Sampled-data output feedback regulation of magnetic levitation system

In this paper, we present a solution to sampled-data output feedback regulation problem for the cases of known and unknown plant models of magnetic levitation system. For known plant model, Extended Kalman Filter (EKF) and Unscented Kalman filter (UKF) are used to observe states (position and velocity) of two levitated magnetic discs of the plant. However, when plant model is unknown, EKF and UKF cannot perform. In such a case, state-space recursive least-squares (SSRLS) with constant velocity model is employed to estimate states of the unknown plant. The controller is designed using eigenvalues placement. The simulation results show good state observation performance given by EKF and UKF observers. Moreover, the performance exhibited by SSRLS observer for unknown model case, is comparable to the performance of EKF and UKF for known model case.