Adaptive robust backstepping control design for a non-minimum phase model of hard disk drives

In this paper, a new adaptive robust approach for non-minimum phase systems is proposed, based on the synthesis algorithm of dynamical backstepping design procedure. The previously proposed adaptive robust backstepping method has a limitation in stabilization of non-minimum phase systems, which is removed in this paper. The dynamic model of the voice coil motor actuator, which is used in the read/write head of hard disk drive, is considered as a case study to apply the proposed method. A simple but accurate model of this system is presented the proposed control method is applied onto this model. Simulations are performed for the embedded control system of hard disk drives. The obtained results verify the effectiveness of the proposed control law in terms of transient performance, tracking errors, and disturbance rejection, in both track seeking and track following modes.