Variable-impedance-based human-machine control for docking of manufacturing fixtures

Abstract

Assembly fixtures that are much smaller than the structure being manufactured, such as an aircraft, must routinely be positioned and docked against the structure on which they act.Here, docking implies physical contact between the fixture and the structure. The major contribution of this thesis is to develop a variable-impedance-based human-machine control for the docking process. The major issues investigated are: (i) impedance control to facilitate intuitive human force input; (ii) utilizing variable damping to aid docking and safeguard both the fixture and structure; and (iii) apply a dock force while preserving human control for undocking. A single-degree-of-freedom experimental test bed is used to simulate docking using the proposed controller, and to explore how controller parameter choices impact overall performance.