Adaptive steering control for a motor vehicle

• US 8,121,760 B2
• Filed: 04/02/2009
• Issued: 02/21/2012
• Est. Priority Date: 04/02/2008
• Status: Expired due to Fees

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Ghoneim, Youssef, Held, Veit
• Primary Examiner(s): Chen, Shelley
• Application Number:
  US12/417,271
• Publication Number:
  US 20090254253A1
• Time in Patent Office: 1,055 Days
• Field of Search: 701/42
• US Class Current: 701/42
• CPC Class Codes: B62D 5/008 Changing the transfer ratio between the steering wheel and the steering gear by variable supply of energy, e.g. by using a superposition gear
• CPC Class Codes: B62D 5/0463 calculating assisting torque from the motor based on driver input
• CPC Class Codes: B62D 6/002 computing target steering angles for front or rear wheels B62D7/159 takes precedence
• CPC Class Codes: B62D 6/008 Control of feed-back to the steering input member, e.g. simulating road feel in steer-by-wire applications
• CPC Class Codes: B62D 6/02 responsive only to vehicle speed

Abstract

An adaptive steering control system is provided for a motor vehicle. The system includes, but is not limited to a sensor for detecting a current value of an operation quantity of a steering wheel, an actor for turning steered wheels and a controller for selecting, according to the speed of the vehicle, a map (g1, g2) assigning to a detected current value of the operation quantity a setpoint value of the operation quantity for the actor, and for issuing a setpoint signal to the actor. The controller is adapted to decide whether the vehicle is in a state of motion requiring a high level of attention from the driver or not, to inhibit a switchover of the map (g1, g2) while the vehicle is in the high attention-requiring state, and to allow such a switchover while the vehicle is not in the high attention-requiring state.

Claims

1. An adaptive steering control system for a motor vehicle, comprising:

a sensor adapted to detect a current value of an operation quantity of a steering wheel;

an actor adapted to turn steered wheels; and

a controller adapted to select, according to a speed of the motor vehicle, a map assigning to a detected current value of the operation quantity, a setpoint value of the operation quantity for the actor, and for issuing a setpoint signal to the actor,

wherein the controller further is adapted to decide whether the motor vehicle is in a state of motion requiring a high level of attention from a driver and to inhibit a switchover of the map (g1, g2) while the motor vehicle is in a high attention-requiring state.

2. The adaptive steering control system of claim 1, wherein the operation quantity is a turning angle of the steering wheel and of a steered wheel.

3. The adaptive steering control system of claim 1, wherein the operation quantity is a torque applied to the steering wheel and to a steered wheel.

4. The adaptive steering control system of claim 1, wherein a linear term of a map (g1) is selected at a low vehicle speed is greater than the linear term of a map s elected at a high vehicle speed.

5. The adaptive steering control system of claim 1, wherein the controller is adapted to decide whether the motor vehicle is in the high attention-requiring state if the lateral acceleration exceeds a predetermined threshold.

6. The adaptive steering control system of claim 5, wherein the controller is connected to a lateral acceleration sensor.

7. The adaptive steering control system of claim 5, wherein the controller is connected to a steering wheel angle sensor and is adapted to estimate a lateral acceleration from a steering wheel angle detected by said sensor and a vehicle longitudinal speed.

8. The adaptive steering control system of claim 1, wherein the controller is connected to a yaw rate sensor and is adapted to decide that the motor vehicle is in the high attention-requiring state if a yaw rate exceeds a predetermined threshold.

9. The adaptive steering control system of claim 1, wherein the controller is adapted to estimate a side-slip rate of the motor vehicle and to decide that the motor vehicle is in the high attention-requiring state if the side-slip rate exceeds a predetermined threshold.

10. The adaptive steering control system of claim 7, wherein the controller is adapted to estimate a side-slip rate from a yaw rate measured by a yaw rate sensor and the lateral acceleration measured by a lateral acceleration sensor.

11. The adaptive steering control system of claim 1, wherein the controller is connected to a longitudinal acceleration sensor and is adapted to decide that the motor vehicle is in the high attention-requiring state if the longitudinal acceleration exceeds a predetermined threshold.

12. The adaptive steering control system of claim 1, wherein the controller is connected to a steering wheel angle sensor and is adapted to decide that the motor vehicle is in the high attention-requiring state if the steering wheel angular velocity exceeds a predetermined threshold.

13. The adaptive steering control system of claim 1, wherein the controller is adapted to determine a time derivative of a yaw rate and to determine that the motor vehicle is in the high attention-requiring state if a time derivative exceeds a predetermined threshold.

14. A steering control method for a motor vehicle, comprising the steps of:

detecting a current value of an operation quantity of a steering wheel;

selecting a map assigning to a detected current value of the operation quantity a setpoint value of the operation quantity;

issuing a setpoint signal to an actor of steered wheels, comprising the steps of;

deciding whether the motor vehicle is in a state of motion requiring a high level of attention from a driver;

if it is decided that the motor vehicle is not in a high attention-requiring state, selecting the map based on a speed of the motor; and

if it is decided that the motor vehicle is in a high attention-requiring state, re-selecting the map selected in a previous iteration of selecting the map based on the speed of the motor vehicle.

15. A non-transitory computer readable medium embodying a program product, said program product comprising:

an adaptive steering control program for a motor vehicle, the adaptive steering control program for the motor vehicle configured to;

detecting a current value of an operation quantity of a steering wheel;

selecting a map assigning to a detected current value of the operation quantity a setpoint value of the operation quantity;

issuing a setpoint signal to an actor of steered wheels, comprising the steps of;

deciding whether the motor vehicle is in a state of motion requiring a high level of attention from a driver;

if it is decided that the motor vehicle is not in a high attention-requiring state, selecting the map based on a speed of the motor vehicle; and

if it is decided that the motor vehicle is in a high attention-requiring state, re-selecting the map selected in a previous iteration of selecting the map based on the speed of the motor vehicle.