Control Design for Hard Disk Drives

performance, resulting in equal or better performance than existing LMI based methods. The proposed control algorithm is applied in the control design for hard disk drives (HDDs) where the problem of minimizing track misregistration (TMR) in the presence of unmodeled dynamics of voice-coil motor (VCM) is formulated as a mixed control problem. The simulation and implementation results of the new control design for the VCM actuator demonstrate the significant performance improvement of TMR over the existing method of [19] while ensuring robust stability under unmodeled dynamics of VCM. Index Terms—Hard disk drives (HDDs), control, control, linear matrix inequalities (LMIs), servo control.

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