Adaptive regulation for motion control of magnetic tape storage systems

Knowledge of the dynamics of the servo actuator can be used to estimate the disturbances present in a digital servo system of a magnetic tape storage system. It is shown how the actuator dynamics can be used to parametrize perturbations on the control algorithm to minimize the effects of periodic disturbance via adaptive regulation. The approach relies on a fractional representation of the actuator dynamic model and a parametrization of the servo controller that preserves convexity of the minimization of the effects of the disturbances. Motion control experiments of a servo actuator in a Linear Tape Open (LTO) drive operating under feedback with noisy and periodic components in the position error signal measurements will be used to illustrate the effectiveness of the adaptive regulation for the LTO drive under varying disturbance conditions. The results show the possibility to implement a motion control system with adaptive regulation that cancels periodic disturbances with multiple harmonic components.