本文考慮肘節機構內其中一連桿為撓性體，研究肘節機構的動態行為。對機構以多體動力學分析，且我們假設系統中之撓性連桿為Timoshenko樑，即考慮連桿的旋轉慣性以及剪應變效應，以Hamilton原理求得系統之運動方程式和邊界條件，並以滿足邊界條件的Lagrange應變能函數，利用Galerkin方法將機構的偏微分動態方程式化為常微分方程式，以微分值積法求解系統運動方程式以驗證運動方程式之正確性，最後利用Runge-Kutta求得系統的動態反應。本文研究的結果提供含一撓性連桿之肘節機構一個可行的分析步驟及方法。

Dynamic behavior of a toggle mechanism with a flexible connecting rod is analyzed in this study. The mechanism is analyzed by using multi-body dynamics, and the connecting rod is assumed as a Timoshenko beam, namely, effects of the rotary inertia and the shearing strain of the connecting rod are considered. The equations of motion and boundary conditions of the system are derived by Hamilton’s principle. The partial differential equations of motion are transformed into ordinary differential equations by using the Galerkin method with Lagrange strain-energy functions that satisfy the boundary conditions. The correctness of the derived equations of motion is assured through numerical results obtained by using the differential quadrature method. Finally, dynamic responses are obtained by using the Runge-Kutta method. Results of this study provide a feasible method to investigate the dynamic behavior of toggle mechanism with a flexible linkage.

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