Singularity analysis of fine-tuning Stewart platform for large radio telescope using genetic algorithm

Abstract

A new singularity analysis method for general six degree-of-freedom (DOF) Stewart platform using genetic algorithm (GA) is proposed in this paper. The Jacobian matrix of Stewart platform is first deduced, then the square of determinant of the Jacobian matrix is selected as the objective function, and the minimal of this objective function is searched in the workspace of Stewart platform by the GA. The singularity of Stewart platform depends on this minimal objective function: if this value is zero, the singularity of Stewart platform will take place, otherwise, the Stewart platform is singularity-free. The effectiveness of this new genetic singularity analysis method is validated by the singularity analysis of a six-DOF fine-tuning Stewart platform for the next generation large radio telescope. The results have shown that the fine-tuning Stewart platform is singularity-free, which has laid a solid base for the requirement of high precision trajectory tracking for the next generation large radio telescope.