Docking process for recharging an autonomous mobile device

• US 8,515,580 B2
• Filed: 06/17/2011
• Issued: 08/20/2013
• Est. Priority Date: 06/17/2011
• Status: Active Grant

• Current Assignee: Zhigu Holdings Limited
• Original Assignee: Microsoft Corporation
• Inventors: Taylor, Trevor, Wyrzykowski, Michael, Larsen, Glen C., Paull, Mike M.
• Primary Examiner(s): Tran, Khoi
• Assistant Examiner(s): RINK, RYAN J
• Application Number:
  US13/162,795
• Publication Number:
  US 20120323365A1
• Time in Patent Office: 795 Days
• Field of Search: 700/245, 700/259
• US Class Current: 700/259
• CPC Class Codes: B25J 19/005 using batteries, e.g. as a back-up power source
• 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 1/0242 using non-visible light signals, e.g. IR or UV signals
• CPC Class Codes: G05D 1/0246 using a video camera in combination with image processing means
• CPC Class Codes: G05D 1/0274 using mapping information stored in a memory device navigation using map-matching G01C21/30

Abstract

Described herein are technologies pertaining to autonomously docking a mobile robot at a docking station for purposes of recharging batteries of the mobile robot. The mobile robot uses vision-based navigation and a known map of the environment to navigate toward the docking station. Once sufficiently proximate to the docking station, the mobile robot captures infrared images of the docking station, and granularly aligns itself with the docking station based upon the captured infrared images of the docking station. As the robot continues to drive towards the docking station, the robot monitors infrared sensors for infrared beams emitted from the docking station. If the infrared sensors receive the infrared beams, the robot continues to drive forward until the robot successfully docks with the docking station.

Claims

1. A mobile robot, comprising:

a depth sensor;

a drive system;

electrical contacts that mate with electrical contacts of a docking station for the robot;

a processor; and

a memory that comprises a plurality of components that are executable by the processor, the components comprising;

an image generator component that causes the depth sensor to generate an image of the docking station, the image indicative of three-dimensional shape of the docking station;

a comparer component that outputs a signal that is indicative of similarity between the image of the docking station with a previously captured image of the docking station, the previously captured image of the docking station being indicative of the three-dimensional shape of the docking station;

a drive component that controls the drive system to cause the robot to autonomously dock in the docking station based at least in part upon the signal output by the comparer component; and

a handshake component that undertakes a handshake protocol with the docking station by way of the electrical contacts of the robot and the electrical contacts of the docking station, and wherein the drive component causes the robot to drive off the docking station if the handshake component fails to complete the handshake protocol.

2. The mobile robot of claim 1, wherein the depth sensor comprises a camera that captures images of light in a non-visible spectrum.

3. The mobile robot of claim 2, wherein the camera is an infrared camera.

4. The mobile robot of claim 3, wherein the depth sensor comprises an infrared light projector that illuminates the docking station with infrared light.

5. The mobile robot of claim 1, further comprising an infrared sensor, and wherein the plurality of components further comprise a beam detector component that outputs a signal that indicates that the infrared sensor has received an infrared beam emitted from the docking station, and wherein the drive component controls the drive system to cause the robot to autonomously dock in the docking station based at least in part upon the signal output by the beam detector component.

6. The mobile robot of claim 5, wherein the comparer component ceases to compare images captured by the depth sensor with previously captured images responsive to the beam detector component outputting the signal.

7. The mobile robot of claim 1, wherein the plurality of components further comprises a power monitor component that monitors electric charge of a power source of the robot and outputs a signal when the electric charge is above a threshold, and wherein the drive component causes the drive system to drive the robot off of the docking station responsive to receipt of the signal from the power monitor component.

8. The mobile robot of claim 1, further comprising a video camera, wherein the drive component receives a signal captured by the camera and causes the drive system to drive the robot autonomously towards the docking station based upon the signal captured by the camera.

