Abstract
A practically applicable collision free trajectory planning technique for tow robot systems is proposed. The robot trajectories considered in this work are composed of many segments, an at the intersection points between segments robots stop to assemble, weld, ordo other jobs by the attached a end-effectors. The proposed method is based on the Planning-Coordination Decomposition where planning is to find a trajectory of each robot independently according to their tasks and coordination is to find a velocity modification profile to avoid collision with each other. To fully utilize the independently planned trajectories and to ensure no geometrical path deviation after coordination, we develop a simple technique added the minimal delay time to avoid collision just before moving along path segments. We determine the least delay time by the graphical method in the Coordination space where collisions and coordinations are easily visualized. We classify all possible cases into 3 group and derive the optimal solution for each group.