Time-optimal motion planning for n-DOF robot manipulators using a path-parametric system reformulation

Time-optimal motion planning for robotic manipulators consists of moving the robot along a path in Cartesian space as fast as possible. In contrast to time-optimal path following, small deviations from a predefined path are acceptable and can be exploited to further reduce the overall motion time. In this paper, we present a new method to compute time-optimal motions around a path. By employing an appropriate change of variables for the robot dynamics to path coordinates, geometric constraints enter the optimal control formulation in a convenient way. The reformulation of the robot dynamics and the path constraints is illustrated with numerical examples.