Unified solving inverse dynamics of 6-DOF serial-parallel manipulators

The unified inverse dynamics model of serial-parallel manipulators (S-PMs) formed by two parallel manipulators (PMs) connected in series is systematically established based on the constraint and the coupling characteristics of the single PMs in the S-PM. First, the common formulas for solving inverse kinematics of S-PMs is derived. Second, the inverse dynamics model is established based on the principle of virtual work. Finally, a novel (UPR + RPS + SPS) + (3-SPS/UP) S-PM is analyzed to illustrate the generality and effectiveness of the solving procedures.