本文利用有限元素法研究撓性連桿含裂縫之曲柄滑塊機構的動態響應。假設機構中的曲柄為剛體及連桿為Timoshenko樑，而連桿上的裂縫考慮為完全開啟的狀態，並利用裂縫之應力強度因子及卡氏定理求得連桿在裂縫處之柔度矩陣。本文利用Hamilton原理推導出系統的運動方程式，然後以Runge-Kutta數值積分方法求得連桿中點及滑塊與連桿交接處之軸向變形 、橫向變形 以及轉角 的暫態響應，並探討連桿有裂縫時對系統動態響應的影響。本文的結果與文獻作比較，兩者差異很小，可知本研究的結果擁有相當高的準確性。此外，數值結果顯示連桿有裂縫時，連桿中點及連桿和滑塊交接處之暫態振幅會比無裂縫時之振幅大。

　In this thesis, the dynamic behavior of slider-crank mechanism with a crack in the flexible linkage is studied. The crank of the system is assumed to be rigid and the flexible linkage is modeled as a Timoshenko beam. The crack in the flexible linkage is modeled as a transverse open crack whose local flexibilities are calculated by using a fracture mechanics approach and the Castigliano’s theorem. The finite element method and Hamiltion’s principle are employed to derive the equations of motion of the system. Dynamic responses are obtained by using the Runge-Kutta method. Influences on dynamic response of the system due to different depths and locations of the crack on flexible linkage are investigated.

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