Abstract: The generalized 5SPS-1CCS parallel robot mecha- nism and its forward displacement analysis are presented. The mathematic model of the parallel mechanism is created based on quaternion. It is proved theoretically that the forward displacement problem of the generalized 5SPS-1CCS parallel platform has at most 80 nonsingular solutions using Mourrain variety. All 80 nonsingular solutions of the forward displace- ment problem are obtained using homotopy continuation method. The procedure of quaternion manipulation is transformed into that of matrix manipulation and 4 quadric equations are reduced into bi-linear equations in the procedure of the calculation. The efficiency and feasibility are improved through the method proposed above. The result is verified by a numerical example. The analysis results prove that the proposed algorithm is simple and can be used to forward displacement analysis of other generalized parallel mechanisms. The research builds the theory basis for dimensional design, trajectory planning and control of this type of manipulator.

Key words: Forward displacement analysis, Homotopy continuation method Bi-linear equations, Parallel robot mechanism, Quaternion