JP2008149933A - Braking control device in vehicle rear-end collision - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a braking control device in vehicle rear-end collision capable of reducing damage to an occupant even when rear-end collision load is excessively large to a degree that it cannot be absorbed by deformation of an impact absorption structure of a rear part of the vehicle when the vehicle is stopped or in speed-reduction immediately before stopping. <P>SOLUTION: The braking control device 1 in the vehicle rear-end collision is provided with: a vehicle speed sensor 9 for detecting a traveling speed of the vehicle and outputting a speed signal; an acceleration sensor 10 for detecting the rear-end collision of the following vehicle to the vehicle and outputting a rear-end collision load signal; and a braking control part 5 for determining that the traveling speed of the vehicle is a low speed or zero based on the speed signal and applying braking to a wheel of the vehicle when it is determined that the rear-end collision load of the following vehicle is inputted to the vehicle from the rear-end collision load signal. Further, the braking control part 5 release the braking of the wheel when it is determined from the rear-end collision load signal that the rear-end collision load is out of the range capable of being absorbed by the impact absorption structure of the rear part of the vehicle. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vehicle rear-end collision braking control device that applies a brake to a wheel under a predetermined condition when a rear-end vehicle collides.

  Conventionally, when the vehicle is stopped or decelerated and immediately before stopping, the rear vehicle rear-end collision braking control has been made to avoid as much as possible the collision of the front vehicle with a rear-end collision. An apparatus is known (see, for example, Patent Document 1).

  By the way, in a vehicle such as a passenger car, an impact absorbing structure is provided at the rear so that when a subsequent vehicle collides at the rear and a rear collision load is input, the rear is deformed by the rear collision and the rear collision can be absorbed. It is normal.

This shock absorbing structure is provided in order to reduce damage to the occupant due to rear-end collision load when a subsequent vehicle collides with the rear portion of the vehicle. This impact absorbing structure at the rear part of the vehicle is effective even when it is collided with a succeeding vehicle when the vehicle is stopped, or when the vehicle is stopped or decelerated by a brake and immediately before stopping, as long as it can be absorbed by deformation.
JP 2005-145328 A

  However, when the vehicle is stopped or just before the vehicle is decelerated and stopped, if the rear-end collision load is too large to be absorbed by the deformation of the shock absorbing structure at the rear of the vehicle, there is a risk of damaging the occupant.

  Accordingly, the present invention provides a vehicle rear portion that can reduce damage to the occupant even when the vehicle is stopped or decelerated and immediately before stopping, even if the rear-end collision load is too large to be absorbed by the deformation of the shock absorbing structure at the rear of the vehicle. It is an object of the present invention to provide a rear-end collision braking control device.

  To achieve this object, the present invention provides vehicle speed detection means for detecting a traveling speed of a vehicle and outputting a speed signal, and rear-end collision detection for detecting a rear-end collision of a succeeding vehicle to the vehicle and outputting a rear-end collision load signal. And when it is determined that the traveling speed of the vehicle is low or zero based on the speed signal and the rear-end collision load of the following vehicle is input to the vehicle from the rear-end collision signal. Braking control means for braking the rear wheels of the vehicle, wherein the braking control means is outside the range in which the rear impact load can be absorbed by the rear shock absorbing structure of the vehicle. If it is determined from the rear-end collision load signal, the vehicle rear-end rear-end collision braking control device releases the wheel brake.

  According to this configuration, when the braking control unit determines that the traveling speed of the vehicle is low or zero based on the speed signal and determines that the rear-end collision load of the following vehicle is input to the vehicle from the rear-end collision load signal. Apply brakes to vehicle wheels. At this time, the brake control means releases the brake of the wheel when the rear-end collision signal determines that the rear-end collision load is out of the range that can be absorbed by the impact absorbing structure at the rear of the vehicle, so the vehicle is stopped. Even when the vehicle is decelerated by braking or just before stopping, the damage to the occupant can be reduced even if the rear-end collision load is too large to be absorbed by the deformation of the shock absorbing structure at the rear of the vehicle.

  Hereinafter, a vehicle rear-end collision braking control device according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 shows the overall configuration of a vehicle rear-end collision braking control device 1 according to the present invention. The vehicle rear-end collision braking control device 1 uses an airbag controller 3 that controls the operation of the airbag 2 for brake control of the vehicle. The airbag controller 3 is an arithmetic control circuit that controls the operation of the airbag 2 by a program for controlling the operation of the airbag. The airbag controller 3 includes an airbag control unit 4 and a braking control unit 5 as braking control means.

