中文摘要：

首先，从昆虫（身体和拍动翅）的动力学方程和N—S方程出发，在一定假设下，将运动方程简化为6自由度刚体的方程，并用线化理论给出了反映昆虫悬停飞行纵向动稳定性的理论解。然后，用完全的动力学方程和N—S方程偶合的数值解对上述理论的简化假设进行了检验。

英文摘要：

The equations of motion of an insect with flapping wings are derived and then simplified to that of a flying body using the ＂rigid body＂ assumption. On the basis of the simplified equations of motion and the N - S equations, the longitudinal dynamic stability of two insects （hoverfly and hawkmoth） in hovering flight is studied. The method of computational fluid dynamics is used to compute the aerodynamic derivatives and the techniques of eigenvalue and eigenveetor analysis are used to solve the equations of motion. The validity of the ＂rigid body＂ assumption is also investigated.