Driving lane tracking system

• US 6,321,159 B1
• Filed: 10/14/1999
• Issued: 11/20/2001
• Est. Priority Date: 04/20/1999
• Status: Expired due to Fees

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Horiuchi, Shinichiro, Nohtomi, Shinya
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Donnelly, Arthur D.
• Application Number:
  US09/418,967
• Time in Patent Office: 768 Days
• Field of Search: 701/207, 701/28, 701/116, 701/117, 701/118, 701/213, 701/220, 701/300, 701/96, 180/169, 340/903
• US Class Current: 701/207
• CPC Class Codes: B60G 2400/0523 Yaw rate
• CPC Class Codes: B60G 2400/104 lateral or transversal with regard to vehicle
• CPC Class Codes: B60G 2400/41 Steering angle
• CPC Class Codes: B60G 2400/824 Travel path sensing; Track monitoring
• CPC Class Codes: B60G 2401/142 Visual Display Camera, e.g. LCD
• CPC Class Codes: B60G 2800/24 Steering, cornering
• CPC Class Codes: B60T 2201/08 Lane monitoring; Lane Keeping Systems
• CPC Class Codes: B60T 2201/087 using active steering actuation
• CPC Class Codes: B60T 2201/089 using optical detection
• CPC Class Codes: B60T 2260/02 Active Steering, Steer-by-Wire
• CPC Class Codes: B62D 1/28 non-mechanical , e.g. following a line or other known markers
• CPC Class Codes: B62D 15/025 Active steering aids, e.g. helping the driver by actively influencing the steering system after environment evaluation B62D1/28 takes precedence

Abstract

Preview information is obtained by processing data from image data of a CCD camera, and it is treated as a known disturbance. Then, models for a vehicle and a target road path, typically consisting of DARMA (deterministic auto-regressive moving average) models are prepared so as to give a relationship between a front wheel steering angle command and a lateral deviation of the vehicle. An extended generalized predictive control theory is applied to these models so as to compensate for tracking errors that may arise as a result of the known disturbance. Thus, a favorable tracking capability can be achieved with a relatively simple structure, by executing a prediction control which requires only such variable that can be measured both easily and accurately.

Claims

1. A driving lane tracking system, comprising:

road path previewing means for detecting a current position of a vehicle with respect to a road path, and previewing a target road path lying a certain distance ahead of a vehicle;

a steering angle sensor for detecting a current steering angle of the vehicle;

a storage unit for storing data obtained from said road path previewing means and said steering angle sensor;

a steering actuator which at least assists a steering effort made by a vehicle operator; and

a control unit for controlling said steering actuator so as to minimize a weighted sum of a square of the lateral deviation with respect to said target road path and a square of an increment of the steering angle command value at a plurality of future points according to data on the past, current and target road path.

2. A driving lane tracking system according to claim 1, wherein said control unit incorporates a computer algorithm based on a generalized predictive control theory which treats changes in the curvature of the road path as known disturbances.

3. A driving lane tracking system according to claim 1, wherein said road path previewing means comprises an electronic camera mounted on said vehicle.

4. A driving lane tracking system according to claim 3, wherein said road path previewing means is adapted to identify the road path by detecting a line marked on a road to define a driving lane.

5. A driving lane tracking system according to claim 1, wherein said road path previewing means comprises a navigation system which can identifies a current vehicle position in relation to a map incorporated therein.

6. A driving lane tracking system according to claim 1, further comprising a radar device for detecting other objects on the road.