Design of robust controller for high performance servo track writer

In this paper, we propose a control structure to obtain a fast seek settle performance. To achieve the goal, a new trajectory generation and a feedforward method were proposed. To minimize the excitation of the plant´s resonance mode, a convex optimization is used to compute a reference trajectory considering the resonance modes. To improve the settling performance, an add-on type disturbance observer is added to the conventional PID controller. From simulation results we have validated the performance of the proposed method with improved fast settling time and performance while rejecting disturbance.