Device for controlling turn behavior of vehicle

• US 5,627,756 A
• Filed: 06/02/1995
• Issued: 05/06/1997
• Est. Priority Date: 07/28/1994
• Status: Expired due to Term

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Inagaki, Shoji, Fukada, Yoshiki
• Primary Examiner(s): Teska, Kevin J.
• Assistant Examiner(s): Walder, Jr., Stephen J.
• Application Number:
  US08/459,968
• Time in Patent Office: 704 Days
• Field of Search: 364/426.03, 364/426.01, 364/426.02, 364/426.04, 364/426.05, 180/197, 180/282
• US Class Current: 701/70
• CPC Class Codes: B60T 2220/03 Driver counter-steering; Avoidance of conflicts with ESP control
• CPC Class Codes: B60T 8/1755 Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve road vehicle drive control systems for control of driving stability otherwise than by controlling a particular sub-unit B60W30/02
• CPC Class Codes: B60T 8/348 4 Channel systems B60T8/345 takes precedence
• CPC Class Codes: B60T 8/445 replenishing the released brake fluid volume into the brake piping
• CPC Class Codes: G05D 1/0891 specially adapted for land vehicles

Abstract

To control turn behavior of a vehicle such as an automobile more effectively and desirably by presuming the turn behaving of the vehicle at higher precision, a turn behavior control device detects lateral acceleration Gy of a vehicle body, vehicle speed V and yaw rate r of the vehicle body, then calculates lateral slide velocity Vy of the vehicle by integrating deviation Gy-Vr according to a predetermined integration time constant, then presumes the turn behavior of the vehicle based upon at least the lateral slide velocity Vy, and then controls the turn behavior of the vehicle based upon the presumed turn behavior. When the turn behavior of the vehicle is presumed to be stable, the integration time constant is made small to decrease accumulation of errors, whereas when the turn behavior of the vehicle is presumed to be unstable, the integration time constant is made large so as to definitely execute the behavior control.

Claims

1. A device for controlling behavior of a vehicle, comprising means for detecting lateral acceleration Gy of a vehicle body, means for detecting vehicle speed V, means for detecting yaw rate r of the vehicle body, means for presuming turn behavior of the vehicle based upon at least lateral slide velocity Vy of the vehicle by obtaining the lateral slide velocity Vy through integration of deviation Gy-Vr with a predetermined integration time constant, and means for controlling turn behavior of the vehicle based upon the presumed turn behavior, wherein said turn behavior presuming means includes means for varying said integration time constant such that said integration time constant is set to be smaller when a stable turn behavior of the vehicle is presumed than when an unstable turn behavior of the vehicle is presumed.

2. A device for controlling behavior of a vehicle, comprising means for detecting lateral acceleration Gy of a vehicle body, means for detecting vehicle speed V, means for detecting yaw rate r of the vehicle body, means for presuming turn behavior of the vehicle based upon at least lateral slide velocity Vy of the vehicle by obtaining the lateral slide velocity Vy through integration of deviation Gy-Vr, and means for controlling turn behavior of the vehicle based upon the presumed turn behavior, wherein said turn behavior presuming means includes means for modifying the lateral slide velocity Vy such that the lateral slide velocity Vy is decreased when the direction of the lateral slide velocity Vy is in contradiction to the direction of other parameter of the vehicle from the view point of dynamics.

3. A device for controlling behavior of a vehicle, comprising means for detecting lateral acceleration Gy of a vehicle body, means for presuming turn behavior of the vehicle based upon at least the lateral acceleration Gy, and means for controlling turn behavior of the vehicle based upon the presumed turn behavior of the vehicle, wherein said turn behavior presuming means comprises means for detecting vehicle speed V, means for detecting yaw rate r of the vehicle body, means for calculating deviation Gy-Vr, means for calculating cant compensation quantity through low pass filtering of the deviation Gy-Vr, and means for modifying the lateral acceleration Gy according to the cant compensation quantity, the turn behavior of the vehicle being presumed based upon the modified lateral acceleration Gya.

4. A device according to claim 3, wherein said behavior presuming means comprises means for calculating lateral slide velocity Vy of the vehicle through integration of deviation Gya-Vr between the modified lateral acceleration Gya and Vr, means for presuming spin of the vehicle based upon the lateral slide velocity Vy, and means for modifying the cant compensation quantity to zero when the compensation by the cant compensation quantity increases the lateral slide velocity Vy in a condition that a spin of the vehicle is presumed.

