Mobile Manipulator Surface Tracking with Vision Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for controlling mobile manipulators to track surfaces lack sufficient accuracy, leading to tracking errors that can result in loss of contact or excessive contact force, which is unsuitable for applications like welding, inspection, and industrial processes.
Innovation Solution
A method and system for controlling a mobile manipulator that involves detecting the surface, determining a reference path with an offset, calculating tracking errors using point cloud data and noise filtering, and adjusting the end effector's position and orientation to maintain accurate tracking, employing techniques like Hough Transform and Kalman filter for precise surface tracking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional SLAM methods are used for navigation, then the robot can navigate autonomously, but the surface tracking accuracy is insufficient for delicate applications
Solution Approach 1:
The patent replaces conventional SLAM-based navigation with a vision-based surface tracking system that uses camera sensors to detect surface features and calculate pose information. This substitution of mechanical/navigation-based methods with optical sensing achieves higher tracking accuracy without requiring complex map-building algorithms
Solution Approach 2:
The system creates a visual copy of the surface through camera imaging and uses this optical representation to determine surface pose and guide manipulator positioning. By working with image data rather than physical navigation, the system achieves precise surface tracking
2Measurement precision
If high-resolution maps are used to improve tracking accuracy, then measurement precision increases, but computation speed decreases due to large map files
Solution Approach 1:
The patent extracts only the essential surface pose information from the camera image by detecting specific surface features and calculating pose directly from image coordinates. This extraction approach avoids the need to process and store large high-resolution maps, maintaining both accuracy and computational efficiency
Solution Approach 2:
The system performs preliminary surface detection and pose calculation continuously based on real-time camera feedback before the manipulator needs to adjust its position. This ongoing preliminary action ensures accurate tracking without requiring intensive computation at critical moments
3Measurement precision
If the mobile manipulator maintains a close distance from the surface, then surface tracking accuracy improves, but the risk of losing contact or exerting excessive contact force increases
Solution Approach 1:
The patent implements a feedback control system that continuously monitors surface pose through camera detection and adjusts manipulator position accordingly. This closed-loop feedback maintains optimal contact distance by comparing actual position with desired position and making real-time corrections, ensuring both accuracy and contact stability
Solution Approach 2:
The system dynamically adjusts the manipulator's position and orientation based on real-time surface pose detection. By making continuous dynamic adjustments rather than maintaining a fixed position, the system adapts to surface variations while maintaining stable contact and accurate tracking
Data Source
AI summary
There is provided a method of controlling a mobile manipulator for tracking a surface. The mobile manipulator includes a mobile base movable in an axial direction of the mobile manipulator and a manipulator supported on the mobile base having an end effector adjustable in a lateral direction of the mobile manipulator. The method includes detecting the surface from the mobile manipulator, including positions of the surface at points along the surface, determining a reference path for the end effector to track based on an offset from the surface detected, determining a tracking error in the reference path determined, and adjusting a position of the end effector in the lateral direction based on the tracking error to compensate for the tracking error in the reference path determined. There is also provided a corresponding mobile manipulator.