Interior singularity analysis for a 2(3HUS+S) parallel manipulator with descending matrix rank method
Singularity is one of the basic problems in the analysis of parallel manipulators. A manipulator exhibits instability or transmission performance declination in the singular configuration. In certain serious cases, the normal motion might be damaged. In this study, the Jacobian matrices Jl and Jx of a 2(3HUS+S) parallel manipulator were established based on the topology structure and inverse kinematic analysis. Then, the singular surfaces were obtained by numerical simulation and the locus surfaces were stratified for further description. In addition, the relationship between the motion path curve and the singular surface was analyzed. We found that the 2(3HUS+S) parallel manipulator have a non-singular attitude space in singular surfaces. In the range of small attitude angles, the singular surface is smooth in the middle and steep on both sides. The non-singular pose space increases as the absolute value of γ increases, and singularity could be avoided when γ is large. Furthermore, the motion path curve passes through the singular surface two times, and the two intersection points are consistent with the positions where the motion dexterity is equal to zero. This study provides a new insight on the singular surface analysis of parallel manipulators, particularly for the structure parameter optimization of the non-singular pose space.
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.