Vehicle safety control apparatus for avoiding collision

Abstract

A collision between a vehicle and an obstacle is estimated, and based on the estimation result, vehicle deceleration control is performed by a brake actuator to reduce the collision and vehicle wheel load is controlled by a suspension actuator.

Description

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a view illustrating a configuration of a vehicle having mounted therein a safety control apparatus for avoiding collision according to Embodiment 1 of the present invention;

FIG. 2 is a circuit diagram of a brake hydraulic drive unit of a brake actuator of the vehicle having mounted therein the safety control apparatus for avoiding collision according to Embodiment 1;

FIG. 3 is a block diagram illustrating a servo control system of the brake actuator of the vehicle having mounted therein the safety control apparatus for avoiding collision according to Embodiment 1;

FIG. 4 is a circuit diagram of a suspension actuator of the vehicle having mounted therein the safety control apparatus for avoiding collision according to Embodiment 1;

FIG. 5 is a view illustrating flux-current characteristics of a supply/drain valve used in the suspension actuator of the vehicle having mounted therein the safety control apparatus for avoiding collision according to Embodiment 1;

FIG. 6 is a flowchart illustrating a vehicle height adjustment control processing flow performed by the suspension actuator of the vehicle having mounted therein the safety control apparatus for avoiding collision according to Embodiment 1;

FIG. 7 is a block diagram illustrating a servo control system of the suspension actuator of the vehicle having mounted therein the safety control apparatus for avoiding collision according to Embodiment 1;

FIG. 8 is a block diagram illustrating details of a collision determination unit of the safety control apparatus for avoiding collision according to Embodiment 1;

FIG. 9 is a flowchart illustrating a processing flow of steering unavoidable-collision determination performed by the collision determination unit of the safety control apparatus for avoiding collision according to Embodiment 1;

FIG. 10 is a flowchart illustrating a processing flow of braking unavoidable-collision determination performed by the collision determination unit of the safety control apparatus for avoiding collision according to Embodiment 1;

FIG. 11 is a flowchart illustrating a processing flow of steering unavoidable-collision likelihood determination performed by the collision determination unit of the safety control apparatus for avoiding collision according to Embodiment 1;

FIG. 12 is a flowchart illustrating a processing flow of braking unavoidable-collision likelihood determination performed by the collision determination unit of the safety control apparatus for avoiding collision according to Embodiment 1;

FIG. 13 is a flowchart illustrating an example of target vehicle height calculation of a suspension control unit in the safety control apparatus for avoiding collision according to Embodiment 1;

FIG. 14 is a time chart illustrating an example of target vehicle height calculation of a suspension control unit in the safety control apparatus for avoiding collision according to Embodiment 1;

FIG. 15 is a flowchart illustrating a processing flow of target deceleration calculation of a brake control unit in the safety control apparatus for avoiding collision according to Embodiment 1;

FIG. 16 is a time chart illustrating another example of target vehicle height calculation of the suspension control unit in the safety control apparatus for avoiding collision according to Embodiment 1;

FIG. 17 is a view illustrating a configuration of a vehicle having mounted therein a safety control apparatus for avoiding collision according to Embodiment 2 of the present invention;

FIG. 18 is a view illustrating a configuration of a suspension system of the vehicle having mounted therein the safety control apparatus for avoiding collision according to Embodiment 2;

FIG. 19 is a view illustrating a configuration of a damping coefficient variable type shock absorber of the suspension system of the vehicle having mounted therein the safety control apparatus for avoiding collision according to Embodiment 2;

FIG. 20 is a characteristic chart illustrating a relationship between pilot valve travel amount and damping coefficient of the damping coefficient variable type shock absorber of the suspension system of the vehicle having mounted therein the safety control apparatus for avoiding collision according to Embodiment 2;

FIG. 21 is a flowchart illustrating an exemplary processing flow of a suspension control unit performing setting of soft expansion and hard contraction in the safety control apparatus for avoiding collision according to Embodiment 2;

FIG. 22 is a view for explaining an effect of performing setting of soft expansion and hard contraction; and

FIG. 23 is a flowchart illustrating another exemplary processing flow of the suspension control unit performing setting to soft expansion and hard contraction in the safety control apparatus for avoiding collision according to Embodiment 2;

Claims

1. A safety control apparatus for avoiding collision used in a vehicle comprising: a headway distance/relative speed detection unit measuring a distance and relative speed between the vehicle and an obstacle;a collision determination unit estimating and determining a collision with the obstacle based on the distance and relative speed measured by the headway distance/relative speed detection unit;a brake actuator controlling a brake to perform deceleration; anda suspension actuator controlling a suspension to vary one of or both a vehicle height and a damping coefficient of a shock absorber,wherein the collision estimation and determination is performed by the collision determination unit, whereby the vehicle deceleration control by applying the brake is performed by the brake actuator to reduce impact upon collision and along with the deceleration control, vehicle wheel load is controlled by the suspension actuator.

