微元件為了達到運動的目的，經常使用接頭（Hinge）來作為運動的旋轉對，然而這樣的設計使得元件產生了不必要的磨耗與間隙。因此，微元件若能以撓性機構的型態來呈現是必要的。本論文設計並分析一組微雙穩態元件，此一微雙穩態元件包含了全撓性雙穩態機構與熱驅式致動器。藉由雙穩態撓性機構的特性，使得元件具有撓性機構與雙穩態元件的優點。且經由最佳化設計方法決定了機構的尺寸，並進行運動分析、應變能分析以及應力分析。考慮在穩態位置之間高頻切換時可能產生的動態行為，本研究也進行了相關的動態特性研究。
為了達到自動切換的目的，選擇了熱驅式致動器作為動力來源，使得機構得以反覆自動切換。除此之外，本論文也提出微雙穩態元件應用於光纖切換器的概念。

本論文設計的所有元件都是利用MUMPsTM製作完成。透過實驗測試與觀察，了解微雙穩態元件的可行性。

An increasing number of micro-devices have been designed with compliant hinges and joints to prevent friction and clearance. Furthermore, by proper design this kind of micro devices can possess two stable positions at the two extremes of the motion range, which may be named as bistable compliant mechanism. Bistable mechanisms are excellent for the application of switching devices because they do not consume energy to hold the mechanism in place at the stable positions.
This thesis presents an investigation into the design and dynamic analysis of a bistable compliant micro-mechanism. The dimensions of the bistable compliant mechanism have been decided by optimization techniques. The objective function is to minimize the actuation force in switching between two stable positions. However, the constrained functions contain the fracture strength, existence of bistable behaviors and fabrications. For the application of high operation frequency the dynamic analysis of the bistable compliant mechanism is necessary. Therefore, the modal analysis defining the range of operation frequency for keeping the central mass in straight-line motion is analyzed first. Then, the time of flight between two stable positions is computed from the derived dynamic equations. Finally, the nonlinear transient response analysis at the stable positions has been done by Runge-Kutta computation procedure. The bistable compliant mechanism actuated by thermal actuator arrays is fabricated by MUMPsTM provided by Cronos Integrated Microsystems.

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