Velocity performance analysis of a novel 2-DOF fully-decoupled spherical parallel mechanism based on performance atlases

This paper describes a novel 2-DOF parallel spherical mechanism named as RR&PRR. This kind of parallel mechanism is composed of two legs and fully decoupled. In this paper, the spatial model of RR&PRR mechanism is established by employing the non-dimensional method to design mechanisms. And the method of describing the performance indexes of velocity is given. Also, a novel method to describe the mechanism´s velocity performances by using the mean value of performance indexes and its fluctuation is proposed. The atlases of velocity performance are drawn in the form of contour series. The effective ranges of the non-dimensionally designed linkage length are determined under different requirements for velocity performance indexes. This study will pave a way for the application of decoupled spherical parallel mechanism.