On Computing All Immobilizing Grasps of a Simple Polygon with Few Contacts

Algorithms for Constructing Immobilizing Fixtures and Grasps of Three-Dimensional Objects

We address the problem of computing immobilizing xtures and grasps of three-dimensional objects, using simple xturing devices and grippers with both discrete and continuous degrees of freedom. The proposed approach is based on the notion of second-order immobility introduced by Rimon and Burdick 48, 49, 50], which is used here to derive simple suucient conditions for immobility and stability in...

On computing optimal planar grasps

The quality of a grasp can often be measured as the magnitude within which any external wrench is resistible by \unit grasp force". In this paper, we present a numerical algorithm to compute the optimal grasp on a simple polygon, given contact forces of unit total magnitude. Forces are compared with torques over the radius of gyration of the polygon. We also address a grasp optimality criterion...

A theory on grasping objects using effectors with curved contact surfaces and its application to whole-arm grasping

This paper develops a theoretical framework for grasping objects using customized effectors that have curved contact surfaces and presents its application to the problem of robotic whole-arm grasping. We present a collection of immobilizing grasps and cages that can effectively restrain the mobility of a wide range of object shapes including polyhedra. Each of the grasps or cages is formed by a...

The Immobilizing Three - Fingergrasps of Planar

This paper addresses the problem of computing frictionless three-nger immobilizing grasps of two-dimensional objects whose boundaries are described by polynomial splines. Using the mobility theory of Rimon and Burdick, we rst develop a set of equations that describe the immobilization constraints. We then present a grasp planning algorithm which uses exact cell decomposition and ho-motopy conti...

Computing Immobilizing Grasps of Polygonal Parts