Online planning of optimal trajectories on assigned paths with dynamic constraints for robot manipulators

This paper addresses time-optimal path-constrained trajectory planning. Given a geometric path for a manipulator, this paper focuses on the selection of the time law along the path. This law minimizes the time required to complete the path and at the same time is consistent with constraints, both at kinematic and dynamic levels. To obtain the optimal law a decision algorithm for the acceleration along the path has been developed. Remarkably, the algorithm is amenable to online implementation, thus allowing for path replanning. An experimental validation on an ABB IRB140 robot is shown.