Kinematic analysis of a fully-decoupled parallel manipulator with pure translations

A spatial 3 degree-of-freedom parallel mechanism is proposed in this paper. It contains only Pa joint and revolute joints in each kinematic chain. The motion of the moving platform is verified by means of the theory of screw. The simple and intrinsic geometric relations are employed to solve both the inverse and forward positions and fully-decoupled property. Its singularity configurations are found by using the Jacobian matrix. The translational workspace is obtained and verified through considering joints and linkages limitations.