On minimum time joint-trajectory planning for industrial manipulator with cubic polynomials and input torque constraint

The Cartesian straight line motion has many applications and there are several standard methods to achieve this motion such as approximation by linear interpolation in the joint space. To perform this approximation, however, certain joint trajectories must be constructed at transition points and between the adjacent segments in order that continuity of joint position, velocity and acceleration be met. In this paper cubic spline functions are used to construct these new trajectories. This task is formulated to yield a minimum subtravelling and transition times subject to the manipulator input torque constraints. The applications of these results on minimum time joint-trajectory planning of a three-joint revolute manipulator are demonstrated by computer simulations.