MOVING ROBOT AND METHOD TO BUILD MAP FOR THE SAME

• US 20120089295A1
• Filed: 09/19/2011
• Published: 04/12/2012
• Est. Priority Date: 10/07/2010
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: AHN, Sung Hwan, Hyung, Seung Yong, Roh, Kyung Shik, Yoon, Suk June
• Granted Patent: US 9,110,472 B2
• Time in Patent Office: Days
• US Class Current: 701/28
• CPC Class Codes: G05D 1/0242 using non-visible light signals, e.g. IR or UV signals
• CPC Class Codes: G05D 1/0274 using mapping information stored in a memory device navigation using map-matching G01C21/30

Abstract

A moving robot and a method to build a map for the same, wherein a 3D map for an ambient environment of the moving robot may be built using a Time of Flight (TOF) camera that may acquire 3D distance information in real time. The method acquires 3D distance information of an object present in a path along which the moving robot moves, accumulates the acquired 3D distance information to construct a map of a specific level and stores the map in a database, and then hierarchically matches maps stored in the database to build a 3D map for a set space. This method may quickly and accurately build a 3D map for an ambient environment of the moving robot.

Claims

1. A method to build a map for a moving robot, the method comprising:

acquiring 3D distance information of an object present in a path along which the moving robot moves;

accumulating the acquired 3D distance information to construct maps of a specific size level and storing the maps in a database; and

hierarchically matching, by a computer, the maps stored in the database to build a 3D map for a set space.

2. The method according to claim 1, wherein the accumulating the acquired 3D distance information comprises accumulating the 3D distance information based on a coordinate system of a movement start point of the moving robot while the moving robot travels a preset distance, or while the moving robot travels over a preset area, or during a preset time when the moving robot travels at a constant speed.

3. The method according to claim 1, wherein the hierarchically matching the maps to build the 3D map for the set space comprises:

determining whether or not two maps of equal size level are present in the database;

matching, upon determining that two maps of equal size level are present in the database, the two maps using an Iterative Closest Point (ICP) algorithm to build a new map of an increased size level; and

storing the new map in the database.

4. The method according to claim 3, further comprising:

determining whether or not two or more maps are present in the database upon completion of traveling of the moving robot for the set space; and

matching, upon determining that two or more maps are present in the database, said two or more maps using the ICP algorithm in an order in which said two or more maps have been generated to build a final map for the set space.

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

controlling the moving robot in accordance with the built 3D map.

6. A method to build a map for a moving robot, the method comprising:

localizing the moving robot;

acquiring 3D distance information of an object present in a path along which the moving robot moves;

accumulating the acquired 3D distance information to construct maps of a specific level and storing the maps, together with a result of the localization of the moving robot, in a database;

determining whether or not two maps of equal size level are present in the database; and

upon determining that two maps of equal level are present in the database,

executing, by a computer, an Iterative Closest Point (ICP) algorithm on said two maps,

calculating, by a computer, new rigid body transformation information by combining a result of the localization of the moving robot and a result of the execution of the ICP algorithm, and

matching, by a computer, said two maps using the calculated new rigid body transformation information to build a new map of an increased level to build a 3D map for a set space.

7. The method according to claim 6, further comprising storing the new map in the database.

8. The method according to claim 6, wherein localization of the moving robot is performed using Extended Kalman Filter (EKF)-based Simultaneous Localization And Map-building (SLAM).

9. The method according to claim 6, wherein the accumulating the acquired 3D distance information comprises accumulating the 3D distance information based on a coordinate system of a movement start point of the moving robot while the moving robot travels a preset distance, or while the moving robot travels over a preset area, or during a preset time when the moving robot travels at a constant speed.

10. The method according to claim 7, further comprising:

determining whether or not two or more maps are present in the database upon completion of traveling of the moving robot for the set space; and

matching, upon determining that two or more maps are present in the database, said two or more maps using the ICP algorithm in an order in which said two or more maps have been generated to build a final map for the set space.

11. A moving robot comprising:

a 3D distance information acquirer to acquire 3D distance information of an object present in a path along which the moving robot moves; and

a controller to accumulate the acquired 3D distance information to construct maps of a specific size level and to store the maps in a database and then to hierarchically match the maps stored in the database to build a 3D map for a set space.

12. The moving robot according to claim 11, wherein the 3D distance information acquirer is a Time of Flight (TOF) camera.

13. The moving robot according to claim 11, wherein the controller accumulates the 3D distance information based on a coordinate system of a movement start point of the moving robot while the moving robot travels a preset distance, or while the moving robot travels over a preset area, or during a preset time when the moving robot travels at a constant speed.

14. The moving robot according to claim 11, wherein the controller

determines whether or not two maps of equal size level are present in the database,

matches, upon determining that two maps of equal size level are present in the database, the two maps using an Iterative Closest Point (ICP) algorithm to build a new map of an increased level, and

stores the new map in the database.

15. The moving robot according to claim 14, wherein the controller

determines whether or not two or more maps are present in the database upon completion of traveling of the moving robot for the set space, and

matches, upon determining that two or more maps are present in the database, the two or more maps using the ICP algorithm in an order in which the two or more maps have been generated to build a final map for the set space.