SYSTEMS AND METHODS FOR DRIVER INTERVENTION IN AN AUTOMATIC STEERING SYSTEM

• US 20110098890A1
• Filed: 10/22/2009
• Published: 04/28/2011
• Est. Priority Date: 10/22/2009
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust)
• Inventors: Ryu, Jihan, Lee, Yong H., Deng, Weiwen
• Granted Patent: US 8,930,079 B2
• Time in Patent Office: Days
• US Class Current: 701/42
• CPC Class Codes: B62D 1/286 Systems for interrupting non-mechanical steering due to driver intervention

Abstract

A vehicle steering system includes an automatic steering control unit configured to control the vehicle steering system when in an automatic operational state and a driver intervention unit is configured to determine driver intervention during the automatic operational state. The driver intervention unit comprising a decision software module configured to determine driver intervention.

Claims

1. A vehicle steering system, comprising:

a steering angle sensor configured to measure a steering angle;

an automatic steering control unit configured to control the vehicle steering system when in an automatic operational state; and

a driver intervention unit configured to detect driver intervention during the automatic operational state, the driver intervention unit comprising a decision software module configured to determine driver intervention as a function of the measured steering angle and a second steering angle.

2. The vehicle steering system of claim 1, wherein the automatic steering control unit is configured to control an electric power steering system.

3. The vehicle steering system of claim 1, wherein the decision software module is configured to determine driver intervention where the differential between the measured steering angle and a second steering angle exceeds a threshold.

4. The vehicle steering system of claim 1, wherein the driver intervention unit is configured to control the operational state of the vehicle steering system, the operational state including automatic operation and manual operation.

5. The vehicle steering system of claim 1, wherein the second steering angle is a calculated steering angle that is determined as a function of a model of the vehicle steering system.

6. The vehicle steering system of claim 5, wherein the model is J_e{umlaut over (θ

)}_s+B_e{dot over (θ

)}_s+K_eθ

_s=Σ

T=T_d+T_m−

T_a, where J_e is an equivalent moment of inertia of the vehicle steering system, B_e is an equivalent damping of the vehicle steering system, K_e is an equivalent stiffness of the vehicle steering system, θ

_s is the steering angle, T_d is a driver applied steering torque, T_m is an equivalent motor assist torque, and T_a is an equivalent tire alignment torque.

7. The vehicle steering system of claim 1, wherein the second steering angle is a steering angle command generated by the automatic steering control unit.

8. The vehicle steering system of claim 7, wherein the steering angle command is a function of a desired path.

9. The vehicle steering system of claim 1, the decision software module comprising a low pass filter that is configured to filter the measured steering angle.

10. A vehicle steering system, comprising:

a memory storing a hands-off moment of inertia of the vehicle steering system;

an automatic steering control unit configured to control the vehicle steering system when in an automatic operational state; and

a driver intervention unit configured to detect driver intervention during the automatic operational state, the driver intervention unit comprising a decision software module configured to determine driver intervention as a function of the hands-off moment of inertia and a calculated moment of inertia.

11. The vehicle steering system of claim 10, wherein the automatic steering control unit is configured to control an electric power steering system.

12. The vehicle steering system of claim 10, wherein the decision software module is configured to determine driver intervention where the differential between the hands-off moment of inertia and the calculated moment of inertia exceeds a threshold.

13. The vehicle steering system of claim 10, wherein the driver intervention unit is configured to control the operational state of the vehicle steering system, the operational state including automatic operation and manual operation.

14. The vehicle steering system of claim 10, wherein the calculated moment of inertia is determined as a function of a model of the vehicle steering system.

15. The vehicle steering system of claim 14, wherein the model is J_e{umlaut over (θ

)}_s+B_e{dot over (θ

)}_s+K_eθ

_s=Σ

T=T_d+T_m−

T_a, where J_e is the calculated moment of inertia of the vehicle steering system, B_e is an equivalent damping of the vehicle steering system, K_e is an equivalent stiffness of the vehicle steering system, θ

_s is a steering angle, T_d is a driver torque, T_m is an equivalent motor torque, and T_a is an equivalent tire alignment torque.

16. A vehicle steering system, comprising:

a torque sensor configured to measure driver torque applied to a steering wheel of the vehicle steering system;

an automatic steering control unit configured to control the vehicle steering system when in an automatic operational state; and

a driver intervention unit configured to detect driver intervention during the automatic operational state, the driver intervention unit comprising a decision software module configured to determine driver intervention as a function of high-frequency noise of the driver torque measured by the torque sensor.

17. The vehicle steering system of claim 16, wherein the automatic steering control unit is configured to control an electric power steering system.

18. The vehicle steering system of claim 16, the decision software module comprising a high pass filter.

19. The vehicle steering system of claim 16, wherein the decision software module is configured to determine driver intervention where the high-frequency noise exceeds a threshold.

20. The vehicle steering system of claim 16, wherein the driver intervention unit is configured to control the operational state of the vehicle steering system, the operational state including automatic operation and manual operation.