Robot management systems for determining docking station pose including mobile robots and methods using same

• US 9,538,892 B2
• Filed: 10/05/2013
• Issued: 01/10/2017
• Est. Priority Date: 10/05/2012
• Status: Active Grant

• Current Assignee: iRobot Corporation
• Original Assignee: iRobot Corporation
• Inventors: Fong, Philip, Meltzer, Jason, Gutmann, Steffen, Karapetyan, Vazgen, Munich, Mario E.
• Primary Examiner(s): Kiswanto, Nicholas
• Application Number:
  US14/046,941
• Publication Number:
  US 20140100693A1
• Time in Patent Office: 1,193 Days
• US Class Current: 1/1
• CPC Class Codes: A47L 2201/02 Docking stations; Docking operations
• CPC Class Codes: A47L 2201/04 Automatic control of the travelling movement; Automatic obstacle detection
• CPC Class Codes: A47L 9/2873 Docking units or charging stations for autonomous or robotic vacuum cleaners A47L2201/02
• CPC Class Codes: A47L 9/2894 Details related to signal transmission in suction cleaners
• CPC Class Codes: A47L 9/30 Arrangement of illuminating devices
• CPC Class Codes: B25J 11/0085 Cleaning
• CPC Class Codes: B25J 13/006 by means of a wireless system for controlling one or several manipulators
• 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: B25J 9/1664 characterised by motion, path, trajectory planning
• CPC Class Codes: B25J 9/1666 Avoiding collision or forbidden zones
• CPC Class Codes: B25J 9/1697 Vision controlled systems
• 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 1/0234 using optical markers or beacons optical beacons per se G01S1/70
• CPC Class Codes: G05D 1/0274 using mapping information stored in a memory device navigation using map-matching G01C21/30
• CPC Class Codes: H02J 7/0045 concerning the insertion or the connection of the batteries
• CPC Class Codes: Y10S 901/01 Mobile robot

Abstract

A mobile robot system is provided that includes a docking station having at least two pose-defining fiducial markers. The pose-defining fiducial markers have a predetermined spatial relationship with respect to one another and/or to a reference point on the docking station such that a docking path to the base station can be determined from one or more observations of the at least two pose-defining fiducial markers. A mobile robot in the system includes a pose sensor assembly. A controller is located on the chassis and is configured to analyze an output signal from the pose sensor assembly. The controller is configured to determine a docking station pose, to locate the docking station pose on a map of a surface traversed by the mobile robot and to path plan a docking trajectory.

Claims

1. A mobile robot system comprising:

a docking station including at least two pose-defining fiducial markers, the at least two pose-defining fiducial markers having a predetermined spatial relationship with respect to one another and/or to a reference point on the docking station such that a docking path to the base station can be determined from one or more observations of the at least two pose-defining fiducial markers;

a mobile robot including;

a chassis,

a motorized drive connected to the chassis for moving the mobile robot to a docked position, and

a pose sensor assembly comprising a sensor configured to output a signal in response to the at least two pose-defining fiducial markers in a pose sensor field of view;

a controller configured to analyze the output signal from the pose sensor assembly, the controller having the predetermined spatial relationship of the at least two pose-defining fiducial markers stored in a controller memory,

wherein the controller is configured to determine a docking station pose that is based on the spatial relationship of the pose-defining fiducial markers and the signals from the pose sensor assembly, and to locate the docking station pose on a map of a surface traversed by the mobile robot, wherein the docking station pose comprises a position defined by location coordinates on the map and an angular orientation of the docking station on the map, and the docking station pose defines a docking lane on the map comprising outside edges and a central axis that is aligned with a central axis of the docking port, and the controller is configured to store the pose of the docking station on the map of the surface traversed by the mobile robot; and

the controller is further configured to path plan a docking trajectory including a curve having a terminal portion aligned with the central axis of the docking lane of the docking station, based on a current robot position on the map of the surface and the docking station pose including the outside edges and the central axis of the docking lane and to provide instructions to the motorized drive to move the mobile robot along the curve of the docking trajectory and into a docking lane within the outside edges and along the central axis of the docking lane of the docking station.

2. The system of claim 1, wherein the controller is located on the chassis of the mobile robot.

3. The system of claim 1, further comprising a database of image data with respect to a plurality of viewpoints of the docking station, wherein the controller is configured to compare the output signal from the pose sensor assembly with the database of image data, and to estimate a pose of the docking station responsive to a comparison of the output signal from the pose sensor assembly with the database of image data.

4. The system of claim 3, wherein the database of image data is generated from a three-dimensional computer model of the docking station and the fiducial markers thereon.

5. The system of claim 4, wherein the controller is configured to path plan a docking trajectory by moving the robot toward the docking lane in response to a current position of the robot and the pose of the docking station.

