ABSTRACT
In this paper, a point to point robot path planning problem is studied. It occurs in industry for example in spot welding, riveting and pick and place tasks.
A new A* -based method is presented. The algorithm searches the robot’s configuration space with many different resolutions at the same time. When a path candidate goes far from the obstacles, a coarser resolution is used. When it goes near the obstacle surfaces, a finer resolution is used.
A* is applied because of the possibility to generate better guiding heuristics. A better admissible heuristic roughly means that A* using it expands fewer configuration space nodes, which is known a priori.
A known AI-method utilizing relaxed models is applied to generate admissible heuristics. Constructing relaxed models involves removing details from the base level problem to get simplified ones. The heuristics are then obtained by solving these simplified problems.
A simulated robot workcell is provided for demonstrations. The path planning of a 5-degrees-of-freedom industrial robot appears to be reasonably fast.
