Abstract
This paper presents a methodology for constraining a spherical parallel manipulator so that it guides a body through five task positions with one degree-of-freedom. A dimensional synthesis procedure is used to constrain links of a 3-RRR spherical parallel manipulator using two spherical RR chains to obtain a spherical ten-bar linkage. For our purposes, we begin with a spherical parallel manipulator that has a base and platform that are isosceles spherical triangles. Inverse kinematics analysis of the spherical manipulator provides a set of relative task positions that are used to formulate the synthesis equations for spherical RR chains. The primary challenge is the analysis of the resulting four loop spherical linkage in order to animate is movement.