Dynamic Modeling of Closed-Chain Mechanisms for Multi-Arm Robots

Abstract

A method for the dynamic simulation of multiarm robots by taking the mechanism of various contact types into consideration is proposed. The system of multi-arm robots grasping a common object forms a multiple closed-chain mechanisms. Each arm and the object can be modeled to be an open-chain with kinematic constraints on its end-effector motion. The dynamics of each arm is expressed using the Appel's method, where the end-effector's constraints of each arm are derived from the object motion. As a result, a parallel computation of joint acceleration for each arm can be performed, and various contact types between the end-effectors and the object can be expressed by constraint equations. Numerical examples are carried out to evaluate the validity of the proposed method.