隨機振動為振動測試中最普遍被採用的項目之一，常用來模擬各種工商產品於實際振動環境之下的耐久性，以確保該產品於生產後的可靠度。本文旨在研製一架構於個人電腦上用於隨機振動測試中振動機的控制器。我們首先對於振動機的操作特性加以分析探討並將相關的控制方式與理論基礎做摘要性的介紹，而後將結合QFT/H∞的控制設計定理應用在具有高度不確定動態特性的振動機上，設計並實驗出一個在高度不確定的條件下，仍然能夠補償整個測試系統已知的頻率特性並維持良好的追蹤與強健特性之控制器。除此之外，對於性質較為複雜的未知待測物，上述之控制方式不足以對整個系統未知的頻率特性加以控制，因此輔助上另一個具有系統鑑別能力控制策略，利用一般的頻率響應估測法對未知動態系統加以鑑別後，利用其結果於頻域中適當的處理後，來消除由未知的待測物與振動機構所引起的機械共振與頻譜失真，達成良好的頻譜控制。巧妙的結合以上這些技巧可達成具有強健性、低成本且高性能的隨機振動測試系統。相關的理論基礎、設計程序與軟硬體實驗皆於本文中詳細的描述，同時，所有設計出的軟硬體系統與所研製控制器的各項性能，均由軟體模擬與硬體實驗後，來驗證其有效性。

A PC-based controller of the eletrodynamic shaker for random vibration test is developed in this thesis. First, the operation characteristics of the shaker and the control approaches are studied. A combined QFT/H∞ design algorithm is employed to design the controller for such highly uncertain dynamic of the shaker. Then the feedback controller is designed and implemented to compensate the known part of the overall test system and to let the shaker maintain fast tracking performance and robustness under extremely uncertain condition. On the other hand, for more complex DUTs, a typical frequency response estimation scheme is first adopted to identify the frequency response shape of the unknown part of the overall test system, and then the resonance and spectral distortion caused by the device under test can be nearly eliminated by manipulating estimated results. A robust, low cost and good quality random vibration test system can be achieved by combining these control schemes properly. The theoretic basis, design procedures and implementation of the controllers are described in detail. Meanwhile, some significant simulation and experimental results are provided to demonstrate the validity of all the designed circuits and performance of the developed controllers.

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