New metric for wrench space reachability of multifingered hand with contact uncertainties

This paper presents an analysis of object grasping with a multifingered robot hand. Uncertainties on the contact orientation and location are investigated and taken into account to find a new grasp quality measure. This new metric allows to evaluate the controllability of the system and find the Reachable Wrench Space under Uncertainties, a new set introduced in this paper. It includes all the wrenches a grasp can apply whatever the uncertainty is, and gives information about the robustness of the grasp relative to disturbances. Two algorithms are proposed to estimate this new set. Several study cases are presented and tested in simulation to illustrate the new quality metric.