Methods and systems for complete coverage of a surface by an autonomous robot

• US 10,583,562 B2
• Filed: 03/16/2017
• Issued: 03/10/2020
• Est. Priority Date: 11/06/2009
• Status: Active Grant

• Current Assignee: iRobot Corporation
• Original Assignee: iRobot Corporation
• Inventors: Stout, Michael S., Brisson, Gabriel Francis, Di Bernardo, Enrico, Pirjanian, Paolo, Goel, Dhiraj, Case, James Philip, Dooley, Michael
• Primary Examiner(s): Moyer, Dale
• Application Number:
  US15/461,106
• Publication Number:
  US 20170197314A1
• Time in Patent Office: 1,090 Days
• 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: B25J 5/005 mounted on endless tracks or belts
• CPC Class Codes: B25J 5/007 mounted on wheels
• CPC Class Codes: B25J 9/163 learning, adaptive, model based, rule based expert control
• CPC Class Codes: B25J 9/1684 Tracking a line or surface by means of sensors
• CPC Class Codes: G05D 1/0219 ensuring the processing of the whole working surface
• CPC Class Codes: G05D 1/0234 using optical markers or beacons optical beacons per se G01S1/70
• CPC Class Codes: G05D 1/0238 using obstacle or wall sensors G05D1/0246 and G05D1/0289 take precedence; lidar systems designed for anti-collision purposes G01S17/93
• 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 1/0257 using a radar radar systems designed for anti-collision purposes between land vehicles or between land vehicle and fixed obstacles G01S13/931
• CPC Class Codes: G05D 1/0263 using magnetic strips
• 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
• CPC Class Codes: Y10S 901/01 Mobile robot
• CPC Class Codes: Y10S 901/46 Sensing device

Abstract

A robot configured to navigate a surface, the robot comprising a movement mechanism; a logical map representing data about the surface and associating locations with one or more properties observed during navigation; an initialization module configured to establish an initial pose comprising an initial location and an initial orientation; a region covering module configured to cause the robot to move so as to cover a region; an edge-following module configured to cause the robot to follow unfollowed edges; a control module configured to invoke region covering on a first region defined at least in part based at least part of the initial pose, to invoke region covering on least one additional region, to invoke edge-following, and to invoke region covering cause the mapping module to mark followed edges as followed, and cause a third region covering on regions discovered during edge-following.

Claims

1. A mobile robot configured to navigate a surface, the mobile robot comprising:

a drive operatively connected to wheels or tracks configured to move the mobile robot from an initial pose comprising a first location and a first orientation of the mobile robot on the surface to a current pose comprising a second location and a second orientation of the mobile robot on the surface;

a localizing sensor configured to obtain the current pose of the mobile robot based on localization data detected thereby; and

a control circuit configured to;

identify a restricted traversable portion of the surface;

create virtual boundaries based on the identified restricted traversable portion;

operate the drive to move the mobile robot along a path that comprises a plurality of ranks within a region of the surface, and to keep the mobile robot from accessing the identified restricted traversable portion, the region having a predefined size and location relative to the initial pose; and

detect based on the current pose that the mobile robot is proximate an end of the region of the surface based on the localization data detected by the localizing sensor or based on a next rank of the path being outside the region of the surface, and subsequently operate the drive to move the mobile robot within a different region of the surface having a predefined size and location.

2. The mobile robot of claim 1, wherein the control circuit is configured to:

establish a virtual bounding box defining the region of the surface based on the predefined size and location thereof relative to the initial pose, the virtual bounding box at least separating the identified restricted traversable portion from the region of the surface; and

operate the drive to move the mobile robot from the initial pose to the current pose along the ranks within the virtual bounding box.

3. The mobile robot of claim 2, wherein, responsive to detecting that the mobile robot is proximate the end of the region of the surface, the control circuit is configured to operate the drive to move the mobile robot to a rank of the path that is within the virtual bounding box prior to movement of the mobile robot in the different region of the surface.

4. The mobile robot of claim 2, wherein the control circuit is configured to establish the predefined size of the region of the surface before the mobile robot traverses the surface.

5. The mobile robot of claim 4, wherein the predefined size of the region of the surface comprises a static size having one or more fixed dimensions, and wherein the control circuit is configured to operate the drive to confine movement of the mobile robot in the region of the surface to be within the one or more fixed dimensions.