9. The mobile robot of claim 8, wherein the plurality of components further comprises a power monitor component that monitors power state of a power source of the robot and outputs a signal when the power state of the power source drops beneath a threshold, and wherein the drive component causes the drive motor to drive the robot towards the docking station responsive to receiving the signal from the power monitor component.

10. The mobile robot of claim 1, wherein the depth sensor comprises an infrared camera and an infrared projector, and wherein the docking station comprises reflectors that reflect infrared light emitted from the infrared projector from the docking station to the infrared camera.

11. The mobile robot of claim 1, wherein the depth sensor comprises an infrared sensor that is configured to capture infrared light emitted from at least one infrared light emitting diode on the docking station.

12. A method, comprising:

causing an infrared camera in a robot to capture an infrared image of a docking station for the robot, the docking station configured to restore a power source of the robot;

comparing the infrared image with a signature;

identifying the docking station based at least in part upon the comparing of the infrared image with the signature;

causing the robot to dock at the docking station responsive to the identifying of the docking station, wherein causing the robot to dock at the docking station comprises causing electrical contacts of the robot to mate with electrical contacts of the docking station;

undertaking a handshake protocol with the docking station; and

failing to complete the handshake protocol; and

causing the robot to drive away from the docking station responsive to failing to complete the handshake protocol.

13. The method of claim 12, further comprising:

detecting that a remaining power in the power source of the robot is beneath a threshold; and

responsive to detecting that the remaining power in the power source of the robot is beneath the threshold, utilizing vision-based navigation and a map of an environment of the robot to autonomously direct the robot to the docking station.

14. The method of claim 13, further comprising:

prior to causing the robot to dock at the docking station estimating that the robot is a threshold distance from the docking station; and

responsive to estimating that the robot is the threshold distance from the docking station, causing the infrared camera to perform a scan of the environment of the robot to locate the docking station.

15. The method of claim 12, further comprising:

monitoring infrared sensors on the robot for receipt of beams of infrared light emitted from the docking station; and

causing the robot to dock at the docking station based at least in part upon the monitoring of the infrared sensors on the robot.

16. The method of claim 12, further comprising:

causing at least one LED on the robot to emit beams of IR light when the robot is within a threshold distance from the docking station, wherein the docking station comprises at least one sensor that is configured to receive the beams of IR light when the robot is properly aligned with the docking station; and

causing the robot to dock with the docking station based at least in part upon an alignment of the beams of IR light with the at least one sensor on the docking station.

17. The method of claim 12, further comprising:

detecting that a power source of the robot is restored; and

causing the robot to drive off of the docking station responsive to detecting that the power source of the robot is fully restored.

18. A robot that comprises a computer-readable medium that includes instructions that, when executed by a processor in the robot, causes the processor to perform acts comprising:

detecting that a power level in a power source that powers the robot is beneath a threshold;

automatically navigating towards a known location of a docking station based at least in part upon one or more images captured by a camera on the robot and a map of an environment of the robot;

estimating that the robot is within a first threshold distance from the docking station;

causing an infrared camera to capture an infrared image at an estimated location of the docking station responsive to the estimating that the robot is within the first threshold distance from the docking station;

comparing the infrared image with a previously generated signature of the docking station to determine a location of the docking station relative to the robot, wherein the previously generated signature is indicative of a three-dimensional shape of the docking station;

causing the robot to drive towards the location of the docking station determined by comparing the infrared image with the previously generated signature of the docking station;

estimating that the robot is within a second threshold distance of the docking station;

monitoring an infrared light sensor on the robot for infrared light emitted from the docking station responsive to estimating that the robot is within the second threshold distance of the docking station;

detecting that infrared light emitted from a light emitting diode on the docking station has been received by the infrared light sensor on the robot;

causing the robot to dock with the docking station responsive to detecting that the infrared light emitted from the light emitting diode on the docking station has been received by the infrared light sensor on the robot wherein causing the robot to dock with the docking station comprises causing electrical contacts of the robot to mate with electrical contacts of the docking station;

undertaking a handshake protocol with the docking station;

failing to complete the handshake protocol with the docking station; and

driving the robot away from the docking station based upon the failing to complete the handshake protocol.