臺灣博碩士論文加值系統

複材夾心樑在靜態及動態研究上(如挫曲、自由振動方面)雖有一些文獻可供參考，但在控制及減震部分則十分罕見，本文以閉合解的方式得到其自由振動及受力振動方程，並以此數學模式進一步去控制其振幅，達到短時間內減振之目的，避免振動時夾心樑的疲勞損害或是破壞情形發生。
本文以壓電材料黏貼於複材夾心樑表面，首先感測器以正壓電效應的方式輸出電壓反映出結構的振動幅度，再以致動器之逆壓電效應產生控制力及力矩輸出，當中利用了線性二次高斯控制演算法(Linear quadratic Gaussian )作為本文之控制方法，形成一回饋控制系統。在估測器選用部份，使用Kalman estimator能使系統在有外擾狀態下，估測最接近真實的狀態，並使用MATLAB 下之simulink 做模擬，並討論控制後之結果。經由此數值模擬，希望能對於複材夾心樑實際振動上達到一較佳的控制結果。

Although some investigations such as buckling, free vibration of composite sandwich beams can be found, it’s rarely seen the research about control and vibration suppression.
In our study, we get the closed form solution of free vibration and forced vibration equations and use the mathematical model to control the amplitude of vibration and achieve the vibration reduction in a short time.
This investigation uses smart composite beams with surface bonded piezoelectric sensors and actuators. The piezoelectric sensors can respond to structural vibration and generate output voltage due to the direct piezoelectric effect. On the other hand, the actuators can induce force and moment and control the system due to the converse piezoelectric effect. We use linear quadratic Gaussian algorithm to be the classical control method and form a feedback control system, and we choose Kalman estimator as an optimal state observer for a system contaminated with plant noise and measurement noise. The numerical simulation of the vibration control was done with the assist of the software MATLAB toolbox simulink.

第一章 序論1
1.1 前言 1
1.2 文獻回顧 2
第二章 複材夾心樑理論分析 5
2.1 夾心樑之假設及描述 5
2.2 自由振動 7
2.3 夾心樑之受力振動 10
2.3.1模態正交化關係 12
第三章 壓電材料分析 16
3.1 壓電感測器 17
3.2 壓電致動器 18
第四章 控制理論分析 21
4.1 最佳控制原理簡介 21
4.2 估測器理論 24
4.3 本系統控制率設計 26
4.4 程式說明及使用方法 27
第五章 結果討論 29
5.1自然振動頻率及自然振動模態驗證 29
5.2 振動控制 30
感測器、致動器種類及其位置選擇 30
第一模態控制結果及雜訊干擾之探討 31
系統強健性研究 34
系統頻譜分析 34
複材面板與等向性面板之控制力比較 35
剪應變對控制力之影響 36
第六章 結論與建議 38
6.1結論 38
6.2未來工作與建議 38
參考文獻40

參考文獻
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