6. The mobile robot of claim 5, wherein at least one dimension of the one or more fixed dimensions is about 7 meters.

7. The mobile robot of claim 4, wherein the predefined size of the region of the surface comprises a dynamic size having one or more initial dimensions, and wherein the control circuit is configured to expand the one or more initial dimensions as the mobile robot traverses the surface.

8. The mobile robot of claim 2, wherein the surface corresponds to a room, and wherein the region of the surface comprises at least one dimension that extends beyond one or more dimensions of the room.

9. The mobile robot of claim 8, wherein the control circuit is configured to detect that the mobile robot is outside of the room based on the localization data detected by the localizing sensor, and operate the drive to alter an orientation of the mobile robot responsive to detection of the mobile robot outside of the room.

10. The mobile robot of claim 1, wherein the control circuit is configured to:

create a first virtual bounding box defining the region of the surface based on the predefined size and location thereof relative to the initial pose; and

create a second virtual bounding box defining the different region of the surface based on the predefined size and location thereof relative to the current pose, wherein the second virtual bounding box is different from the first virtual bounding box.

11. The mobile robot of claim 2, wherein the control circuit is configured to select a frontier between a first region of the surface that has been explored by the mobile robot and a second region of the surface that has not been explored by the mobile robot based on a calculation of an expected power consumption of the mobile robot to reach the frontier from the current pose.

12. The mobile robot of claim 2, wherein the control circuit is configured to determine that coverage of the surface is completed responsive to movement of the mobile robot within the region of the surface.

13. The mobile robot of claim 12, wherein, responsive to determination that the coverage of the surface is completed, the control circuit is configured to operate the drive to navigate the mobile robot to a charging station and/or operate an interface to output an audible or visible wireless communication to a monitoring application.

14. The mobile robot of claim 2, wherein the control circuit comprises:

a memory circuit configured to store a map comprising map parameters for the surface;

wherein the control circuit is configured to restrict analysis of the map to the region of the surface having the predefined size and location relative to the initial pose.

15. The mobile robot of claim 14, wherein, prior to movement of the mobile robot, the map parameters for the region of the surface are empty or marked as unexplored, and wherein the control circuit is configured to update the map to include locations that have been traversed and/or obstacles that have been detected as the mobile robot moves along the path.

16. A computer-implemented method for operating a mobile robot to navigate a surface, the method comprising:

identifying a restricted traversable portion of the surface;

creating virtual boundaries based on the identified restricted traversable portion;

operating, by a control circuit, a drive operatively connected to wheels or tracks, to move the mobile robot from an initial pose comprising a first location and a first orientation of the mobile robot on the surface along a path that comprises a plurality of ranks within a region of the surface, and to keep the mobile robot from accessing the identified restricted traversable portion, the region having a predefined size and location relative to the initial pose;

obtaining, via a localization sensor coupled to the control circuit, a current pose comprising a second location and a second orientation of the mobile robot on the surface based on localization data detected thereby;

detecting, by the control circuit based on the current pose, that the mobile robot is proximate an end of the region of the surface based on the localization data detected by the localizing sensor or based on a next rank of the path being outside the region of the surface; and

operating, by the control circuit, the drive to move the mobile robot within a different region of the surface having a predefined size and location responsive to the detecting.

17. The method of claim 16, further comprising:

establishing, by the control circuit, a virtual bounding box defining the region of the surface based on the predefined size and location thereof relative to the initial pose, the virtual bounding box at least separating the identified restricted traversable portion from the region of the surface,

wherein operating the drive to move the mobile robot within the region of the surface comprises operating the drive to move the mobile robot from the initial pose to the current pose along the ranks within the virtual bounding box.

18. The method of claim 17, wherein, responsive to the detecting that the mobile robot is proximate the end of the region of the surface, the method further comprises:

operating, by the control circuit, the drive to move the mobile robot to a rank of the path that is within the virtual bounding box prior to movement of the mobile robot in the different region of the surface.

19. The method of claim 17, further comprising:

establishing, by the control circuit, the predefined size of the region of the surface before the mobile robot traverses the surface.

20. The method of claim 19, further comprising:

establishing, by the control circuit, the predefined size of the region of the surface as a static size having one or more fixed dimensions, and confining movement of the mobile robot in the region of the surface to be within the one or more fixed dimensions;

or

establishing, by the control circuit, the predefined size of the region of the surface as a dynamic size having one or more initial dimensions, and expanding the one or more initial dimensions as the mobile robot traverses the surface.