Semi-autonomous parking control system for a vehicle providing tactile feedback to a vehicle operator

• US 5,742,141 A
• Filed: 06/04/1996
• Issued: 04/21/1998
• Est. Priority Date: 06/04/1996
• Status: Expired due to Fees

• Current Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Original Assignee: Ford Motor Company
• Inventors: Czekaj, James L.
• Primary Examiner(s): Cabeca, John W.
• Application Number:
  US08/658,113
• Time in Patent Office: 686 Days
• Field of Search: 180/204, 180/167, 180/199, 364/424.01, 364/449, 364/436, 364/460, 364/461, 364/424.1, 364/424.05, 364/426.01, 318/587, 318/580, 318/560, 318/581
• US Class Current: 318/587
• CPC Class Codes: B60T 2201/10 Automatic or semi-automatic parking aid systems
• CPC Class Codes: B62D 15/028 Guided parking by providing commands to the driver, e.g. acoustically or optically
• CPC Class Codes: B62D 15/0285 Parking performed automatically

Abstract

A semi-autonomous parking system calculates the current position as well as the desired trajectory required to accomplish the parking task by utilizing vehicle position measurements. The parking system alters the power steering'"'"'s required effort to maneuver the vehicle thus providing tactile feedback to the vehicle operator. The required effort is decreased when it is determined that the operator is steering the vehicle within the desired trajectory and is increased when it is determined that the operator is steering the vehicle outside the desired trajectory. The operator can feel increases and decreases in steering effort at the steering wheel.

Claims

1. A method for parking a vehicle, comprising the steps of:

engaging a semi-autonomous parking control system for providing tactile feedback;

receiving inputs from sensors and determining vehicle position, and calculating desired and actual vehicle trajectories;

comparing said trajectories and determining a trajectory error;

determining a trajectory error tolerance;

determining whether said trajectory error is decreasing;

determining whether a required steering effort to maneuver said vehicle is less than a maximum steering effort when said trajectory error exceeds said trajectory error tolerance and said trajectory error is not decreasing;

incrementing said required steering effort by a predetermined amount to increase required steering effort and thereby provide said tactile feedback when said required steering effort is less than said maximum steering effort and when said trajectory error exceeds said trajectory error tolerance and said trajectory error is not decreasing;

determining whether parking is completed after incrementing said required steering effort, and returning to step of receiving inputs when parking is not complete; and

determining whether parking is completed when said required steering effort is not less than said maximum steering effort, said trajectory error exceeds said trajectory error tolerance and said trajectory error is not decreasing, and returning to step of receiving inputs when parking is not complete.

2. The method of claim 1, including the steps of:

determining whether said required steering effort is greater than a minimum steering effort when said trajectory error does not exceed said trajectory error tolerance or when said trajectory error tolerance is decreasing;

decrementing said required steering effort by a preselected amount to decrease required steering effort and thereby provide said tactile feedback when said required steering effort is greater than said minimum steering effort and when said trajectory error does not exceed said trajectory error tolerance or said trajectory error tolerance is decreasing;

determining whether parking is completed after decrementing said required steering effort, and returning to step of receiving inputs when parking is not complete; and

determining whether parking is completed when said required steering effort is not greater than said minimum steering effort and when said trajectory error does not exceed said trajectory error tolerance or said trajectory error tolerance is decreasing, and returning to step of receiving inputs when parking is not complete.

3. The method of claim 1 wherein the step of receiving inputs and determining vehicle position includes:

determining vehicle position with respect to parked vehicles, curbs and other objects defining a parking area.

4. The method of claim 1 wherein the step of receiving inputs and determining vehicle position includes:

determining vehicle position with respect to obstacles.

5. A method for semi-autonomously parking a vehicle, comprising the steps of:

engaging a Semi-autonomous parking control system for providing tactile feedback;

applying a steering effort by an operator to a steering wheel of a power steering system to steer said vehicle to a desired parked position;

receiving inputs from sensors and producing vehicle position data;

calculating a desired vehicle trajectory to said desired parked position using said vehicle position data;

calculating an actual vehicle trajectory to said desired parked position using said vehicle position data;

comparing said trajectories and determining a trajectory error;

determining a trajectory error tolerance;

determining whether said trajectory error is decreasing;

determining whether a required steering effort to maneuver said vehicle to said parked position along said desired vehicle trajectory is less than a maximum steering effort when said trajectory error exceeds said trajectory error tolerance and said trajectory error is not decreasing;

incrementing said required steering effort by a predetermined amount to increase operator steering effort and thereby provide said tactile feedback when said required steering effort is less than said maximum steering effort;

determining whether parking is completed after incrementing said required steering effort, and returning to step of receiving inputs when parking is not complete;

determining whether parking is completed when said required steering effort is not less than said maximum steering effort, and returning to step of receiving inputs when parking is not complete; and

disengaging said parking control system when parking is completed.

6. The method of claim 5, including the steps of:

determining whether said required steering effort to maneuver said vehicle to said parked position along said desired vehicle trajectory is greater than a minimum steering effort when said trajectory error does not exceed said trajectory error tolerance or when said trajectory error tolerance is decreasing;

decrementing said required steering effort by a preselected amount to decrease operator steering effort and thereby provide said tactile feedback when said required steering effort is greater than said minimum steering effort and when said trajectory error does not exceed said trajectory error tolerance or when said trajectory error tolerance is decreasing;

determining whether parking is completed after decrementing said required steering effort, and returning to step of receiving input when parking is not complete; and

determining whether parking is completed when said required steering effort is not greater than said minimum steering effort, and returning to step of receiving inputs when parking is not complete.

7. The method of claim 5 wherein the step of receiving inputs and determining vehicle position includes:

determining vehicle position with respect to parked vehicles, curbs and other objects defining a parking area.

8. The method of claim 5 wherein the step of receiving inputs and determining vehicle position includes:

determining vehicle position with respect to obstacles.

9. A semi-autonomous parking control system providing tactile feedback to an operator of a vehicle, comprising:

means for engaging and disengaging said parking control system;

means for receiving inputs from sensors, determining vehicle position, calculating desired and actual vehicle trajectories, comparing said trajectories and determining a trajectory error, determining a trajectory error tolerance, and determining whether said trajectory error is decreasing;

means for determining whether a required steering effort to maneuver said vehicle is less than a predetermined maximum steering effort;

means for incrementing said required steering effort by a predetermined amount to increase required steering effort and thereby provide said tactile feedback when said required steering effort is less than said maximum steering effort, said trajectory error exceeds said trajectory error tolerance, and said trajectory error is not decreasing; and

means for disengaging said parking system when parking is complete.

10. A parking control system, as set forth in claim 9, including:

means for decrementing said required steering effort by a preselected amount to decrease required steering effort and thereby provide said tactile feedback when said required steering effort exceeds a predetermined minimum steering effort and said trajectory error does not exceed said trajectory error tolerance, and when said required steering effort exceeds said predetermined minimum steering effort and said trajectory error tolerance is decreasing.