6. The system of claim 5, wherein the controller is configured to move the robot towards a charging port and/or receptacle of the docking station if the robot is sufficiently close to a predetermined position, and to monitor when the robot connects to the charging port and/or receptacle.

7. The system of claim 3, wherein the controller is configured to path plan a docking trajectory by acquiring images of the docking station, determining the pose of the docking station with respect to the robot, including the position defined by location coordinates on the map and the angular orientation of the docking station, based on the images, and maneuvering the robot in response to the pose of the docking station with respect to the robot.

8. The system of claim 1, wherein the controller determines the pose of the docking station by acquiring data including observations of the fiducial markers of the docking station from at least two positions of the robot and triangulating a location and angular orientation of the docking station in response to the data.

9. The system of claim 8, wherein the fiducial markers are LEDs that are configured indicate a beam direction to the pose sensor assembly.

10. The system of claim 9, wherein the LEDs have different light-emitting characteristics such that the pose sensor assembly is configured to identify an orientation of the LEDs responsive to the predetermined spatial relationship of the LEDs.

11. The system of claim 10, wherein the pose sensor assembly comprises a directional sensor.

12. The system of claim 11, wherein the directional sensor comprises twin photodiodes.

13. The system of claim 11, wherein the fiducial markers are collimated and/or baffled LED lights that generally emit light in a direction such that the pose sensor assembly is configured to plot a line of sight when the robot crosses the emitted light.

14. The system of claim 11, wherein the fiducial markers comprise a portion that transmits IR light and a portion that blocks IR light.

19. The computer program product of claim 14, wherein the computer readable program code is configured to determine the pose of the docking station by acquiring data including observations of the fiducial markers of the docking station from at least two positions of the robot and triangulating a location and angular orientation of the docking station in response to the data.

15. A computer program product for determining a docking path, the computer program product comprising a non-transitory computer readable storage medium having computer readable code embodied in the medium, the computer code comprising:

computer readable code configured to

analyze an output signal from a pose sensor assembly on a mobile robot, wherein the output signal is responsive to an observation by the pose sensor assembly of at least two fiducial markers on a docking station,

determine a docking station pose that is based on a predetermined spatial relationship of the pose-defining fiducial markers and the signals from the pose sensor assembly,

locate a docking station pose on a map of a surface traversed by the mobile robot, wherein the docking station pose comprises a position defined by location coordinates on the map and an angular orientation of the docking station, the docking station pose defining a docking lane on the map comprising outside edges and a central axis that is aligned with a central axis of the docking port, and the controller is configured to store the pose of the docking station on the map of the surface traversed by the mobile robot; and

path plan a docking trajectory including a curve having a terminal portion aligned with the central axis of the docking lane of the docking station, based on a current robot position on the map of the surface and the docking station pose including the outside edges and the central axis of the docking lane and to provide instructions to the motorized drive to move the mobile robot along the curve of the docking trajectory and into a docking lane within the outside edges and along the central axis of the docking lane the docking station.

16. The computer program product of claim 15, wherein the computer readable code is configured to receive a database of image data with respect to a plurality of viewpoints of the docking station, to compare the output signal from the pose sensor assembly with the database of image data, to estimate a pose of the docking station responsive to a comparison of the output signal from the pose sensor assembly with the database of image data, and to store the pose of the docking station on the map of the surface traversed by the mobile robot.

17. The computer program product of claim 16, wherein the database of image data is generated from a three-dimensional computer model of the docking station and the fiducial markers thereon.

18. The computer program product of claim 17, wherein the computer readable program code is configured to path plan a docking trajectory by moving the robot toward a predetermined position in front of the docking station in response to a current position of the robot and the pose of the docking station.

20. A method for determining a docking path, method comprising:

analyzing an output signal from the pose sensor assembly on a mobile robot, wherein the output signal is responsive to an observation by the pose sensor assembly of at least two fiducial markers on a docking station,

determining a docking station pose that is based on a predetermined spatial relationship of the pose-defining fiducial markers and the signals from the pose sensor assembly,

locating a docking station pose on a map of a surface traversed by the mobile robot, wherein the docking station pose comprises a position defined by location coordinates on the map and an angular orientation of the docking station, and the docking station pose defines a docking lane on the map comprising outside edges and a central axis that is aligned with a central axis of the docking port, and the controller is configured to store the pose of the docking station on the map of the surface traversed by the mobile robot; and

path planning a docking trajectory including a curve having a terminal portion aligned with the central axis of the docking lane of the docking station, based on a current robot position on the map of the surface and the docking station pose including the outside edges and the central axis of the docking lane and to provide instructions to the motorized drive to move the mobile robot along the curve of the docking trajectory and into a docking lane within the outside edges and along the central axis of the docking lane of the docking station.