本文將介紹一套方法，在考慮不同負載頻率下，使用商用有限元素軟體Abaqus，建立起衛星減震器設計的分析流程。衛星在發射時會承受到嚴苛的動態負載，為了保護衛星裡電子元件的安全，以提高任務成功率，常常需要為衛星設計減震器。因為減震器所用來消散振動能的黏彈性材料，大多有材料性質會隨著環境負載變化而改變的特性，這可能會影響到減震器的性能。為了研究這種材料特性，本論文使用由奈米級二氧化矽與聚丙烯乙二醇混合之剪切增稠溶液(Shear Thickening Fluid, STF)，此材料有隨著剪切速率提高，而提高其黏滯係數的特性。再透過對STF材料的流變儀試驗，以了解對此類型材料的材料性質以及其測試方法。最後再與其他文獻的測試結果做比較，以了解此材料的特性，與製程的細節。為了連結剪切增稠材料的性質於真實結構上的反應，並探討與流變儀測試的結果是否一致。本論文以剪切增稠材料當三明治夾心樑結構的夾心層，再利用小型激振器，執行振動樑試驗(Vibrating beam testing)，研究此三明治樑於懸臂條件下的反應。最後再利用商用有限元素軟體Abaqus模擬此類型材料應用於減震器設計上的反應。並利用衛星環境測試條件規範，探討在製作衛星減震機構時，如利用材料性質會隨著負載頻率變化而改變的材料，所產生的影響與後果。

The thesis proposed how to design a vibration absorber under dynamic loadings with different frequency by using Finite Element code – ABAQUS. When a satellite launched, it is tolerated with complicated dynamic loadings. In order to protect electrical equipments in satellite, how to design a specific vibration absorber to improve the dynamic response seems important. Frequency-dependent viscoelastic materials are applied to absorbers in order to further dissipate energy. In addition, these kinds of viscoelastic materials will affect absorber’s performance obviously. Thus, in order to understand these dynamic behaviors of viscoelastic materials, 14 nm fumed silica particles and polypropylene glycol (PPG) are used to fabricate the shear thickening fluid (STF). Based on test results, when the shear loading is increased, the corresponding viscosity is increased for STF. Upon examining rheometrical tests, it reveals that STF possesses frequency-dependent characteristic in the current work. The relationship between material properties and structural response can be analyzed by vibrating beam testing (VBT). Finally, ABAQUS is used to analyze and design the proposed absorber. All of discussions and influences about absorbers’ performance caused by frequency-dependent material properties under complicated dynamic loading are presented.

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