Robust Tracking Control with £1Adaptive Augmentation for a Long-Stroke Vertical Nanopositioning System: Part I

In this paper and its companion paper [1], we address the problem of modeling and robust adaptive tracking control for an overactuated vertical nanopositioning system. We first introduce the operation principle of the lifting modules. In relation to the integrated actuators, their dynamics and important parameters are obtained from experimental and projected data. We further derive a physical model from the relevant components of the motion system. The model is validated with measured data in order to illustrate that it adequately reflects the real behavior. Emphasis is placed on the merits of control allocation (CA) to handle the overactuated nature of the overall motion system. The proposed CA concept proves to be effective for the ongoing application since it demands low computational costs and fulfills the heat emission constraint. We close this paper with the formulation and analysis of a suitable model for the derivation of advanced control strategies.