5. A device for controlling behavior of a vehicle, comprising means for detecting lateral acceleration Gy of a vehicle body, means for detecting vehicle speed V, means for detecting yaw rate r of the vehicle body, means for presuming turn behavior of the vehicle based upon at least lateral slide velocity Vy by obtaining the lateral slide velocity Vy through integration of deviation Gy-Vr, and means for controlling turn behavior of the vehicle based upon the presumed turn behavior, wherein said turn behavior presuming means includes means for modifying the lateral acceleration Gy such that change rate thereof is decreased in obtaining the lateral slide velocity Vy when the absolute value of Gy is decreasing under a condition that the absolute value of the Gy is smaller than the absolute value of Vr.

6. A device for controlling behavior of a vehicle, comprising means for detecting lateral acceleration Gy of a vehicle body, means for presuming turn behavior of the vehicle based upon at least the lateral acceleration Gy, and means for controlling turn behavior of the vehicle based upon the presumed turn behavior, wherein said turn behavior presuming means comprises means for obtaining radius of curvature of road, means for presuming bank angle of road surface based upon the radius of curvature, and means for modifying the lateral acceleration Gy according to the presumed bank angle, the turn behavior of the vehicle being presumed based upon the modified lateral acceleration.

7. A device for controlling behavior of a vehicle, comprising means for detecting lateral acceleration Gy of a vehicle body, means for detecting vehicle speed V, means for detecting yaw rate r of the vehicle body, means for detecting steering angle θ

, means for calculating a first estimation quantity expressing lateral sliding of the vehicle based upon the lateral acceleration Gy, the vehicle speed V and the detected yaw rate r, means for calculating a second estimation quantity expressing deviation Δ

r between target yaw rate obtained from the steering angle θ and

the vehicle speed V and the detected yaw rate, means for presuming turn behavior of the vehicle based upon at least said first and second estimation quantities each weighed by individual weighing factor, and means for controlling turn behavior of the vehicle based upon the presumed turn behavior, wherein said turn behavior presuming means includes means for modifying said weighing factor such that said second estimation quantity is more weighed when a stable turn behavior of the vehicle is presumed, while said first estimation quantity is more weighed when an unstable turn behavior of the vehicle is presumed.

8. A device for controlling behavior of a vehicle, comprising means for detecting lateral acceleration Gy of a vehicle body, means for detecting vehicle speed V, means for detecting actual yaw rate r of the vehicle body, means for detecting steering angle θ

, means for calculating a first estimation quantity expressing lateral sliding of the vehicle based upon the lateral acceleration Gr, the vehicle speed V and the detected yaw rate r, means for calculating a second estimation quantity expressing deviation Δ

r between target yaw rate obtained from the steering angle θ and

the vehicle speed V and the detected actual yaw rate, means for presuming spin of the vehicle based upon at least said first and second estimation quantities, and means for controlling the turn behavior of the vehicle so as to decrease the spin based upon presumed spin, wherein said means for calculating said second estimation quantity is adapted to calculate target yaw rate with a predetermined cycle and to calculate said second estimation quantity by replacing the current target yaw rate by the target yaw rate at a preceding cycle when the steering angle θ

is changing toward further steering in a condition that a spin of the vehicle is presumed by the spin presuming means.

9. A device for controlling behavior of a vehicle, comprising means for detecting lateral acceleration Gy of a vehicle body, means for detecting vehicle speed V, means for detecting actual yaw rate r of the vehicle body, means for detecting steering angle θ

, means for calculating a first estimation quantity expressing lateral sliding of the vehicle based upon the lateral acceleration Gy, the vehicle speed V and the detected actual yaw rate r, means for calculating a second estimation quantity expressing deviation Δ

r between target yaw rate obtained from the steering angle θ and

the vehicle speed V and the actual yaw rate, means for presuming spin of the vehicle based upon at least said first and second estimation quantities, and means for controlling turn behavior of the vehicle so as to decrease the spin based upon the presumed spin, wherein said spin presuming means includes means for limiting said second estimation quantity not to be greater than a predetermined value when the detected actual yaw rate is smaller than the target yaw rate.

