Collision-free path planning and modification based on task requirements

In order to enhance integration between CAD and robots, we propose a scheme to planning kinematically feasible paths in the presence of obstacles. Thus, the feasibility of a planned path from a CAD system is assured before the path is sent for execution. The proposed scheme imposes a geometrical analysis on a given robot manipulator and obstacles. Consequently, geometrical information describing the robot workspace, obstacles and the planned path can be derived. Then, by utilizing path modification strategies appropriate to various industrial tasks, the planned path can be modified so that it is kinematically feasible and collision-free and satisfies task requirements. The analyses in this paper are based on multiple arbitrarily-shaped obstacles and general non-redundant wrist-partitioned types of robot manipulators in which the joint axes are either perpendicular or parallel to one another. For demonstration, simulations based on using the PUMA 560 robot manipulator to perform different tasks in the presence of obstacles were conducted.