关键词: 机器人制造单元, 调度, 多工件类型, 无等待, 分枝定界算法

Abstract: It is shown that finding an optimal schedule for a no-wait robotic cell with multi-type parts is equivalent to finding two correlative sequences：parts input sequence and robot move sequence.The problem is solved by avoiding two types of conflicts which may occur when two or more parts use a workstation or the robot at the same time.The entering times of parts are choosen as the decision variables and a mathematic model is developed with the notion of prohibited intervals.A dynamic branch and bound algorithm based on the graph theory is proposed to search the optimal solution.The computational results on a automated printed circuit board （PCB） electroplating line and some random tests indicate that the algorithm is effective.

Key words: robotic cells, scheduling, multi-type parts, no-wait, branch and bound algorithm