Control Experiments of a Docking Mechanism Composed of a Planar Variable Geometry Truss

Abstract

This paper addresses an experimental docking system using a variable geometry truss (VGT), which is a kind of intelligent adaptive structures. The experimental system is composed of a docking mechanism, a frictionless table system, a computer system, and a vision sensor system. By using the developed experimental system, a PD-control and a computed torque method (CTM) are examined. The dynamics-based control, CTM, shows the superiority over the kinematics-based PD control. This paper proposes a resolved acceleration control (RAG), i.e., a position control, with redundancy considering. The proposed control scheme can avoid a bad condition caused by the redundancy. The CTM and the RAC use the efficient formulation of inverse dynamics that was proposed for real time controls by the present authors. Feasibility and effectiveness of those methods are examined by numerical simulations and experiments.

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