Characterization and Control of a Piezoelectrically Actuated High-speed Planar Nanopositioner

We report characterization and control of a novel flexure-guided piezoelectric nanopositioner. The positioning range of this high-speed planar scanner is approximately 5.8 µm in both X and Y-directions with the first resonance frequency being above 15 kHz. An integral resonant controller is designed to augment damping to the dominant mode of the X-axis nanopositioner (fast axis). The damping controller is then augmented by a double integrator to provide better tracking performance. As for the Y-axis scanner (slow axis) where a lower bandwidth is required, a notch filter cascaded with an integrator is used to damp the dominant mode and achieve a satisfactory tracking bandwidth. Tracking performance of the nanopositioner in closed-loop with this control system is investigated through experiments where each axis of the nanopositioner is set to track a triangular input with different frequencies.