10. A device for controlling behavior of a vehicle, comprising means for detecting lateral acceleration Gy of a vehicle body, means for detecting vehicle speed V, means for detecting actual yaw rate r of the vehicle body, means for detecting steering angle θ

, means for calculating a first estimation quantity expressing lateral sliding of the vehicle based upon the lateral acceleration Gy, the vehicle speed V and the detected actual yaw rate r, means for calculating a second estimation quantity expressing deviation Δ

r between target yaw rate obtained from the steering angle θ and

the vehicle speed V and the detected actual yaw rate, means for presuming spin of the vehicle based upon at least said first and second estimation quantities, and means for controlling spin behavior of the vehicle so as to decrease the spin based upon the presumed spin, wherein said means for calculating said second estimation quantity comprises means for processing the target yaw rate obtained from the steering angle θ and

the vehicle speed V to incorporate a primary delay, and means for modifying time constant of the primary delay such that the time constant is set smaller when the target yaw rate after the primary delay processing is not between the target yaw rate before the primary delay processing and the detected actual yaw rate than when the target yaw rate after the primary delay processing is between the target yaw rate before the primary delay processing and the detected actual yaw rate.

11. A device for controlling behavior of a vehicle, comprising means for detecting lateral acceleration Gy, means for detecting vehicle speed V, means for detecting actual yaw rate r of the vehicle body, means for detecting steering angle θ

, means for calculating a first estimation quantity expressing lateral sliding of the vehicle based upon the lateral acceleration Gy, the vehicle speed V and the detected actual yaw rate r, means for calculating a second estimation quantity expressing deviation Δ

r between target yaw rate obtained from the steering angle θ and

the vehicle speed V and the detected actual yaw rate, means for presuming turn behavior of the vehicle based upon a final estimation quantity based upon at least said first and second estimation quantities, and means for controlling turn behavior of the vehicle according to a control amount depending upon said final estimation quantity based upon the presumed turn behavior of the vehicle, further comprising means for detecting wheel speeds of left and right front vehicle wheels, means for detecting actual longitudinal acceleration Gx of the vehicle, means for calculating presumed yaw rate rhat of the vehicle body based upon the wheel speeds of the left and right front vehicle wheels means for calculating presumed longitudinal acceleration Gxhat based upon the wheel speeds of the left and right front vehicle wheels, means for presuming level of road disturbance based upon the deviation between the detected actual yaw rate r and the presumed yaw rate rhat and the deviation between the actual longitudinal acceleration Gx and the presumed longitudinal acceleration Gxhat, and means for modifying said control amount according to the level of road disturbance.

12. A device according to claim 11, wherein said control amount modifying means is adapted to modify said control amount by modifying said final estimation quantity according to the level of road disturbance.

13. A device according to claim 11, wherein said turn behavior control means is adapted to control the turn behavior of the vehicle according to said control amount based upon said final estimation quantity when said final estimation quantity exceeds a threshold value, and said control amount modifying means is adapted to modify said control amount by modifying said threshold value according to the level of road surface disturbance.

14. A device for controlling behavior of a vehicle, comprising means for detecting lateral acceleration Gy, means for detecting actual yaw rate r of the vehicle body, means for calculating an estimation quantity expressing lateral sliding of the vehicle based upon the lateral acceleration Gy and the detected actual yaw rate r, means for presuming spin of the vehicle body based upon at least said estimation quantity, and means for controlling spin of the vehicle so as to decrease the spin based upon the presumed spin, further comprising means for detecting vehicle speed V, means for detecting steering angle θ

, means for calculating target yaw rate rt from the steering angle θ and

the vehicle speed V, means for calculating target lateral acceleration Gyt from the steering angle θ and

the vehicle speed V, means for judging if the deviation between the target yaw rate rt and the detected actual yaw rate r or the deviation between the target lateral acceleration Gyt and the lateral acceleration Gy is not greater than a predetermined threshold value, and means for prohibiting the behavior control by said behavior control means when said deviation with respect to yaw rate or said deviation with respect to lateral acceleration is not greater than said threshold value.

15. A device for controlling behavior of a vehicle, comprising means for detecting lateral acceleration Gy, means for detecting actual yaw rate r of the vehicle body, means for calculating an estimation quantity expressing lateral sliding of the vehicle based upon the lateral acceleration Gy and the detected actual yaw rate r, means for presuming spin of the vehicle based upon at least said estimation quantity, and means for controlling spin of the vehicle so as to decrease the spin based upon the presumed spin, further comprising means for judging a first condition that the vehicle is braked during turn, means for judging a second condition that the vehicle is accelerated in an under-steer condition, and means for expediting the behavior control by the behavior control means when said first condition or said second condition is detected.