Synthesis of a minimum-time manipulator trajectories with geometric path constraints using time scaling

Abstract

SUMMARYThe minimum-time and subminimum-time joint trajectories of manipulators with geometric path constraints are planned in consideration of physical constraints based on kinematics and dynamics. The idea of time scaling is introduced, i.e. a time scale factor k(t) and a set of joint trajectories, called reference trajectories, are used to describe all the sets of trajectories tracing the specified geometric path. The desirable factor k(t) which makes the travelling time as short as possible is obtained by two proposed methods: the first one is an iteratively improving method using B spline, and the second one is a directly minimizing method. These two methods are preferably applied to a geometric collision-free path of a manipulator.