Type Synthesis of Parallel Mechanisms Having Two Rotations

In the last few decades, researchers have proposed a few different methods to synthesize parallel mechanisms. In this paper, we propose both the natural law for kinematic mobility and the generalized function sets (G_F set for short) which are used for the type synthesis of parallel mechanisms, particularly for those having two rotations. The natural law for kinematic mobility lays the foundation for the algorithms of the intersection of G_F sets. Moreover, the G_F sets are used for describing the performance criteria of the end-effectors of robotic manipulators in a clear and systematic way, including the mechanisms having two rotations. Finally, several novel parallel mechanisms having two rotations have been illustrated to show the effectiveness of the proposed methodology.