination unit 11 and the calculation result by the differential calculation unit 12 are input to the deployment determination unit 13. The deployment determination unit 13 determines whether or not the airbag 2 needs to be operated based on those inputs. Specifically, when the collision determination unit 11 determines that a collision of the vehicle 1 has occurred, the value of the deceleration G signal exceeds a predetermined operating threshold value for the deceleration G, or the yaw rate differential value is yaw rate. If the predetermined operation threshold value for the differential value is exceeded, the deployment determination unit 13 determines that the airbag 2 needs to be operated. On the other hand, if the value of the deceleration G signal is less than or equal to the operation threshold value for the deceleration G and the yaw rate differential value is less than or equal to the operation threshold value for the yaw rate differential value, the deployment determination unit 13 needs to operate the airbag 2. Judge that there is no.

  The flow of the above program processing (airbag operation processing) is shown in the flowchart of FIG. FIG. 4 is a graph showing temporal changes of each deceleration G (deceleration acceleration) at the time of frontal collision and oblique collision of the vehicle. FIG. 5 is a graph showing the time change of the yaw rate differential value at the time of frontal collision and oblique collision of the vehicle.

  As shown in FIG. 3, while the vehicle 1 is traveling, the microcomputer 4 repeatedly checks whether or not the deceleration G exceeds a predetermined collision threshold. As shown in FIG. 4, regardless of whether a frontal collision or an oblique collision of the vehicle 1 occurs, a deceleration G that is much larger than the deceleration G generated by the brake operation occurs, and the deceleration G exceeds the collision threshold. Therefore, when the deceleration G detected by the front / rear G sensor 7 (the value of the deceleration G signal after passing through the low-pass filter) exceeds the collision threshold, it is determined that a collision of the vehicle 1 has occurred.

  In FIG. 4, the time change of the deceleration G at the time of a frontal collision is indicated by a solid line, and the time change of the deceleration G at the time of an oblique collision is indicated by a two-dot chain line.

  If it is determined that no collision of the vehicle 1 has occurred (NO in step S1), the processing shown in FIG. 3 is immediately terminated.

  As shown in FIG. 3, when it is determined that a collision of the vehicle 1 has occurred (YES in step S <b> 1), the deceleration G detected by the front-rear G sensor 7 by the microcomputer 4 is a predetermined value for the deceleration G. It is determined whether or not the operating threshold (acceleration operating threshold) is exceeded (step S2). As shown in FIG. 4, the operation threshold value for the deceleration G is larger than the deceleration G generated in the vehicle 1 due to the oblique collision or the offset collision, and is caused by a severe frontal collision to some extent that the airbag 2 needs to be operated. A value smaller than the deceleration G generated in the vehicle 1 is set.

  Therefore, when the deceleration G exceeds the operation threshold for the deceleration G (YES in step S2), the airbag 2 is immediately deployed (step S3).

  If the deceleration G does not exceed the operation threshold for the deceleration G (NO in step S2), then the yaw rate differential value (yaw rate differential value) detected by the yaw rate sensor 8 is a predetermined value for the yaw rate differential value. It is determined whether or not the operating threshold (yaw rate differential operating threshold) is exceeded (step S4). As shown in FIG. 5, the actuation threshold value for the yaw rate differential value is a value larger than the yaw rate differential value generated in the vehicle 1 due to the frontal collision, and a severe oblique collision or offset that requires the airbag 2 to be actuated to some extent. It is set to a value smaller than the yaw rate differential value generated in the vehicle 1 by the collision.

  Therefore, if the yaw rate differential value exceeds the operating threshold for the yaw rate differential value (YES in step S4), the airbag 2 is immediately deployed (step S3).

  In FIG. 5, the time change of the yaw rate differential value at the time of the frontal collision is indicated by a solid line, and the time change of the yaw rate differential value at the time of the oblique collision is indicated by a two-dot chain line.

  Even if it is determined that a collision of the vehicle 1 has occurred, the value of the deceleration G signal is equal to or less than the operation threshold for the deceleration G (NO in step S3), and the yaw rate differential value is about the yaw rate differential value. If it is equal to or lower than the operation threshold (NO in step S4), the airbag 2 is not deployed.

  Thus, not only when the collision of the vehicle 1 is a severe frontal collision, but also when the collision of the vehicle 1 is an oblique collision or an offset collision and the front and rear G generated in the vehicle 1 is small, the occupant is protected. If necessary, the airbag 2 can be activated.

  Therefore, the response of the operation of the airbag 2 to a collision other than a frontal collision such as an oblique collision or an offset collision can be improved without increasing the number of acceleration sensors.

  As mentioned above, although one Embodiment of this invention was described, this invention can also be implemented with another form.

  For example, in the above-described embodiment, whether or not the vehicle 1 has collided is determined based on whether or not the deceleration G detected by the front and rear G sensor 7 exceeds the collision threshold. When the detected integral value of the deceleration G exceeds a predetermined first threshold value, it may be determined that a collision of the vehicle 1 has occurred.

  Further, whether or not the airbag 2 needs to be actuated is determined based on whether or not the deceleration G detected by the front-rear G sensor 7 exceeds the deceleration G threshold. However, the deceleration G detected by the front-rear G sensor 7 is determined. The airbag 2 may be immediately deployed when the integrated value of exceeds the second threshold value greater than the first threshold value.

  In addition, various design changes can be made to the above-described configuration within the scope of the matters described in the claims.

1 Vehicle 2 Airbag (Occupant Protection Device)
3 Airbag ECU (Occupant Protection Control Device)
6 Drive circuit (actuating means)
7 Longitudinal G sensor (Longitudinal acceleration sensor)
8 Yaw rate sensor 11 Collision judgment unit (collision judgment means)
12 Differential calculation unit (Yaw rate differential value calculation means)
13 Deployment determining unit (actuating means)

Claims (1)

An occupant protection control device that is applied to a vehicle equipped with an occupant protection device that protects an occupant during a collision and a yaw rate sensor used for vehicle behavior control, and that controls the operation of the occupant protection device,
A longitudinal acceleration sensor for detecting acceleration in the longitudinal direction of the vehicle;
A collision determination means for determining whether a collision of the vehicle has occurred based on an output waveform of the longitudinal acceleration sensor;
A yaw rate differential value calculating means for calculating a differential value of the yaw rate detected by the yaw rate sensor;
It is determined by the collision determination means that a collision of the vehicle has occurred, and the physical quantity obtained from the output of the longitudinal acceleration sensor exceeds a predetermined acceleration operation threshold value or is calculated by the yaw rate differential value calculation means An occupant protection control device including an activating means for activating the occupant protection device in response to a differential value exceeding a predetermined yaw rate differential operation threshold value.

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