A Family of Novel Lower-Mobility Decoupled Parallel Mechanisms

This paper presents a family of novel lower-mobility decoupled parallel mechanisms (DPMs), which consists of one 5-DOF (degree of freedom) DPM, two 4-DOF DPMs, three 3-DOF DPMs, and three 2-DOF DPMs. The basic feature of this family is that the moving platform and the fixed base of the DPMs are connected by two limbs and the motion of the moving platform is fully decoupled. Then the constraint screw method is used to analyze the motion feature of all DPMs presented in this paper. The mobility of these DPMs has also been calculated by the Modified Grubler-Kutzbach criterion. All the DPMs in this paper are simple and no computation is required for real-time control.