  The airbag control unit 4 controls the operation of the airbag 2. The braking control unit 5 includes a vehicle speed determination unit 6, a rear-end collision determination unit 7, and a front obstacle determination unit 8.

  Further, the vehicle rear-end collision braking control device 1 includes a vehicle speed sensor 9, an acceleration detection sensor (G sensor) 10 as an acceleration detection means, and an obstacle sensor as an obstacle detection means for detecting an obstacle ahead of the vehicle. 11. The vehicle speed sensor 9 detects the traveling speed of the vehicle and outputs a traveling speed signal.

  Furthermore, the acceleration detection sensor 10 detects a rear-end collision acceleration when a succeeding vehicle collides with the rear portion of the vehicle, and outputs an acceleration signal as a rear rear-end collision signal (a rear-end collision load signal). Since the acceleration detection sensor 10 can be a known G sensor, detailed description thereof is omitted.

  The airbag control unit 4 receives the acceleration signal from the acceleration detection sensor 10 (acceleration signal at the time of forward collision and rear rear collision) when the airbag control unit 4 receives the acceleration signal and the acceleration signal is greater than or equal to a predetermined value. 2 is activated. Since the control of the operation of the airbag 2 can employ a conventionally known technique, the description thereof is omitted.

  The obstacle sensor 11 outputs an output signal (including an obstacle detection signal and an obstacle non-detection signal) for determining whether or not there is an obstacle (for example, a vehicle) in front of the vehicle. Yes. As the obstacle sensor 11, a well-known sensor using radio waves, sound waves, light (other light such as infrared rays, near infrared rays) or the like can be adopted, and detailed description thereof will be omitted.

  The travel speed signal from the vehicle speed sensor 9 is input to the vehicle speed determination unit 6, the acceleration signal (rejection load signal) from the acceleration detection sensor 10 is input to the rear collision determination unit 7, and the output signal from the obstacle sensor 11 is It is input to the forward obstacle determination unit 8.

  The vehicle speed determination unit 6 determines whether the vehicle traveling speed is low (for example, 5 km / h or less) or zero, and outputs a low speed signal when the vehicle is low. Sometimes a stop signal is output. Further, the rear-end collision determination unit 7 is configured to output an acceleration signal (a rear-end collision load signal) from the acceleration detection sensor 10 as a rear-end collision signal at the time of a rear-end collision of the subsequent vehicle to the rear portion of the vehicle. Further, the forward obstacle determination unit 8 determines whether, for example, another vehicle exists as an obstacle in front of the vehicle from the output signal of the obstacle sensor 11, that is, the output signal of the obstacle sensor 11 is the obstacle. In the case of a detection signal, an obstacle presence signal is output.

  In addition, when the braking control unit 5 receives the low speed signal or the stop signal from the vehicle speed determination unit 6 and the acceleration signal (the rear collision load signal) is input as the rear collision signal from the acceleration detection sensor 10, the forced braking device 12 is driven to brake each wheel of the vehicle.

  The braking control unit 5 drives the forced braking device 12 to brake each wheel of the vehicle, and the obstacle presence signal from the front obstacle determining unit 8 (the obstacle sensor 11 When it is judged from the acceleration signal (the rear impact load signal) that the rear impact load is within the range that can be absorbed by the impact absorbing structure at the rear of the vehicle when the object detection signal is received, The brake is not released.

  In addition, the braking control unit 5 drives the forced braking device 12 to brake each wheel of the vehicle, and the rear-end collision load is outside the range that can be absorbed by the shock absorbing structure at the rear of the vehicle. When judged from the acceleration signal (the rear-end collision load signal), the brake to each wheel by the forced brake device 12 is released.

  Next, an operation flow of the vehicle rear-end collision braking control device having the above-described configuration will be described with reference to FIG.

A travel speed signal from the vehicle speed sensor 9 is input to the vehicle speed determination unit 6. The vehicle speed determination unit 6 determines whether the vehicle traveling speed is low (for example, 5 km / h or less) or zero, and outputs a low speed signal when the vehicle is low. Sometimes a stop signal is output. The low speed signal and stop signal from the vehicle speed determination unit 6 are input to the braking control unit 5.
Step S1
In step S1, the braking control unit 5 receives the acceleration signal (the rear-end collision load) from the acceleration detection sensor 10 at the time of the rear-end collision of the succeeding vehicle to the rear portion of the vehicle when receiving the low-speed signal or the stop signal from the vehicle speed determination unit 6. If the signal is received as a rear-end collision signal, the process proceeds to step S2.
Step S2
In step S2, when receiving the rear-end collision signal, the braking control unit 5 drives the forced braking device 12 to brake each wheel of the vehicle, and proceeds to step S3.
Step S3
In step S3, the braking control unit 5 determines whether there is an obstacle such as another vehicle in front of the vehicle. If there is an obstacle, the process proceeds to step S4, and if not, the process proceeds to step S6.

