Singularity Evaluation and Avoidance in Motion Control Process of Parallel Robots

Near the singular point, the motion transmission would degrade and may appear driven uncontrollable. In this paper, a new concept of sub-singular is introduced, and the sub-singular area is expressed with strict algebra description. Through the description of sub-singular atlas, the visualized expression of sub-singular area and trend of singularity are obtained. On this basis, the optimal disturbance point is obtained while the manipulator traverses the singularity hyper-surface and the expression problem is solved. Finally, the application of sub-singular is illustrated in the process of singularity free path planning for parallel robots