Docking assistant

• US 7,336,805 B2
• Filed: 06/16/2005
• Issued: 02/26/2008
• Est. Priority Date: 06/16/2004
• Status: Active Grant

• Current Assignee: Intellectual Ventures II LLC (Intellectual Ventures LLC)
• Original Assignee: Daimler Chrysler Company LLC (Stellantis NV)
• Inventors: Schwarzhaupt, Andreas, Spiegelberg, Gernot, Sulzmann, Armin, Gehring, Ottmar, Heilmann, Harro, Holzmann, Frederic
• Primary Examiner(s): Mehta, Bhavesh M
• Assistant Examiner(s): Seth, Manav
• Application Number:
  US11/154,772
• Publication Number:
  US 20050281436A1
• Time in Patent Office: 985 Days
• Field of Search: 382/103, 382/104, 382/113, 382/173, 382/181, 382/199, 382/203, 382/291, 340/932.2, 340/933, 340/935, 340/937, 340/958, 34099525-99528, 348/113, 348/116, 348118-120, 348148-149, 701/1, 701 23- 28, 701207-212, 701300-302
• US Class Current: 382/104
• CPC Class Codes: G06V 10/255 Detecting or recognising potential candidate objects based on visual cues, e.g. shapes

Abstract

Many day-to-day driving situations require that an operator of a motor vehicle guide the motor vehicle along a specific course and bring the vehicle to a stop at a specific location, for example in a parking bay or at a loading platform. To assist a vehicle operator in such situations, a method and a suitable device for implementing this method, include detecting the potential target objects in the image data of an image sensor and identifying the potential target objects as potential destinations in a multi-stage exclusionary method, whereupon a trajectory describing an optimized travel path is computed at least in relation to the most proximate destination. By using the multi-stage exclusionary method according to the present invention, it is possible to reliably identify potential destinations in complex image scenarios solely on the basis of their geometric form, even when the destinations have not been encoded by specific symbols.

Claims

1. A method for assisting guidance of a motor vehicle on the basis of image data, the method comprising:

acquired image data using an imaging sensor from a surrounding field of the motor vehicle;

extracting from the acquired image data positional parameters of at least one potential destination relative to the motor vehicle; and

calculating at least one trajectory describing an optimized travel path using the positional parameters so as to assist a subsequent vehicle guidance for at least one of the potential destinations,

wherein the extracting includes;

performing an edge detection and edge segmentation on the image data so as to break down the image data into a plurality of edge segments and storing interrelationships of the plurality of edge segments in a mathematical tree structure;

analyzing the plurality of edge segments for the presence of a geometric object associated with a geometrical form that may at least partially describe a potential destination so as to identify one or more potential geometric objects;

analyzing the one or more potential geometric objects for plausibility using a matching algorithm so as to identify one or more plausible objects;

performing an additional acceptance analysis so as to identify at least one accepted object, the additional acceptance analysis including analyzing a shape of the image formation of each object in the image data based on knowledge of at least one imaging property of the imaging sensor relative to the surrounding field; and

storing at least one accepted object that corresponds to a most proximate destination together with corresponding relative positional data in an object list.

2. The method as recited in claim 1, further comprising processing the mathematical tree structure using a tree traversal algorithm.

3. The method as recited in claim 1, wherein the potential geometric objects include at least one of rectangles and squares.

4. The method as recited in claim 1, wherein the matching algorithm includes an IPC algorithm.

5. The method as recited in claim 1, wherein, when the image sensor is disposed in an elevated position an image of a rectangular or square potential destination is formed as a trapezoid in the image data, and the acceptance analysis rejects as potential destinations those objects that do not exhibit a distorted image a typical geometric shape.

6. The method as recited in claim 1, wherein the calculation of the at least one trajectory includes considering a steering property and a capability of the motor vehicle.

7. The method as recited in claim 6, further comprising rejecting a potential destination that is not reachable given the steering property and capability of the motor vehicle.

8. The method as recited in claim 1, further comprising informing a driver of the motor vehicle about a position of at least one potential destination and about the at least one trajectory.

9. The method as recited in claim 1, further comprising performing an at least semi-automatic vehicle guidance to the most proximate destination using the at least one trajectory.

10. The method as recited in claim 9, further comprising using at least one of an audible and a visual signaling during the vehicle guidance to assist a driver of the vehicle in observing the trajectory.

11. The method as recited in claim 9, further comprising:

continuously monitoring a position of the stored at least one accepted object during the vehicle guidance;

selecting a new most proximate destination went the most proximate destination is no longer easily reachable, wherein the new most proximate destination is selected based on an active position of the motor vehicle and in determining the at least one accepted object that is best reachable, considering a steering properties and a capability of the vehicle; and

computing a new trajectory describing a new optimized travel path based on the active position.

12. The method as recited in claim 1, wherein the motor vehicle is a truck and wherein the surrounding field includes a docking station.

13. A device for assisting guidance of a motor vehicle using image data, the device comprising:

an imaging sensor configured to acquire image data from a field surrounding the motor vehicle;

an image-processing unit configured to extract positional parameters of at least one potential destination relative to the motor vehicle from the image data;

a processing unit configured to compute at least one trajectory describing an optimized travel path to a potential designation; and

a vehicle guidance system configured to assist in guiding the vehicle to the potential destination,

wherein the image-processing unit includes;

an edge detector and segmenter for extracting relative positional parameters of the at least one potential destination from the image data;

a locating unit disposed downstream from the image processing unit and configured to locate corresponding objects in the image data having geometric shapes corresponding at least partially to the at least potential destination;

a memory unit for storing object patterns;

a comparator unit configured to analyze the corresponding geometric objects, to check for plausibility using a matching algorithm for comparing the object patterns stored in the memory unit;

a data memory storing the geometric object detected in the image data corresponding to the most proximate destination is stored, along with the corresponding relative positional data, in an object list;

an acceptance analysis unit configured to analyze a shape of an image formation of the objects in the image data based on the knowledge of the imaging properties of the imaging sensor in relation to its surrounding field, to communicate with the data memory, and to transfer the most proximate destination to the processing unit.

14. The device as recited in claim 13, wherein the imaging sensor includes at least one of a camera, a laser scanner and a millimeter wave radar.

15. The device as recited in claim 13, wherein the imaging sensor is disposed at an elevated position on the vehicle from where the imaging sensor to observe a part of the field surrounding the motor vehicle relevant to the driving task.

16. The device as recited in claim 15, wherein the imaging sensor is mounted in such a way that an image of at least one portion of the motor vehicle is included in the image data.

17. The device as recited in claim 13, wherein the vehicle guidance system communicates with at least one of a steering, an acceleration and a braking equipment of the motor vehicle so as to be able to act on the equipment at least semi-autonomously.

18. The device as recited in claim 13, wherein the vehicle guidance system includes at least one of a visual and an audible output for communicating with a driver of the motor vehicle.

19. The device as recited in claim 13, wherein the motor vehicle is a truck and the surrounding field includes a docking station.