Robot vacuum with internal mapping system

• US 7,805,220 B2
• Filed: 03/11/2004
• Issued: 09/28/2010
• Est. Priority Date: 03/14/2003
• Status: Expired due to Fees

• Current Assignee: Sharper Image Acquisition, LLC (ThreeSixty Group Ltd.)
• Original Assignee: Sharper Image Acquisition, LLC (ThreeSixty Group Ltd.)
• Inventors: Ng, Eric, Heninger, Andrew, Blair, Eric C., Parker, Andrew J., Taylor, Charles E., Lau, Shek Fai
• Primary Examiner(s): Black; Thomas G
• Assistant Examiner(s): Behncke; Christine M
• Application Number:
  US10/798,732
• Publication Number:
  US 20050000543A1
• Time in Patent Office: 2,392 Days
• Field of Search: 701/25, 701/23, 701/26, 134/18, 700/245, 700/253, 318/568.12, 318/568.17
• US Class Current: 700/253
• CPC Class Codes: G05D 1/0219 ensuring the processing of the whole working surface
• CPC Class Codes: G05D 1/0227 using mechanical sensing means, e.g. for sensing treated area
• CPC Class Codes: G05D 1/0246 using a video camera in combination with image processing means
• 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 1/027 comprising intertial navigation means, e.g. azimuth detector inertial navigation G01C21/16; inertial navigation combined with non-inertial navigation instruments G01C21/165
• 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: G05D 1/0274 using mapping information stored in a memory device navigation using map-matching G01C21/30

Abstract

A robot cleaner is described that cleans a room using a serpentine room clean and a serpentine localized clean. Sensors can include an object following sensor, a stairway detector and bumper sensors.

Claims

1. A method of operating a robot cleaner comprising:

(a) generating an internal map of an area comprising a plurality of subgrids, each subgrid comprising a plurality of cells;

(b) generating a subgrid map for each subgrid of the internal map, wherein the subgrid map has a higher resolution than resolution of the internal map;

(c) causing the robot cleaner to travel on a surface along a travel path from one subgrid to another subgrid in a spiral;

(d) during the traveling in each subgrid;

(i) gathering data corresponding to each traveled cell and each non-traveled cell of the subgrid;

(ii) at least partially cleaning the traveled cells of the subgrid; and

(iii) storing status data for each cell in the subgrid map;

(e) determining which part of the subgrid map has a highest density of uncleaned cells;

(f) using the subgrid map to calculate a travel path to the part of the subgrid that has a highest density of uncleaned cells;

(g) using the subgrid map to determine if the travel path is free from obstructions; and

(h) if path is obstructed, rotating the travel path by a predetermined number of degrees and repeating steps (f)-(g); and

(i) if path is not obstructed, repeating steps (c)-(h).

2. The method of claim 1, wherein each subgrid is cleaned in a serpentine clean.

3. The method of claim 1, wherein generating an internal map comprises generating the internal map using dead reckoning.

4. The method of claim 1,wherein wherein status data includes at least cleaned, uncleaned or obstruction.

5. The method of claim 1, wherein a width of a cell corresponds to portion of effective cleaning unit width of the robot cleaner.

6. The method of claim 1, wherein a cell can be set cleaned with a single straight line path segment of robot cleaner.

7. The method of claim 1, wherein the internal map is a room map.

8. The method of claim 1, wherein generating an internal map comprises selecting subgrid sizes and generating a subgrid map comprises selecting cell sizes.

9. The method of claim 1, wherein information in the subgrid map is cleared after the subgrid is cleaned.

10. The method of claim 1, wherein a new subgrid map is prepared for a next subgrid being cleaned.

11. A robot cleaner comprising:

a body including a cleaning unit;

at least one wheel coupled to the body;

at least one motor operatively coupled to the at least one wheel;

at least one processor operatively coupled to the at least one motor;

at least one input device operatively coupled to the at least one processor;

at least one sensor operatively coupled to the at least one processor; and

at least one memory device storing a plurality of instructions which are executable by the at least one processor to;

(a) generate an internal map of an area comprising a plurality of subgrids, each subgrid comprising a plurality of cells;

(b) generate a subgrid map for each subgrid of the internal map, wherein the subgrid map has a higher resolution than resolution of the internal map;

,

(c) cause the at least one wheel to move thereby causing the body to travel on a surface along a travel path from one subgrid to another subgrid in a spiral;

(d) during the traveling in each subgrid;

(i) gather data corresponding to each traveled cell and each non-traveled cell of the subgrid;

(ii) at least partially clean the traveled cells of the subgrid; and

(iii) store status data for each cell in the subgrid map;

(e) determine which part of the subgrid map has a highest density of uncleaned cells;

(f) use the subgrid map to calculate a travel path to the part of the subgrid map that has a highest density of uncleaned cells;

(g) use the subgrid map to determine if the travel path is free from obstructions; and

(h) if a path is obstructed, rotate the travel path by a predetermined number of degrees and repeating steps (f)-(g); and

(i) if a path is not obstructed, repeat steps (c)-(h).

12. The robot cleaner of claim 11, wherein each subgrid is cleaned in a serpentine clean.

13. The robot cleaner of claim 11, wherein generating an internal map comprises generating the internal map using dead reckoning.

14. The robot cleaner of claim 11, wherein status data includes at least cleaned, uncleaned or obstruction.

15. The robot cleaner of claim 11, wherein a width of a cell corresponds to a portion of effective cleaning unit width of the robot cleaner.

16. The robot cleaner of claim 11, wherein a cell can be set cleaned with a single straight line path segment of the robot cleaner.

17. The robot cleaner of claim 11, wherein the internal map is a room map.

18. The robot cleaner of claim 11, wherein generating an internal map comprises selecting subgrid sizes and generating a subgrid map comprises selecting cell sizes.

19. The robot cleaner of claim 11, wherein information in the subgrid map is cleared after the subgrid is cleaned.

20. The robot cleaner of claim 11, wherein a new subgrid map is prepared for a next subgrid being cleaned.