This determination is performed based on whether or not an obstacle detection signal is input from the obstacle sensor 11 to the front obstacle determination unit 8 and the front obstacle determination unit 8 outputs an obstacle presence signal.
Step S4
In this step S3, when the braking control unit 5 determines from the acceleration signal (the rear impact load signal) of the acceleration detection sensor 10 that the rear impact load is within the range that can be absorbed by the impact absorbing structure at the rear of the vehicle, the process proceeds to step S6. Then, when it is determined from the acceleration signal (the rear impact load signal) of the acceleration detection sensor 10 that the rear impact load is outside the range that can be absorbed by the impact absorbing structure at the rear of the vehicle, the process proceeds to step S5.
Step S5
In step S <b> 3, the braking control unit 5 releases the brake for each wheel of the vehicle by the forced brake device 12. Thereby, the damage given to the passenger | crew of a vehicle can be reduced.

That is, when a forcible brake device 12 forcibly brakes each wheel of the vehicle and a subsequent vehicle collides with the rear part of the vehicle, the rear-end collision load is absorbed by the impact absorbing structure at the rear part of the vehicle. If it is out of the possible range, the head of the occupant may be vigorously shaken back and forth, which may damage the occupant's head and neck. However, when the rear-end collision load is outside the range that can be absorbed by the shock absorbing structure at the rear of the vehicle, the brake for each wheel of the vehicle by the forced brake device 12 is released, and the vehicle can be moved to the front side by the rear-end collision load. Thus, since the vehicle moves forward when the rear-end collision occurs, it is possible to prevent the occupant's head from being shaken violently back and forth, and to reduce damage to the occupant's head and neck.
Step S6
In step S <b> 3, the braking control unit 5 stops the vehicle without releasing the brake for each wheel of the vehicle by the forced brake device 12 and prevents a secondary disaster.

  That is, when another vehicle exists in front of the vehicle as an obstacle and the subsequent vehicle collides with the rear part of the vehicle, if the brake for each wheel is released, the vehicle collides with the vehicle in front and the secondary disaster occurs. May also occur.

  However, when the succeeding vehicle collides with the rear part of the vehicle, if the rear-end collision load is within a range that can be absorbed by the shock absorbing structure at the rear part of the vehicle, the passenger's head is not shaken back and forth. In such a case, it is impossible to seriously damage the head or neck of the occupant without releasing the brake for each wheel when the succeeding vehicle collides with the rear of the vehicle. As a result, when another vehicle exists in front of the vehicle as an obstacle, it is possible to prevent the vehicle from colliding with the vehicle ahead and causing a secondary disaster by not releasing the brake for each wheel.

  In the embodiment described above, the airbag controller 3 is used to control the operation of the forced brake device 12. However, the present invention is not necessarily limited to this. For example, the operation control of the forced brake device 12 may be performed by a dedicated control circuit in which the airbag control unit 4 and the airbag 2 in FIG. 1 are omitted.

  As described above, the vehicle rear-end collision braking control device 1 according to the embodiment of the present invention detects vehicle travel speed and outputs a speed signal, and the vehicle speed detection means (vehicle speed sensor 9). A rear collision detection means (acceleration detection sensor 10) for detecting a rear collision of a succeeding vehicle and outputting a rear collision load signal; determining that the traveling speed of the vehicle is low or zero based on the speed signal; and And a braking control means (braking control unit 5) that applies a brake to the wheels of the vehicle when it is determined from the trailing load signal that the trailing load of the following vehicle is input to the vehicle. In addition, the braking control means (braking control unit 5) releases the brake of the wheel when it is determined from the rear-end collision load signal that the rear-end collision load is out of a range that can be absorbed by the shock absorbing structure at the rear of the vehicle. It is supposed to be.

  According to this configuration, the braking control means (braking control unit 5) determines that the traveling speed of the vehicle is low or zero based on the speed signal, and the rear-end collision load of the following vehicle is input to the vehicle from the rear-end collision signal. When it is determined that the vehicle has been released, the vehicle wheel is braked. At this time, when the braking control means (braking control unit 5) determines from the rear impact load signal that the rear impact load is outside the range that can be absorbed by the shock absorbing structure at the rear of the vehicle, the brake of the wheel is released. Even when the vehicle is stopped or decelerated by the brake and immediately before the vehicle stops, even if the rear-end collision load is too large to be absorbed by the deformation of the shock absorbing structure at the rear of the vehicle, damage to the occupant can be reduced.

