Forward displacement analysis of the asymmetrical 6/6-SPS Stewart parallel manipulator

The mathematical model of the forward displacement of 6/6-SPS Stewart parallel manipulator with a kind of asymmetrical structure was established,and the multivariate polynomial equation set regarding position parameters and orientation parameters of the moving platform of this parallel mechanism was constructed.Based on this equation set and by adopting Mathematica symbolic computation software,a solution program for solving the forward displacement of asymmetrical 6/6-SPS Stewart parallel manipulator was formulated based on Mathematica language.The result that,for any geometric parameters and six given link-lengths of this kind of parallel manipulator,the maximum number of analytical solutions for the forward displacement of this kind of 6/6-SPS Stewart parallel manipulator within the complex domain is 28,and the number of the real solution for its forward displacement should be even.The forward displacement analysis of this kind of the parallel manipulators has laid an important theoretical foundation for the workspace analysis,path planning and control of this kind of parallel manipulators.