Mobile robot and operating method thereof

• US 9,339,163 B2
• Filed: 10/31/2014
• Issued: 05/17/2016
• Est. Priority Date: 10/31/2013
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Noh, Dongki, Baek, Seungmin
• Primary Examiner(s): Butler, Rodney
• Assistant Examiner(s): Mazzara, Anne
• Application Number:
  US14/529,742
• Publication Number:
  US 20150157182A1
• Time in Patent Office: 564 Days
• Field of Search: 701/28
• US Class Current: 1/1
• CPC Class Codes: A47L 11/4011 Regulation of the cleaning machine by electric means; Control systems and remote control systems therefor
• CPC Class Codes: A47L 11/4061 Steering means; Means for avoiding obstacles; Details related to the place where the driver is accommodated
• CPC Class Codes: G05D 1/0231 using optical position detecting means position-fixing by using electromagnetic waves other than radio waves, e.g. optical position detecting means G01S5/16
• CPC Class Codes: G05D 1/0248 in combination with a laser lasers per se H01S
• CPC Class Codes: G05D 1/0274 using mapping information stored in a memory device navigation using map-matching G01C21/30

Abstract

Data within a designated distance from a main body of the mobile robot is accumulated and stored to form a local area map. A traveling direction or a rotating direction is set while avoiding an obstacle around the main body and a path may be readily set. Repetition of unnecessary operation is prevented and thus a traveling velocity based on rapid movement may be improved. Obstacles are readily avoided and cleaning efficiency may be improved.

Claims

1. A mobile robot comprising:

a mobile main body;

an optical pattern sensor configured to sense obstacles around the main body;

a suction motor configured to suck in foreign substances around the main body during traveling;

a controller configured to extract information of the obstacles by analyzing data input from the optical pattern sensor, to set at least one of a traveling direction or a traveling path so as to avoid the obstacles, and to control the main body so as to travel to a destination while avoiding the obstacles; and

a motorized wheel configured to move the main body according to control instructions from the controller, wherein the controller includes;

an obstacle information acquisition unit configured to judge the obstacles and to calculate the positions of the obstacles from data from the optical pattern sensor; and

a map generation unit configured to generate a plurality of local area maps, each map including information of obstacles located within a designated distance from the main body, based on the information of the obstacles calculated by the obstacle information acquisition unit,

wherein when the main body moves from a first area of a first local area map to a second area of a second local area map, the map generation unit generates the second local area map by retaining data regarding a common area from the first local area map prior to movement and the second local area map after movement, adding new data after movement, and deleting data prior to movement.

2. The mobile robot according to claim 1, wherein the map generation unit generates the plurality of local area maps including information located within a designated distance from the main body in forward, backward, leftward, and rightward directions.

3. The mobile robot according to claim 1, wherein the map generation unit generates the plurality of local area maps with respect to an area of a lateral distance of 1 m and a longitudinal distance of 1 m based on information located within a distance of 50 cm in respective forward and backward directions and a distance of 50 cm in respective leftward and rightward directions.

4. The mobile robot according to claim 1, wherein the controller controls the motorized wheel so that the main body is rotated while avoiding the obstacles within a local area map with reference to a local area map during change of the traveling direction or rotation of the main body.

5. The mobile robot according to claim 1, wherein the controller sets a position of the main body prior to movement as an initial position of 0 and controls the motorized wheel so that the main body is rotated one time in place and then starts to travel.

6. The mobile robot according to claim 5, wherein when the initial position of the main body is set, the map generation unit generates at least one of the local area maps based on data input from the optical pattern sensor while the main body is rotated one time.

7. The mobile robot according to claim 1, wherein the controller further includes:

a pattern extraction unit configured to extract a pattern from the data from the optical pattern sensor and to supply the extracted pattern to the obstacle information acquisition unit; and

a position recognition unit configured to calculate a position of the main body.

8. The mobile robot according to claim 1, wherein the optical pattern sensor includes a pattern irradiation unit emitting a cross-shaped optical pattern, including a horizontal line optical pattern and a vertical line optical pattern orthogonally intersecting the horizontal line optical pattern, to a region around the main body.

9. An operating method of a mobile robot comprising:

sensing an environment around a main body of the mobile robot through an optical pattern sensor when an operation mode is set;

generating a plurality of local area maps, each map including information of obstacles located within a designated distance from the main body based on data input from the optical pattern sensor, wherein the plurality of local area maps includes first and second local area maps;

generating the second local area map according to data input from the optical pattern sensor during traveling from a first area of the first local area map to a second area of the second local area map according to the operation mode; and

controlling the main body to change a traveling direction so as to avoid an obstacle around the main body based on at least one of the local area maps when the obstacle is sensed,

wherein the second local area map is generated by retaining data regarding a common area from the first local area map prior to traveling and the second local area map after traveling, adding new data after traveling, and deleting data prior to traveling.

10. The operating method according to claim 9, further including setting a current position of the main body prior to movement as an initial position of 0, when the operation mode is set.

11. The operating method according to claim 10, further including:

rotating the main body one time at the initial position prior to movement, when the operation mode is set; and

generating at least one of the local area maps based on data input from the optical pattern sensor while the main body is rotated one time.

12. The operating method according to claim 9, wherein, when the obstacle is sensed, the main body travels so as to avoid the obstacle and simultaneously to avoid other obstacles around the main body based on obstacle information included in at least one of the local area maps.