Abstract
Assembly sequences may require part grasp poses that differ from the implicit assembly insertion axis of RCC-type devices. Since favorable compliant responses accrue only for the insertion axis engineered into the RCC, such “off-axis” poses may obviate its use. The fundamental issue is the creation of an effective compliance that is isotropic in a plane normal to the insertion axis, irrespective of the location of the mechanism. This paper addresses the design of alternative compliant devices, especially an RRR spherical mechanism suitable for industrial application. General compliance requirements are established, mechanism kinematics are developed, and design equations are presented. A laboratory model is described that embodies the desireable features of zero friction, zero backlash, and isotropic stiffness for off-axis assembly tasks.
