Method for steering a vehicle that is to be backed into a parking space

• US 7,469,765 B2
• Filed: 06/03/2005
• Issued: 12/30/2008
• Est. Priority Date: 12/05/2002
• Status: Active Grant

• Current Assignee: Bayerische Motoren Werke AG
• Original Assignee: Bayerische Motoren Werke AG
• Inventors: Pruckner, Alfred, Meitinger, Karl-Heinz, Spannheimer, Helmut
• Primary Examiner(s): Silbermann; Joanne
• Assistant Examiner(s): YEAGLEY, DANIEL S
• Application Number:
  US11/143,459
• Publication Number:
  US 20050236201A1
• Time in Patent Office: 1,306 Days
• Field of Search: 180/204, 701/28, 701/36, 701/41, 240/932.2
• US Class Current: 180/204
• CPC Class Codes: B60T 2201/10 Automatic or semi-automatic parking aid systems
• CPC Class Codes: B62D 15/0285 Parking performed automatically

Abstract

A method is provided for steering a vehicle that is to be backed into a parking space. Starting from an initial position outside the parking space, a reverse trajectory that is to be traveled to attain the parked position is determined. The vehicle reverses through five curve sections, and steering of the vehicle during the reversing procedure is controlled by an electronic control system in accordance with the reverse trajectory. When viewed from the driving direction, the second curve section represents a clothoid section, the third represents an arc section, the fourth represents an additional clothoid section and the fifth represents an additional arc section. In its initial position, the vehicle is at an angle to the longitudinal direction of the parking space and the first curve section, through which the vehicle reverses and which lies between the initial position and the start of the second curve section, is represented by a different geometrical function than the second curve section.

Claims

1. A method of steering a vehicle that is to be backed into a parking space, the vehicle being successively reversed through first, second, third, fourth, and fifth curve segments starting from an initial position outside the parking space until the vehicle attains a parked position in the parking space, each segment flowing seamlessly into a next segment and, when viewed in a driving direction, the second segment representing a clothoid section, the third segment representing an arc section, the fourth segment representing an additional clothoid section, and the fifth segment representing an additional arc section, the method comprising the acts of:

starting from the initial position of the vehicle, determining an entire reverse trajectory that is to be traveled to attain the parked position; and

controlling steering of the vehicle during the reversing procedure by an electronic control system in accordance with said trajectory;

wherein in the initial position, the vehicle is at an angle to a longitudinal direction of the parking space, and further wherein the first curve segment, through which the vehicle reverses and which lies between the initial position and the start of the second curve segment, is represented by a first geometrical function different than a second geometrical function representing the second curve segment;

wherein, during the reversing operation when entering the parking space, the rearward vehicle area is monitored by spacing sensors, and the vehicle is automatically braked when an obstacle appears in the rearward vehicle area;

wherein a vehicle speed is defined by the driver during the entire parking space entering operation, and the vehicle speed defined by the driver is limited to a defined maximal speed; and

wherein the defined maximal speed is defined as a function of a steering angle change rate.

2. The method according to claim 1, wherein steering wheel angle changes, which are controlled-in on the trajectory between the initial position and the parked position, are exclusively seamless continuous steering angle changes, so that the vehicle is drivable without stopping through the entire trajectory between the initial position and the parked position.

3. The method according to claim 2, further comprising the act of:

activating the parking space entering control by the driver only when the vehicle is stopped, the momentary vehicle position and the momentary vehicle position relative to the parking space being defined as the initial position.

4. The method according to claim 2, wherein movement of the vehicle has to be started by the driver for entering the parking space.

5. The method according to claim 1, further comprising the act of:

activating the parking space entering control by the driver only when the vehicle is stopped, the momentary vehicle position and the momentary vehicle position relative to the parking space being defined as the initial position.

6. The method according to claim 5, wherein movement of the vehicle has to be started by the driver for entering the parking space.

7. The method according to claim 1, wherein movement of the vehicle has to be started by the driver for entering the parking space.

8. The method according to claim 1, wherein a steering angle determined by the electronic control system is determined relative to the reversed path and independently of the speed.

9. The method according to claim 1, wherein the vehicle is braked by the driver during, and at the end of, the parking space entering operation.

10. The method according to claim 1, wherein the first curve segment is a straight line.

11. The method according to claim 1, wherein the first curve segment is a clothoid represented by a first clothoid function different than a second clothoid function representing the second curve segment.

12. The method according to claim 1, wherein, for reaching the initial position for the reversing, the vehicle is first driven forward laterally past the parking space and, during the driving past the parking space, the parking space geometry is scanned by spacing sensors and is stored in the electronic control system.

13. The method according to claim 1, wherein a center of the rear axle of the vehicle describes the five curve segments.

14. A method of backing a vehicle into a parking space, the method comprising the acts of:

starting from an initial position of the vehicle outside the parking space, determining an entire path through which the vehicle must be reversed until the vehicle attains a parked position in the parking space;

controlling steering of the vehicle during the reversing in accordance with the path by an electronic control unit, wherein the vehicle is situated in the initial position diagonally with respect to a longitudinal direction of the parking space, said controlling act further comprising the acts of;

successively reversing the vehicle through five curve segments, each segment flowing seamlessly into the next, wherein the first curve segment lying between the initial position and a beginning of the second curve segment has a different geometrical function than the second curve segment, wherein the second curve segment is a clothoid segment,

wherein a vehicle speed is defined by the driver during the entire parking space entering operation, and the vehicle speed defined by the driver is limited to a defined maximal speed;

wherein the defined maximal speed is defined as a function of a steering angle change rate.

15. An electronic control unit for steering a vehicle that is to be backed into a parking space beginning from an initial position outside of the parking space, the control unit comprising:

a computer readable medium having stored therein program code segments that;

determine an entire path through which the reversing must take place to attain a parked position;

control steering of the vehicle during the reversing beginning from an initial position situated diagonally with respect to a longitudinal direction of the parking space, said control operating over the entire path the vehicle reverses; and

defines five curve segments through which the vehicle successively reverses in a seamless manner, a first curve segment lying between the initial position and a beginning of a second curve segment having a different geometrical function than the second curve segment,

wherein a vehicle speed is defined by the driver during the entire parking space entering operation, and the vehicle speed defined by the driver is limited to a defined maximal speed;

wherein the defined maximal speed is defined as a function of a steering angle change rate.