Abstract
Utilizing electr-magnetic force to lift or suspend the controlled object on the air without contact, a maglev platform can perform friction loss, dust free and minimal energy loss in most mechanical applications. A maglev system is inherently unstable with nonlinearity, dynamic coupling between each directions and external forces, controller design to provide adequate stability is thus sophisticated. This thesis presents a robust sliding mode control (SMC) design with mode switching law on a two-dimension maglev platform. The controller combines the salient features of different controllers to provide robust performance. An on-line disturbance observer is employed to estimate uncertainties of the system. By using this on-line estimate a state-dependent boundary-layer can be obtained, accompany with switching conditions, robust performance can be enhanced. Several experimental results farther validate its efficacy.