A Collision-free path planning approach based on rule guided lazy-PRM with repulsion field for gantry welding robots

In shipbuilding, various complex welding workpieces and large flexible workspaces bring great challenges to the automated intelligent welding system. In order to maintain the efficiency of primary assembling under a dual-manipulator welding gantry system, a rule-based lazy Probabilistic Roadmap Method (PRM) with a repulsion field is proposed to realize the collision-free online path planning system. It combines manual rules and the repulsive force field, which reduces computational complexity and maintains safety at work compared with traditional Lazy-PRM. Besides, the method plans paths in Cartesian space considering the coordinated movement between manipulators, welding guns and the gantry frame. The proposed method was tested in simulated and practical application scenarios, which proves its effectiveness in solving collision-free online path planning problems for the arc welding gantry system.