Robust Stabilizer Design for High-Precision Tracking of a Linear Gantry*

In this paper, we develop a robust ℋ∞ stabilizer design method for a parallel structure of internal model-based tracking control for a Voice Coil Motor (VCM) driven servo gantry. The physical model of the VCM gantry is discussed and the system augmentation with the internal-model control structure and the exosystem immersion is generated, where the plant model uncertainties are taken into consideration as well. A mixed sensitivity optimization method is introduced for the synthesis of robust stabilizers. Simulations and real time experiments demonstrate good performance of the proposed method for high precision tracking of the servo gantry system.