用传递函数拟合法优化识别机床的复模态参数

The Optimal Identification Method of Complex Modal Parameters of Machine Tool by Fitting Transfer Function

本文从机床受相对激励的一般情况出发,推导了机床结构的传递函数和模态参数之间的关系,讨论了在非线性阻尼条件下机床结构模态参数的识别方法。在研究线性最优化模态参数识别方法时,本文首先叙述了解矛盾方程比解法方程在数值稳定性方面优越:然后提出采用改进的镜像变换法直接解矛盾方程,既可以提高运算速度又能获得较高的运算精度。

In this paper, the relation between is derived from general situation of machine tool being excited oppositely. The identification method of modal parameters of machine tool under nonlinear damping condition is discussed. Based upon the theory of modal analysis and method of linear optimization, it is proved that solution of contradictory equation is superior to solution of normal equation in stability of numerical value. The way to solve contradictory equation by using householder method is suggested. As the result, the speed of computation is faster and the precision is higher.