Adaptive compensation of microactuator resonance in hard disk drives

This article presents an adaptive resonance compensation scheme for microactuator-based dual-stage servo system in hard disk drives. The approach is to identify the microactuator resonant modes and compensate the model accordingly to a simpler one by pole-zero cancellation. Consequently, the servo controller can be designed based on the compensated fixed model despite actuator resonant mode variations. Simulation and experiment results show that this adaptive compensation scheme can suppress microactuator resonance without priori knowledge of the resonant modes. This approach makes the servo control system robust against microactuator resonance variations.