A comparison study on the dynamics of planar 3-DOF 4-RRR, 3-RRR and 2-RRR parallel manipulators

This paper presents a comparison study on the dynamics of three planar 3-DOF parallel manipulators, one with 3-RRR structure, and the other two with 2-RRR and 4-RRR structures. The inverse kinematics and Jacobian matrix of these mechanisms are analyzed. The dynamic formulations in the linear form are derived and a dynamic performance index is given to compare their dynamic performances. The results show that the 2-RRR parallel manipulator has the worst dynamic performance.