Manipulability of cooperating robots with unactuated joints and closed-chain mechanisms

Abstract

We study the differential kinematics and the kineto-static manipulability indices of multiple cooperating robot arms, including active and passive joints. The kinematic manipulability indices are derived extending previous results on cooperating robots without passive joints. The force manipulability analysis for cooperative robot systems cannot be straightforwardly derived by "duality" arguments as it can with conventional arms, rather a distinction between active and passive force manipulability must be introduced. Results in the paper apply directly to the analysis of cooperating robots, parallel robots, dextrous robotic hands and legged vehicles, and, in general, to closed kinematic chains.