On the high order sliding mode control of a R/W head track following in hard-disc-drives

In this paper, a Sliding Model Control (SMC) is proposed to deal with a track following problem of a single stage-Voice-Coil (VCM) Motor of a Hard-Disc-Drive (HDD). As to offer a chattering free motion of the HDD due to the presence of hysteresis, the SMC can be improved using a higher order version to enhance the accuracy, the speed and the robustness of the closed-loop system. The two control approaches were tested and compared in nominal conditions as well as situations including external punctual and persistent disturbances. Such a comparative study, as never been conducted before on such a system, aims to highlight the efficiency of the Higher Order Sliding Mode Control (HOSM) controller to achieve good tracking performances.