Articles | Volume 11, issue 2
Research article
27 Oct 2020
Research article |  | 27 Oct 2020

Singularity and branch identification of a 2 degree-of-freedom (DOF) seven-bar spherical parallel manipulator

Liangyi Nie, Huafeng Ding, Andrés Kecskeméthy, Jinqiang Gan, Jun Wang, and Kwun-lon Ting

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Cited articles

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Short summary
The main contribution of this paper is to present a kind of 2 DOF seven-bar SPM containing two five-bar spherical loops, which has the advantages of high reaction speed, accuracy rating, and rigidity. And based on the unusual actuated choices and symmetrical loop structure, an approach is provided to identify singularities and branches of this kind of 2 DOF seven-bar SPM. The proposed method is visual and offers geometric insights into understanding the formation of mobility using branch graphs.