Kinematic Design and Topological Characteristics of a nT1R-type Reconfigurable Parallel Mechanism

Abstract

In this paper, a new three-degree-of-freedom (3-DOF) reconfigurable spatial parallel mecha-nism(PM), i.e., RPa3R-R+RSS, is proposed based on the position and orientation characteristic (POC) equation.Then, the output motion characteristics of the PM is analyzed, which shows that the moving platform can produce n-translation and one-rotation motion, called nT1R, where n=2 or n=3. The axis of the rotation motion could be parallel to one of the three coordinate axes x,y and z via its reconfigu-rable moving platform. The parasitic translation can be eliminated when the rotation is around x-axis. Moreover, the degree of freedom and coupling degree of the PM are also calculated.