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.