Systems and methods for visual docking in an autonomous mobile robot

A mobile robot system, comprising:

• a dock comprising a first fiducial marker in a first plane and second and third fiducial markers in a second plane different from the first plane;
• and
• a mobile cleaning robot including:
• a drive system to move the mobile cleaning robot about an environment including a docking area within a distance of the dock;
• a visual system to produce an image of the dock, and to detect from the image the first, the second, and the third fiducial markers;
• and
• a controller circuit configured to:
• determine, from the image of the dock, (i) a first distance between the detected first fiducial marker and the detected second fiducial marker and (ii) a second distance between the detected first fiducial marker and the detected third fiducial marker;
• determine a heading direction of the mobile cleaning robot with respect to the dock based at least in part on the determined first distance and the determined second distance;
• and
• generate a control signal to the drive system to drive the mobile cleaning robot to the dock in accordance with determined heading direction.

A mobile robot system, comprising:

• a dock comprising first and second fiducial markers disposed on at least one plane parallel to a back plane of the dock, the first and the second fiducial markers having an actual spatial relationship defined on the dock;
• and
• a mobile cleaning robot including:
• a drive system to move the mobile cleaning robot about an environment including a docking area within a distance of the dock;
• a visual system to produce an image of the dock, and to detect from the image the first and the second fiducial markers;
• and
• a controller circuit configured to:
• measure, from the image of the dock, a spatial relationship between the detected first fiducial marker and the detected second fiducial marker;
• determine a heading direction of the mobile cleaning robot with respect to the dock based at least in part on (i) the actual spatial relationship between the first and the second fiducial markers defined on the dock and (ii) the measured spatial relationship from the image between the detected first fiducial marker and the detected second fiducial marker;
• and
• generate a control signal to the drive system to drive the mobile cleaning robot to the dock in accordance with determined heading direction.

A method for docking a mobile cleaning robot to a dock, the method comprising:

• receiving information about an actual spatial relationship between first and second fiducial markers disposed on at least one plane parallel to a back plane of the dock;
• generating an image of the dock via a visual system of the mobile cleaning robot prior to docking, and detecting from the image the first and the second fiducial markers;
• measuring, from the image of the dock, a spatial relationship between the detected first fiducial marker and the detected second fiducial using a controller circuit;
• determining, via the controller circuit, a heading direction of the mobile cleaning robot with respect to the dock based at least in part on (i) the actual spatial relationship between the first and the second fiducial markers defined on the dock and (ii) the measured spatial relationship from the image between the detected first fiducial marker and the detected second fiducial marker;
• and
• controlling a drive system of the mobile cleaning robot to drive the mobile cleaning robot to the dock in accordance with determined heading direction.