Abstract
This paper describes the design and implementation of control software for industrial robotic systems based on concurrent process modeling. A robotic task is graphically specified using Petri nets representing the flow of subtasks and workpieces. Real time multitask control of robots and machines is performed with external gate arcs controlling transition firing such that the dynamic behavior of the real robotic system is in accordance with that of the discrete event model. Implementation using multithreaded programming is described and experimental results show the effectiveness of the proposed control method.