In-Grasp Robotic Fine Motion with Frictionless Elastic Point Contacts

Abstract

This paper discusses the form-closure robotic grasping of a rigid object and shows how fine motion of the grasped object may be induced. Preloads are applied along point contacts, a knowledge of whose elastic properties are necessary to overcome statical indeterminacy in the grasp, and whose properties can be exploited to allow the induced fine motion. Appropriate values of these preloads can be derived so as to maintain the grasp against external loads and to induce predefined fine motion to the object. Where a defined fine motion cannot be exactly induced, a best approximation can be found. The analytical approach is supported with examples.