Active safety apparatus

1. An active safety device for a motor vehicle comprising:

obstacle detection device for detecting an obstacle;

vehicle path prediction device for predicting a future path of the vehicle;

collision possibility calculation device for calculating the possibility of a collision between the vehicle and the obstacle; and

collision responding device for informing a driver of the presence of the obstacle or controlling the vehicle so as not to approach the obstacle according to the possibility of the collision between the vehicle and the obstacle,

wherein the device further comprises:

obstacle storage device for storing a position of the obstacle; and

position estimation device for estimating a relative position between the vehicle and the obstacle based upon the position of the obstacle stored by the obstacle storage device, a vehicle speed of the vehicle, a yaw angular velocity of the vehicle, and a vehicle sideslip angle defined as an angle of vehicle center of gravity in a traveling direction relative to a longitudinal axis on a fixed coordinate system of the vehicle.

2. The active safety device for a motor vehicle according to claim 1 , wherein the position estimation device estimates a relative position between an obstacle that cannot be detected at present by the obstacle detection device and the vehicle from the position of the obstacle stored by the obstacle storage device, the vehicle speed of the vehicle, the yaw angular velocity of the vehicle, and the sideslip angle of the vehicle.

3. The active safety device for a motor vehicle according to claim 1 , wherein the position estimation device estimates a present position of the vehicle from the vehicle speed of the vehicle, the yaw angular velocity of the vehicle, and the sideslip angle of the vehicle.

4. The active safety device for a motor vehicle according to claim 1 , wherein the position estimation device estimates a relative position between a tire of the vehicle and the obstacle from the position of the obstacle stored by the obstacle storage device, the vehicle speed of the vehicle, the yaw angular velocity of the vehicle, the sideslip angle of the vehicle, and a relative position between a vehicle body and the tire of the vehicle.

5. The active safety device for a motor vehicle according to claim 1 , wherein the obstacle storage device changes a cycle of storing the position of the obstacle according to the vehicle speed of the vehicle.

6. The active safety device for a motor vehicle according to claim 1 , further comprising obstacle storage elimination device for eliminating storage of one obstacle when stored two obstacles are positioned close to each other.

7. The active safety device for a motor vehicle according to claim 1 , wherein the obstacle storage device changes the number of obstacles to be stored according to the vehicle speed of the vehicle.

8. The active safety device for a motor vehicle according to claim 1 , further comprising sideslip angle estimation device for estimating a sideslip angle of the vehicle from the vehicle speed of the vehicle, a steering angle of the vehicle, and/or the yaw angular velocity of the vehicle.

9. A method for active safety of a motor vehicle comprising:

detecting an obstacle;

storing a position of the obstacle;

estimating a relative position between the vehicle and the obstacle based on the stored position of the obstacle, a speed of the vehicle, a yaw angular velocity of the vehicle, and a vehicle sideslip angle defined as an angle of vehicle center of gravity in a traveling direction relative to a longitudinal axis on a fixed coordinate system of the vehicle;

predicting a future path of the vehicle;

calculating possibility of a collision between the vehicle and the obstacle from the estimated relative position of the vehicle and the obstacle and the predicted future path of the vehicle; and

informing a driver of the presence of the obstacle or controlling the vehicle so as not to approach the obstacle according to the possibility of the collision between the vehicle and the obstacle.

10. The method for active safety of a motor vehicle according to claim 9 , wherein the estimating step estimates a relative position between an obstacle that cannot be detected at present by the detecting step and the vehicle from the stored position of the obstacle, the speed of the vehicle, the yaw angular velocity of the vehicle, and the sideslip angle of the vehicle.

11. The method for active safety of a motor vehicle according to claim 9 , wherein the estimating step estimates a present position of the vehicle from the speed of the vehicle, the yaw angular velocity of the vehicle, and the sideslip angle of the vehicle.

12. The method for active safety of a motor vehicle according to claim 9 , wherein the estimating step estimates a relative position between a tire of the vehicle and the obstacle from the stored position of the obstacle, the speed of the vehicle, the yaw angular velocity of the vehicle, the sideslip angle of the vehicle, and a relative position between a vehicle body and the tire of the vehicle.

13. The method for active safety of a motor vehicle according to claim 9 , wherein the storing step includes changing a cycle of storing the position of the obstacle according to the speed of the vehicle.

14. The method for active safety of a motor vehicle according to claim 9 , further comprising eliminating storage of one obstacle when stored two obstacles are positioned close to each other.

15. The method for active safety of a motor vehicle according to claim 9 , wherein the storing step includes changing the number of obstacles to be stored according to the speed of the vehicle.

16. The method for active safety of a motor vehicle according to claim 9 , further comprising estimating a sideslip angle of the vehicle from the speed of the vehicle, a steering angle of the vehicle, and/or the yaw angular velocity of the vehicle.