子结构综合法辨识结合部的特征参数

Identification of Characteristic Parameters of Joints by Substructure Synthesis Method

为了获取结合部的等效刚度与阻尼参数,采用子结构综合法来建立结合部辨识方程式,利用模型更新的方法修正已知模型,使修正的模型与已知模型等效,并利用修正的模型来获取所需的频响函数,从而根据完备频响函数辨识出结合部参数。为了保证数值计算的稳定性,采用最小二乘原理将矛盾方程转化为定解方程,并引入加权的概念,使得被测数据能够充分利用。最后通过两个仿真算例来验证该方法的可行性和工程实用性。仿真结果可以看出,该方法具有较高的辨识精度。

A new identification method for joint stiffness and damping has been developed by using the substructure synthesis method and finite element method in this paper.Firstly,the identification equation of joint is established according to the equilibrium and compatibility conditions.Then,the finite element models or lumped parameter models of substructures are established and updated,which will be used to replace the real models and to obtain the data needed.In order to ensure the stability of numerical calculation,the inconsistent solution of the identification equation is translated to the general solution by the principle of least squares,and the concept of weight is introduced to make use of all the measured data.Finally,this method is applied to two simulated examples,and the results indicate that the proposed method has high identification precision.