Programming of Path Specific Robot Operations with Optimal Part Placement

In this paper we describe a task level programming system for path specific robot operations. We define path specific tasks as those robot tasks in which the path the manipulator end effector has to follow is fixed and is given, such operations may include welding or sealant application. The initial path selection is made through a graphical interface using a pointing device (such as a mouse) to outline the desired path on a CAD model of the workpiece. The final result of the system is the part location, which enables the chosen manipulator to optimally perform the desired task. Optimality is based on maximizing the manipulability of the manipulator performing the task using a function of the jacobian. User defined constraints, joint limit constraints, and collision avoidance constraints are used to guide the optimal location selection. The workable task is then executed using calls to a C language based motion control library outlined in [Guptill88] [Guptill & Stahura 87]. The usefulness of the system described in this paper is indicated by an example of two robotic devices performing a down-hand welding operation