Method, medium, and apparatus for docking mobile robot

• US 8,255,084 B2
• Filed: 05/21/2008
• Issued: 08/28/2012
• Est. Priority Date: 01/04/2008
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Myeong, Hyeon, Jeong, Woo-yeon, Lee, Su-jin
• Primary Examiner(s): Black, Thomas G.
• Assistant Examiner(s): Olsen, Lin B
• Application Number:
  US12/153,601
• Publication Number:
  US 20090177320A1
• Time in Patent Office: 1,560 Days
• Field of Search: 318/568.17, 701/24
• US Class Current: 700/258
• CPC Class Codes: B25J 19/005 using batteries, e.g. as a back-up power source
• CPC Class Codes: B25J 5/00 Manipulators mounted on wheels or on carriages B25J1/00 takes precedence; programme-controlled manipulators B25J9/00 ; vehicle aspects B60, B62, e.g. remote-controlled steering for motor vehicles B62D1/24; control of position of vehicles G05D1/00
• CPC Class Codes: G05D 1/0225 involving docking at a fixed facility, e.g. base station or loading bay parking aids B62D15/027
• CPC Class Codes: G05D 1/0242 using non-visible light signals, e.g. IR or UV signals

Abstract

Provided are a method, medium, and apparatus for docking a mobile robot. The method includes: (a) receiving a docking signal, which is transmitted from a signal transmitting unit, by using a signal receiving unit loaded in the mobile robot while the mobile robot is moving; (b) estimating a range of poses of the signal transmitting unit based on the received docking signal; (c) updating estimated poses of the signal transmitting unit by reflecting the estimated range of poses in a pose estimation algorithm when the pose of the signal transmitting unit, which was estimated using the pose estimation algorithm, exists within the estimated range of poses and adding a new pose of the signal transmitting unit, which is to be estimated using the pose estimation algorithm by reflecting the estimated range of poses, when the pose of the signal transmitting unit, which was estimated using the pose estimation algorithm, does not exist within the estimated range of poses; and (d) attempting to return the mobile robot to a charging station by using a plurality of poses of the signal transmitting unit, which were estimated by repeating operations (a) through (c) and using the pose estimation algorithm, in order of accuracy, until the mobile robot is docked in the charging station.

Claims

1. A method of docking a mobile robot, the method comprising:

(a) receiving a docking signal, which is transmitted from a signal transmitting unit, by using a signal receiving unit loaded in the mobile robot while the mobile robot is moving;

(b) estimating a range of poses of the signal transmitting unit based on the received docking signal;

(c) updating estimated poses of the signal transmitting unit by reflecting the estimated range of poses in a pose estimation algorithm when a pose of the signal transmitting unit, which was estimated using the pose estimation algorithm, exists within the estimated range of poses and adding a new pose of the signal transmitting unit, which is to be estimated using the pose estimation algorithm by reflecting the estimated range of poses, when the pose of the signal transmitting unit, which was estimated using the pose estimation algorithm, does not exist within the estimated range of poses; and

(d) attempting to return the mobile robot to a charging station by using a plurality of poses of the signal transmitting unit, which were estimated by repeating operations (a) through (c) and using the pose estimation algorithm, in order of accuracy, until the mobile robot is docked in the charging station.

2. The method of claim 1, wherein the signal transmitting unit transmits the docking signal from the charging station of the mobile robot.

3. The method of claim 1, wherein pose of the signal transmitting unit is the position of the signal transmitting unit and a direction angle at which the signal transmitting unit transmits the docking signal.

4. The method of claim 3, wherein range of positions of the signal transmitting unit is estimated based on pose of the mobile robot, transmitting distance of the docking signal, and range of angles at which the signal receiving unit can receive the docking signal.

5. The method of claim 3, wherein range of direction angles at which the signal transmitting unit transmits the docking signal is estimated based on direction angle of the mobile robot, range of angles at which the signal receiving unit can receive the docking signal, and range of angles at which the signal transmitting unit transmits the docking signal.

6. The method of claim 1, wherein the pose estimation algorithm is a Kalman filter.

7. The method of claim 1, wherein the accuracy of pose of the signal transmitting unit is increased as the number of times that the pose of the signal transmitting unit is updated increases.

8. The method of claim 1, wherein the accuracy of a pose of the signal transmitting unit is increased when the pose of the signal transmitting unit is estimated based on a docking signal whose intensity was lower when received by the signal receiving unit.

9. The method of claim 1, wherein the accuracy of pose of the signal transmitting unit is increased as the number of times that the pose of the signal transmitting unit has recently been updated increases.

10. The method of claim 1, wherein the docking signal transmitted from the signal transmitting unit is an infrared signal.

11. An apparatus for docking a mobile robot, the apparatus comprising:

a signal transmitting unit to transmit a docking signal;

a signal receiving unit which is loaded in a mobile robot and which receives the docking signal while the mobile robot is moving;

a pose range estimating unit to estimate a range of poses of the signal transmitting unit based on the received docking signal;

a determination unit to determine whether a pose of the signal transmitting unit, which was estimated using a pose estimation algorithm, exists within the estimated range of poses;

a pose adding/updating unit to update estimated poses of the signal transmitting unit by reflecting the estimated range of poses in the pose estimation algorithm based on the determination result of the determination unit or adding a new pose of the signal transmitting unit, which is to be estimated using the pose estimation algorithm by reflecting the estimated range of poses; and

a docking control unit which attempts to return the mobile robot to a charging station by using a plurality of poses of the signal transmitting unit, which were estimated by the pose adding/updating unit, in order of accuracy, until the mobile robot is docked in the charging station.

12. The apparatus of claim 11, wherein when the determination unit determines that pose of the signal transmitting unit, which was estimated using the pose estimation algorithm, exists within the estimated range of poses, the pose adding/updating unit updates the estimated pose of the signal transmitting unit, and when the determination unit determines that the estimated pose of the signal transmitting unit does not exist within the estimated range of poses, the pose adding/updating unit adds a new pose of the signal transmitting unit.

13. The apparatus of claim 11, wherein the signal transmitting unit transmits the docking signal from the charging station of the mobile robot.

14. The apparatus of claim 11, wherein pose of the signal transmitting unit is the position of the signal transmitting unit and a direction angle at which the signal transmitting unit transmits the docking signal.

15. The apparatus of claim 14, wherein the pose range estimating unit estimates range of positions of the signal transmitting unit based on pose of the mobile robot, transmitting distance of the docking signal, and range of angles at which the signal receiving unit can receive the docking signal.

16. The apparatus of claim 14, wherein the pose range estimating unit estimates range of direction angles, at which the signal transmitting unit transmits the docking signal, based on direction angle of the mobile robot, range of angles at which the signal receiving unit can receive the docking signal, and range of angles at which the signal transmitting unit transmits the docking signal.

17. The apparatus of claim 11, wherein the pose estimation algorithm is a Kalman filter.

18. The apparatus of claim 11, wherein the accuracy of pose of the signal transmitting unit is increased as the number of times that the pose of the signal transmitting unit is updated by the pose adding/updating unit increases.

19. The apparatus of claim 11, wherein the accuracy of pose of the signal transmitting unit is increased when the pose of the signal transmitting unit is estimated based on the docking signal whose intensity was lower when received by the signal receiving unit.

20. The apparatus of claim 11, wherein the accuracy of pose of the signal transmitting unit is increased as the number of times that the pose of the signal transmitting unit has recently been updated by the pose adding/updating unit increases.

21. The apparatus of claim 11, wherein the docking signal transmitted from the signal transmitting unit is an infrared signal.