Output Regulation in Discrete-Time Bimodal Linear Systems Subject to Deterministic and Random Exogenous Input Signals

This paper considers an output regulation problem for a class of discrete-time switched bimodal linear systems against known deterministic exogenous signals in the presence of unknown random disturbances, which is motivated by the flying height regulation problem in hard disk drives. The regulation problem for the switched system against the known deterministic exogenous signals is approached by constructing a set of observer-based parameterized stabilizing controllers that satisfy a sufficient regulation condition for the switched system. An H₂ performance constraint is then added to identify, from among the already constructed regulators, those that provide the best H₂ performance against the unknown random disturbances. The proposed regulator is successfully evaluated on a bimodal switched mechanical system experimental setup to demonstrate the effectiveness of the proposed regulation approach.