Trajectory Control of Single Arm Underwater Flexible Welding Robot using Bond Graphs

摘要

Underwater welding robot is a good solution for the welding of ships, submarines and pipes inside the sea because robots do not have to breathe like human being. The problems in trajectory control of the welding torch at the end of the link, because of dynamic coupling between the base and the link, on which various forces acts. The arm deviates from its desired trajectory in presence of buoyant, hydrostatic, hydrodynamic, thrust and other forces. The present work presents the modeling and simulation of trajectory control for one arm flexible underwater welding robot with controller using bond graph, which include the base of plant, one link arm and the motor with overwhelming controller. The underwater robot is modeled considering buoyancy and hydrodynamic forces. The integrated bond graph model was made for the complete underwater welding robot which includes Euler beam model for single arm, base with motor, buoyant and hydrostatic forces and controller. The developed model further allows estimating the deflection of tip in two directions. The complete dynamics of the underwater welding robot is analyzed, which reveals some significant trajectories of the tip in presence of various forces. SYMBOL SONATA software is used for simulating the bond graph model of underwater vehicle.