這篇論文的主要目的在於使用有限元素來分析撓性雙旋轉軸。這個方法的優點在於計算過程中所用來計算撓性雙旋轉軸振動頻率的過程中,能夠有效增加它的準確度。此外，在建立撓性雙旋轉系統運動方程時，考慮了轉動慣性力矩、迴轉力矩效應與剪應力與應變的效應。 而不用像傳統的傳遞矩陣方法,需要額外一個一個的把特性矩陣加入 當撓性雙旋轉系統複雜性提高、所使用的節點數增加時，仍然保有了精確度。 The purpose of the research is that we hope to use a reduced order finite element method to analyze a dual rotating flexible shafts. The advantage of the proposed method is that the largest size of the matrices involved in computing the critical speed of rotating shaft increase it''s accuracy. In addition, the effects of shear deformation, rotary inertia, gyroscopic moments and shear strain are all taken into account as well. However, that didn''t like the traditional transfer matrix method need another to add the characteristic matrices. The accuracy of the obtained results from this method is high, which however inevitably demands computer memory intensivelyfor increasing number of nodes.