Kinematics analysis of 2-PRU-PRRU parallel mechanism

Analyses of the inverse and forward positions of a 3-DOF parallel mechanism (PM) along with two rotational DOFs and one translational DOF are presented in this paper. The module of this 2-PRU-PRRU PM is created, and the Jacobian of the 2-PRU-PRRU PM is derived. Boundary, local, and combined singularities are identified based on the Jacobian. The workspace of the 2-PRU-PRRU PM is discussed according to the singularities and condition of a U-joint interference. The 2-PRU-PRRU PM has a simple structure and supplements the 3-DOF PM family with two rotational DOFs and one translational DOF. The 2-PRU-PRRU PM can be applied in the fields of industrial assembly robots, motion simulators, coordinate measuring machines, and parallel machine tools etc.