Two-dimensional Control of Self-servo Track Writing for Hard Disk Drives

Self-servo track writing (SSTW) process for hard disk drives (HDDs) is described by using a two-dimensional (2D) model, with which the error propagation containment problem of the SSTW is formulated as 2D stabilization problem, and the position error minimization problem is formulated as 2D H₂ control problem. The adopted 2D controller is designed with easily implemented linear matrix inequality (LMI) approach. With the stored error information of previous track, the 2D control scheme is realizable. The simulation results demonstrate that the error propagation is prevented by the 2D control scheme and the positioning accuracy is remarkably improved by the 2D H₂ control scheme. Also, from the 2D controller servo performance is evaluated in usually concerned 1D sense