Kinematic and singularity analyses of a six DOF 6-3-3 parallel link machine tool

A parallel link manipulator is considered to be an important construction feature of machine tools in the future. To construct a parallel link machine tool which can be practically applied for machining, the analysis of singularity is essential. A six degrees-of-freedom 6-3-3 parallel link machine tool was considered to investigate the effects of the design parameters on the singularity of the system. The U matrix method, which is based on the Plucker coordinate system, is adopted to investigate the singularity of the machine tool. The results show that a little variation of the orientation of the tool frame can effectively avoid the singular condition during the machining processes. This result is important for the applications of parallel link machine tools in real machining processes.