Optimal Design of 6-DOF Parallel Robot Based on Output Frequency Response Function

A novel structural parameter optimization of a class of 6-DOF parallel robot is proposed in this paper. As a flight simulator, the moving platform of 6-DOF parallel robot is expected to generate better dynamic response ability. So, the parallel robot should be designed to provide such performance. Herewith, the forward position analysis with 1-DOF motion is expanded into Volterra series. Its kinematics can be regarded as a nonlinear static system; accordingly, the generalized output frequency response function is analyzed for such SISO system. Because the dynamic response ability can be completely described by amplitude frequency function, the description of frequency optimal design is formulized to find some manipulator geometries that maximize the high-frequency motion of the moving platform relative to the low-frequency movements of links. Finally, the analytical solution of optimization problem is derived and the desired mechanism with better dynamic response ability is found out.