Time optimal planning of trajectories for a Similar-SCARA parallel manipulator with limbs of embedding structures

A new type of parallel manipulator with limbs of embedding structures, which we call it Similar-SCARA parallel manipulator, is proposed. The quintic multinomial is used to the trajectory planning in the joints space of the manipulator. Considering the characteristic that the Similar-SCARA parallel manipulator carries objects with point-to-point control, the positions, velocities and accelerations of the medial passing point and the permitted maximum velocity and acceleration of the joint are taken as the constraint conditions for the planning. Furthermore, an iterative optimization project for time optimal planning is given, and with the method, the shortest time between the passing neighbor points can be optimized. The smooth curves of the final optimized trajectories, which are obtained by simulation, verify the proposed iterative optimization project feasible.