本文著重於二維磁浮平台控制之應用，磁浮為利用電磁力作用於受控物體上，使物體懸浮於空中無須與物體接觸，避免一般機械定位方式中的摩擦、損耗、粉塵、能量損失等問題，因此可以延長機械物體使用之壽命。然而磁浮系統在平衡狀態為一不穩定系統、非線性、各自由度間之動態耦合、外界干擾、系統多變數變動，所以必須使用適當的控制律。
本文針對二維磁浮平台系統，設計具有強健性的平滑模式控制器(Sliding Mode Controller)，利用模式切換律(Mode Switching law)結合兩種不同的控制器，並提出擾動估測器(Disturbance Observer)於模式切換律中，線上估測系統中的不確定量，以及對外擾能夠有所補償，另外也利用估測值計算隨狀態調變的邊界層(State-dependent boundary layer)以及切換條件(Switching Condition)，藉以增加系統的強健性。藉由實驗的結果，其有效性亦獲得進一步的驗證。

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.

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