2. The safety control apparatus for avoiding collision according to claim 1, wherein prior to the collision estimation and determination by the collision determination unit, collision likelihood determination is performed by the collision determination unit, and when it is determined that a collision is likely, the vehicle wheel load control is initiated by the suspension actuator prior to the deceleration control by the brake actuator.

3. A safety control apparatus for avoiding collision used in a vehicle comprising: a headway distance/relative speed detection unit measuring a distance and relative speed between the vehicle and an obstacle;a collision determination unit estimating and determining a collision with the obstacle based on the distance and relative speed measured by the headway distance/relative speed detection unit; a brake actuator controlling a brake to perform deceleration; anda suspension actuator controlling a suspension to vary a vehicle height,wherein the collision estimation and determination is performed by the collision determination unit, whereby the vehicle deceleration control by applying the brake is performed by the brake actuator to reduce impact upon collision and along with the deceleration control, vehicle height adjustment control of gradually raising a vehicle height of the vehicle is performed by the suspension actuator.

4. The safety control apparatus for avoiding collision according to claim 3, wherein prior to the collision estimation and determination by the collision determination unit, collision likelihood determination is performed by the collision determination unit, and when it is determined that a collision is likely, a vehicle height is preliminarily lowered and thereafter, there is performed vehicle height adjustment control of gradually raising a vehicle height of the vehicle when the brake is applied based on the collision estimation and determination.

5. The safety control apparatus for avoiding collision according to claim 4, wherein prior to the collision estimation and determination by the collision determination unit, the collision likelihood determination is performed in accordance with a length of time taken to vary a current vehicle height to a lowest vehicle height.

6. The safety control apparatus for avoiding collision according to claim 3, wherein when a brake operation is started by a driver before deceleration control is initiated by the brake actuator based on the collision estimation and determination by the collision determination unit, vehicle height adjustment control of gradually raising a vehicle height is performed starting just after the driver starts the brake operation.

7. The safety control apparatus for avoiding collision according to claim 3, wherein the vehicle height adjustment control of gradually raising a vehicle height by the suspension actuator is performed by a different rate of change of vehicle height in accordance with a suspension position of each wheel.

8. The safety control apparatus for avoiding collision according to claim 3, wherein when the brake is applied based on the collision estimation and determination by the collision determination unit, there is performed vehicle height adjustment control of gradually raising a vehicle height and then changing back the vehicle height into normal around a collision time.

9. The safety control apparatus for avoiding collision according to claim 3, wherein when the brake is applied based on the collision estimation and determination by the collision determination unit, there is performed vehicle height adjustment control of gradually raising a vehicle height and then adjusting the vehicle height to maximum around a collision time.

10. A safety control apparatus for avoiding collision used in a vehicle comprising: a headway distance/relative speed detection unit measuring a distance and relative speed between the vehicle and an obstacle;a collision determination unit estimating and determining a collision with the obstacle based on the distance and relative speed measured by the headway distance/relative speed detection unit; a brake actuator controlling a brake to perform deceleration; anda suspension actuator controlling a suspension to vary a damping coefficient of a shock absorber, wherein the collision estimation and determination is performed by the collision determination unit, whereby vehicle deceleration control by applying the brake is performed by the brake actuator to reduce impact upon collision and along with the deceleration control, control of varying a damping coefficient of the shock absorber is performed by the suspension actuator.

11. The safety control apparatus for avoiding collision according to claim 10, wherein along with the deceleration control, control of setting a damping coefficient of the shock absorber to soft expansion and hard contraction is performed by the suspension actuator.

12. The safety control apparatus for avoiding collision according to claim 10, wherein along with the deceleration control, the following control is performed by the suspension actuator; that is, a damping coefficient of the shock absorber in a front side is set to soft expansion and hard contraction, and a damping coefficient of the shock absorber in a rear side is set to hard expansion and soft contraction.

13. The safety control apparatus for avoiding collision according to claim 10, wherein prior to the collision estimation and determination by the collision determination unit, collision likelihood determination is performed by the collision determination unit, and when it is determined that a collision is likely, control of varying a damping coefficient of the shock absorber is preliminarily performed by the suspension actuator.