On Properties of the Screw Geometry of Contact Wrenches in Multiple Grasping Agents

Abstract Establishing a force-closure contact configuration between multiple contacting agents such as dexterous fingers and an object is one of the main requirements for further object manipulation. Various tools and methods have been proposed in the literature for such analysis and modelling. This paper extends the previous results by the authors and by using basic notions from screw geometry present some preliminary tools for a) locating the next contact wrench given any first two contact wrenches; b) computing the grasping wrenches as a function of the external wrench (force) and c) computing the local friction wrenches between the agents and object as a function of the external wrench. The main contribution of the paper is the application of basic tools from screw geometry and the associated algebra to the problem of planning and analysis of forces in multiple contacting agents.