一种运载火箭时变结构模态参数辨识的确定性演化方法

针对运载火箭的时变结构模态参数辨识问题进行研究，基于时变自回归滑动平均(TARMA)模型，提出一种时变结构模态参数辨识的确定性演化方法。该方法利用小波基函数的良好局部函数拟合能力，将墨西哥帽小波函数作为TARMA模型时变系数的空间基底，构建了基于小波函数的泛函序列时变自回归滑动平均(FS-TARMA)模型，并发展了两步最小二乘估计方法，实现了时变系数的解耦估计。通过有限单元法，建立了阿里安V号芯级运载火箭时变有限元模型，对所提辨识方法进行了验证，结果表明：墨西哥帽小波基FS-TARMA方法能够有效地辨识系统的时变模态参数；与传统傅里叶基FS-TARMA方法相比，具有更好的辨识精度，并且能够准确地反映出模态局部细节特征。

A Time Varying Structure Modal Parameter Estimation Method in Deterministic Evolution for Launch Vehicle#br#

Focusing on the problems of time-varying structure modal parameter estimation for a launch vehicle, a novel time-varying structure modal parameter estimation method in deterministic evolution based on the time-varying auto- regressive moving average (TARMA) model is proposed. The method takes the advantage of a wavelet function in detail representation and uses it as the basis function of time-varying parameters in the TARMA model, and the wavelet basis based FS-TARMA model is finally established. In order to estimate the time-varying parameters in a linear manner, the two-step least square estimation method is proposed. The proposed method is verified by the core stage of Ariane V time-varying finite element model with its counterpart Fourier basis FS-TARMA method, and the comparative identification results demonstrate that the superior achievable accuracy and enhanced tracking capabilities of the Mexican wavelet basis FS-TARMA method.