Systems and methods for visual docking in an autonomous mobile robot
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing mobile robot docking systems face challenges in accurately aligning with docking stations, leading to inefficient charging and debris extraction due to misalignment, especially when using co-planar fiducial markers that are close together and far from the dock.
Innovation Solution
The implementation of a three-dimensional (3D) fiducial system using non-coplanar visual fiducial markers on the dock, which allows the mobile robot to detect and adjust its heading direction accurately using a combination of first and second fiducial markers, ensuring proper alignment before contact with the dock.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If co-planar fiducial markers are used on the dock, then the docking system is simpler to manufacture, but the robot's ability to accurately determine heading direction and detect misalignment deteriorates
Solution Approach 1:
The patent transitions from co-planar fiducial markers to non-coplanar fiducial markers, adding a vertical dimension (z-axis) to the marker arrangement. This dimensional change enables the robot to detect misalignment more effectively by providing reference points at different heights, creating a three-dimensional reference frame that improves heading direction determination accuracy.
2Area of stationary object
If fiducial markers are placed close together, then the dock structure is more compact, but the robot's ability to accurately estimate pose and detect misalignment deteriorates
Solution Approach 1:
By arranging fiducial markers in non-coplanar positions with vertical separation, the system increases the effective baseline distance for pose estimation without increasing the horizontal footprint of the dock. The vertical dimension provides additional geometric leverage for accurate robot localization and heading determination.
3Device complexity
If the robot adjusts heading direction based on co-planar markers, then the control system is simpler, but docking alignment accuracy deteriorates due to inability to detect misalignment
Solution Approach 1:
The non-coplanar fiducial marker configuration enables the robot to detect misalignment conditions and provide feedback to the control system. The robot can determine its heading direction relative to the dock normal and adjust its approach accordingly, creating a closed-loop control system that improves docking alignment precision.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enhances docking accuracy and efficiency by providing a robust estimate of the robot's pose and heading direction, preventing misalignment and improving charging and debris extraction processes.
Implementation Method 1
The visual fiducial markers can be retroreflective makers positioned in different planes
Data Source
AI summary
Systems, devices, and methods for docking a mobile robot to a dock using distinct visual fiducial markers on the dock are disclosed. A mobile robot system is provided that includes a dock and a mobile cleaning robot. The dock includes a first fiducial marker in a first plane on the dock and second one or more fiducial markers in a second plane different from the first plane. The mobile cleaning robot includes a visual system to detect the first and the second one or more fiducial markers, and a controller circuit to recognize the dock, and to determine a pose or heading direction of the mobile cleaning robot based on the detected first and the second one or more fiducial markers. The mobile drive system can adjust its heading direction, and drive to the dock according to the adjusted heading direction.