Calculation and Analysis of the Spatial Motion Trajectory of the Grasping Mechanism of a Pipe Handling Manipulator for Coal Mines
Xiao Long Gao *
North China University of Water Resources and Electric Power, China.
Lian Feng Ma
North China University of Water Resources and Electric Power, China.
*Author to whom correspondence should be addressed.
Abstract
Background: Coal mining operations rely on pipeline systems for essential functions, yet installation is often manual, inefficient, and hazardous in confined underground environments. With the shift toward intelligent mining, automated manipulators require accurate kinematic modeling and trajectory planning to ensure safe and efficient pipe handling.
Aims: This paper aims to systematically investigate the spatial motion trajectory, reachable workspace, and pose variation characteristics of the grasping mechanism in three-dimensional space. Its primary objective is to enable precise movement of the manipulator arm and its end-effector within the confined space of mine roadways during pipeline installation. This ensures strict avoidance of contact or collision with surrounding structures, such as sidewalls and the roof. By establishing an accurate kinematic model and conducting simulation analyses, this study seeks to provide a theoretical foundation for optimizing structural parameters and developing motion control strategies for the grasping mechanism, thereby fundamentally ensuring the safety, reliability, and efficiency of pipe-handling manipulator operations in hazardous underground mining environments.
Study design: The research employs a combined theoretical modeling and simulation approach, integrating kinematic analysis with dynamic simulation to validate the mechanical design.
Methodology: Based on operational requirements for pipe handling in underground mines, an integrated structural scheme was developed. The Denavit-Hartenberg (D-H) parameter method was employed to establish a kinematic model of the grasping mechanism. The workspace and end-effector trajectory of the manipulator were computed using the MATLAB Robotics Toolbox, while a virtual prototype was developed in ADAMS to simulate the complete grasping process.
Results: The designed grasping mechanism achieves a maximum horizontal operating range of 3450 mm and a maximum vertical operating range of 2643 mm. The actual spatial motion trajectory from ADAMS simulation closely matches the thermal cloud map results from MATLAB simulation, with correlation coefficients exceeding 95%. Component motion analysis confirms that all displacements remain within the theoretical workspace boundaries.
Conclusion: The designed grasping mechanism effectively meets the demands for pipe handling, transportation, and laying in complex underground environments. The integrated simulation approach validates both the accuracy of motion planning and the consistency of the simulation models, providing a robust foundation for practical implementation in coal mine operations. However, it is important to acknowledge that the current validation is exclusively simulation-based. Future work must involve physical prototype testing under real-world mining conditions to comprehensively verify the mechanism's performance and reliability.
Keywords: Coal mine pipe handling machine, kinematic analysis, spatial trajectory, dynamic simulation, MATLAB, ADAMS