Tracking accuracy and stability of a sliding peak-filter based controller for spiral nanopositioning in probe storage systems

High precision nanopositioning is a crucial function of high-density probe-based storage devices and its performance affects determinatively the device´s reliability. The use of non-conventional nanopositioning schemes for achieving much higher data rates imposes new requirements on the control algorithms. In this work we analyze in terms of accuracy and stability an H₂ controller combined with a sliding peak-filter for moving along an archimedean spiral trajectory. As it is demonstrated, proper selection of the peak-filter parameters results to a stable and accurately controlled system that achieves high positioning velocities and also supports different read and write data rates.