模型在线辨识方法及其应用

On-Line Model Identification Method and Its Application

中文关键词  模型辨识  在线估计  非线性系统  飞行动力学  飞行试验

英文关键词  model identification  on-line estimation  nonlinear system  flight dynamics  flight test

中文摘要

      本文提出了一种有效的非线性模型和参数在线估计方法。为了实现模型在线辨识，本文根据误差性能指标，给出了模型判据及计算式。根据递推加权最小二乘算法和优选判据，导出了模型和参数同时在线估计的有效算法。为了提高计算效率和数值稳定性，模型辨识和参数辨识均采用了U-D分解方法。新方法可用于飞行器非线性气动模型和参数的实时估计。实际应用结果表明，使用该方法可以有效地确定多项式、样条函数模型结构，参数辨识的结果满足工程要求。

英文摘要

      An efficient on-line identification method for both model and parameter for nonlinear system is presented in this paper. To achieve on-line model identification, a new algorithm is developed which is based on the cost function of error statistics. By means of recursive least square method and model choosing criterion, an efficient on-line method for both model and parameter identification is obtained. To get high numerical stability and computational efficiency, U-D factorization is used in both model and parameter estimation. The new method has been used in the on-line estimation of aerodynamic coefficient of an aircraft. The results of applications show that the models represented by polynominal and spling functions can be determined accurately.