Location mark detecting method for robot cleaner and robot cleaner using the method

• US 7,184,586 B2
• Filed: 05/15/2003
• Issued: 02/27/2007
• Est. Priority Date: 02/07/2003
• Status: Expired due to Fees

• Current Assignee: Samsung Gwangju Electronics Co., Ltd. (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Gwangju Electronics Co., Ltd. (Samsung Electronics Co. Ltd.)
• Inventors: Song, Jeong-gon, Jeon, Kyong-hui
• Primary Examiner(s): Mancuso; Joseph
• Assistant Examiner(s): LIEW, ALEX KOK SOON
• Application Number:
  US10/439,127
• Publication Number:
  US 20040156541A1
• Time in Patent Office: 1,384 Days
• Field of Search: None
• US Class Current: 382/153
• CPC Class Codes: A47L 2201/04 Automatic control of the travelling movement; Automatic obstacle detection
• CPC Class Codes: G01S 5/16 using electromagnetic waves other than radio waves
• CPC Class Codes: G05D 1/0234 using optical markers or beacons optical beacons per se G01S1/70
• CPC Class Codes: G05D 1/0242 using non-visible light signals, e.g. IR or UV signals
• CPC Class Codes: G05D 1/0255 using acoustic signals, e.g. ultra-sonic singals sonar systems designed for anti-collision purposes G01S15/93
• CPC Class Codes: G05D 1/0272 comprising means for registering the travel distance, e.g. revolutions of wheels measuring distance traversed on the ground by vehicles, e.g. using odometers G01C22/00
• CPC Class Codes: G06T 7/73 using feature-based methods

Abstract

A location mark detecting method of a robot cleaner capable of accurately detecting location marks from an image captured by an upwardly looking camera. The location mark detecting method comprises the steps of obtaining from the image object marks to be compared with the reference location marks, determining whether shapes of the object marks are identical to those of the reference location marks, determining whether a distance separating the object marks is identical to that between the reference location marks if it is determined that the shapes are identical, determining whether a surrounding image of the object marks is identical to that of the reference location marks if it is determined that the distances are identical, and identifying the object marks as the location marks if it is determined that the surrounding images are identical. A robot cleaner capable of wirelessly communicating with an external device comprises a driving unit, an upwardly-looking camera for capturing an image of a ceiling above an area to be cleaned on which location marks are disposed, and a control unit for detecting the location marks from the image captured by the upwardly-looking camera, the control unit commanding the driving unit utilizing information of the current location to perform a work command.

Claims

1. A location mark detecting method used by a robot cleaner, which includes an upwardly-looking camera capturing an area on which location marks are disposed, a control unit recognizing a current location of the robot cleaner based on information in a single image captured by the camera and reference location marks stored in a storage, and a driving unit being driven in accordance with a signal of the control unit, in the location mark detecting method the control unit detecting the location marks from the image, the method comprising the steps of:

obtaining from the single image, first and second object marks to be compared with the stored reference location marks;

determining whether the shapes of the object marks are identical to those of the stored reference location marks;

determining whether the distance between the object marks is identical to the distance between the reference location marks if it is determined that the shapes are identical;

determining whether a surrounding image of the object marks is identical to an image surrounding that of the reference location marks if it is determined that the distances are identical; and

identifying the object marks as the location marks if it is determined that the surrounding images are identical.

2. The location mark detecting method of the robot cleaner of claim 1, wherein the location marks include two marks disposed separated from each other.

3. The location mark detecting method of the robot cleaner of claim 2, wherein one of the two marks is a first mark shaped as a black circle and the other is a second mark shaped as a black circle having the same diameter as that of the first mark or a smaller diameter than that of the first mark.

4. The location mark detecting method of the robot cleaner of claim 2, wherein one of the two marks is a first mark shaped in a black circle and the other is a second mark shaped in a black doughnut shape.

5. The location mark detecting method of claim 1, wherein the location marks are disposed on a ceiling of an area to be cleaned.

6. The location mark detecting method of claim 1, wherein the camera is disposed in a body of the robot cleaner upwardly-looking with respect to the direction of travel of the robot cleaner, so as to capture the ceiling of the area to be cleaned.

7. The location mark detecting method of claim 6, wherein the location marks include two marks disposed separated from each other.

8. The location mark detecting method of claim 7, wherein one of the two marks is a first mark shaped as a black circle and the other is a second mark shaped as a black circle having the same diameter as that of the first mark or a smaller diameter than that of the first mark.

9. The location mark detecting method of claim 7, wherein one the two marks is a first mark shaped as a black circle and the other is a second mark shaped as a black doughnut shape.

10. A robot cleaner performing an operation while wirelessly communicating with an external device, the robot cleaner comprising:

a driving unit for driving a plurality of wheels;

an upwardly-looking camera for capturing an image on a ceiling above an area to be cleaned, said ceiling being where location marks are disposed; and

a control unit for detecting the location marks from a single image captured by the upwardly looking camera by referencing shapes, distance, and images surrounding the stored reference location marks, to thereby perceive the current location of the robot cleaner, and

the control unit commands the driving unit utilizing information of the current location to perform a work command.

11. The robot cleaner of claim 10, wherein the location marks include two marks disposed separated from each other.

12. The robot cleaner of claim 11, wherein one of the two marks is a first mark shaped as a black circle and the other is a second mark shaped as a black circle having the same diameter as that of the first mark or a smaller diameter than that of the first mark.

13. The robot cleaner of claim 11, wherein one of the two marks is a first mark shaped as a black circle and the other is a second mark shaped as a black doughnut shape.