  In the above-described embodiment, the acceleration detection sensor 10 that detects the collision of the succeeding vehicle to the vehicle and outputs the acceleration signal as the collision load signal is used as the rear collision detection unit. It is not a thing. For example, if a strain gauge is provided in the shock absorbing structure part at the rear of the vehicle, and the impact absorbing structure part at the rear of the vehicle is deformed during the rear-end collision of the following vehicle with the rear part of the vehicle, the shock absorbing structure part is deformed. It may be detected by a change in the output (resistance value) from the strain gauge, and a rear-end collision may be detected from this change, and the rear-end collision weight may be obtained from the strain change speed.

  The vehicle rear-end collision braking control device 1 according to the embodiment of the present invention includes an obstacle sensor 11 that detects an obstacle ahead and outputs an obstacle detection signal. Moreover, when the braking control means (braking control unit 5) detects the presence of an obstacle from the obstacle detection signal, the rear-end collision load is within a range that can be absorbed by the shock absorbing structure at the rear of the vehicle. When it is determined from the rear-end collision load signal, the brake of the wheel is not released. Further, the braking control means (braking control unit 5), when judging from the rear impact load signal that the rear impact load is outside the range that can be absorbed by the impact absorbing structure at the rear of the vehicle, It comes to cancel.

  According to this configuration, when the rear-end collision load is within a range that can be absorbed by the rear shock absorbing structure of the vehicle, damage to the occupant can be reduced and a secondary disaster such as rear-end collision with another vehicle can be prevented. In addition, when the rear-end collision is outside the range that can be absorbed by the shock absorption structure at the rear of the vehicle, the brakes for each wheel of the vehicle are released and the vehicle can be moved forward by the rear-end collision so that the rear-end collision occurs. Since the vehicle moves forward, the head of the occupant can be prevented from being shaken violently back and forth, and damage to the occupant's head and neck can be reduced.

  Further, in the vehicle rear-end collision braking control apparatus 1 according to the embodiment of the present invention, the rear-end collision detection means detects the rear-end collision of the following vehicle to the vehicle and outputs an acceleration signal as a rear-end collision load signal. It is.

  According to this configuration, it is possible to detect a rear-end collision load using the acceleration detection sensor 10 necessary for controlling the airbag 2.

1 is an overall configuration diagram of a vehicle rear-end collision control device according to the present invention. It is the flowchart which showed operation | movement of the vehicle rear part collision control apparatus which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Vehicle rear part rear-end collision braking control apparatus 5 ... Brake control part (braking control means)
9 ... Vehicle speed sensor (vehicle speed detection means)
10 ... Acceleration detection sensor (rear collision detection means)
11 ... Obstacle sensor

Claims (3)

Vehicle speed detecting means for detecting a traveling speed of the vehicle and outputting a speed signal; Rear collision detecting means for detecting a rear collision of a succeeding vehicle to the vehicle and outputting a rear collision load signal; and the vehicle based on the speed signal Braking control means for applying a brake to the wheels of the vehicle when it is determined that the traveling speed of the vehicle is low or zero, and it is determined from the collision load signal that the rear-end collision load of the following vehicle is input to the vehicle. A vehicle rear-end collision braking control device comprising:
The vehicle rear portion characterized in that the braking control means releases the brake of the wheel when it is determined from the rear impact load signal that the rear impact load is outside the range that can be absorbed by the impact absorbing structure of the rear portion of the vehicle. Rear-end braking control device. The vehicle rear-end collision braking control device according to claim 1, wherein the vehicle includes an obstacle sensor that detects an obstacle ahead and outputs an obstacle detection signal.
When the braking control means detects the presence of an obstacle from the obstacle detection signal, if the collision load is within a range that can be absorbed by the impact absorbing structure at the rear of the vehicle, When it is determined from the collision load signal that the brake of the wheel is not released and the collision load is outside the range that can be absorbed by the shock absorbing structure at the rear of the vehicle, A braking control device for rear-end collision of a vehicle, wherein the brake is released.   The rear rear collision braking control device according to claim 1 or 2, wherein the rear rear collision detection means is an acceleration detection sensor that detects a rear collision of a succeeding vehicle to the vehicle and outputs an acceleration signal as a rear collision load signal. A vehicle rear-end collision braking control device characterized by the above.

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