A Novel Nanopositioning Stage Integrated With Voice Coil Motor and Active Eddy Current Damper

The flexure-based nanopositioning stages driven by the voice coil motors (VCMs) are increasingly demanded with the advantage of simultaneously achieving millimeter-scale stroke and nanoscale resolution. However, the inherent light-damped property from the flexure guide severely degrades the motion accuracy and the system stability, particularly in high-speed operations. This article proposes a novel flexure-based nanopositioning stage driven by a VCM with an integrated dual-sided active eddy current damper (AECD), which suppresses residual vibrations of the stage and then achieves high-precision performances. Based on the established electromagnetic-mechanical model, the structural parameters are optimized within the size constraints. Model verification and system performance assessment are carried out through finite element analysis. A prototype is fabricated, and experimental results demonstrate that the stage achieves a 20 nm positioning resolution within a 6 mm stroke. The root-mean-square (RMS) tracking errors are controlled within 0.1% of the reference amplitudes for both sinusoidal and triangular trajectories. With the adoption of the proposed AECD, the maximum error and rms error are decreased by 29.50% and 48.46%, respectively. Meanwhile, the settling time is reduced by 66.14% even when the motor follows a high-speed and high-acceleration T-curve trajectory.