A constrained motion algorithm for the Shuttle Remote Manipulator System

Abstract

In the past decade, research advances in robot dynamic simulation have included algorithms for space robots operating as open chain mechanisms and earth-bound robot systems operating under motion constraints. Few researchers, however, have investigated a combination of these conditions, i.e., a space robot performing closed chain operations. This article presents a generalized formulation of the dynamic equations for a space-based robot in both open and closed chain kinematic configurations; this generalization represents a consolidation of several specialized formulations found in the current literature. Using this formulation, we present the development of new mathematical models and algorithms for constrained dynamics of the SRMS and their use in supplementing the on-orbit element simulation (OES) developed by NASA and Lockheed Engineering and Sciences Company (LESC). Emphasis is placed on maximizing computational efficiency in order to achieve real time implementation and on minimizing modifications to the original open chain OES code. Simulation results for grasping a fixed payload and frictionless planar sliding of a payload are provided. Constraint violations are minimized using a simple proportional/derivative control technique.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>