Trajectory planning for coordinated motion of a robot and a positioning table. II. Optimal trajectory specification

For pt.I see ibid., p.735-45 (1990). A robot and positioning table system is a kinematically redundant system with respect to planar motion. Two strategies were developed in pt.I to resolve this redundancy and to specify path shapes that make the best utilization of the workspace and speed characteristics of the two devices. In this part, a one-variable dynamic programming approach is developed to obtain a near-minimum time and/or energy trajectory of the two devices. The developed strategies were studied using this path-planning algorithm on a model of a 3 d.o.f. robot and a two-axis linear positioning table for a variety of path shapes and constraints. In addition, experiments were performed in a typical workcell to show the feasibility of the developed strategies. In moving the two devices in opposite directions, the least travel time is obtained when the original path is resolved more in favor of the faster device, whereas the quality of resultant motion is dependent on the controller performance of each device