Kinematic analysis of RSCR spatial four-link mechanisms

摘要

The formulas for displacement and velocity analyses are derived for a spatial four-link mecha- nism with two revolute pairs, a spherical pair and a cylindrical pair. Then, a procedure for determining instantaneous screw axes is presented and their behaviors in the neighborhood of limit positions are clarified. The condition for limit positions of the driving-link motion is obtained on the basic of force transmission from the coupler link to the driven link and the determinant composed of the coefficients of simultaneous equation for velocity analysis.