Abstract This paper proposes a model-based observer for state estimation in nonlinear hysteretic structural systems. The observer combines a nonlinear model and response measurements to estimate the complete dynamic response of the structure of interest. The feedback gain of the observer is computed by an iterative algorithm that accounts for the nonlinearity of the system and minimizes the trace of the state error covariance matrix. The main feature of the proposed observer (and its main advantage with respect to existing nonlinear state estimators) is that it is designed to be physically realizable as a nonlinear structural model, which allows the user to benefit from modeling capabilities available in finite element solvers. The performance of the proposed observer is studied in the context of a numerical example consisting of a nonlinear chain model with a Bouc-Wen model of hysteresis subjected to a base motion; the estimation results are compared to those obtained using an unscented Kalman filter. The observer is also validated experimentally using data from a six-story full-scale benchmark wood frame building tested by the NEESWood project at the E-Defense facility in Miki, Japan. The results show the effectiveness of the proposed approach to estimate the dynamic response of large-scale structural systems exhibiting a strong nonlinear behavior.

中文翻译：

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非线性滞回结构系统状态估计的基于扩展模型的观测器

摘要 本文提出了一种基于模型的非线性滞后结构系统状态估计观测器。观测器结合非线性模型和响应测量来估计感兴趣结构的完整动态响应。观测器的反馈增益由迭代算法计算，该算法考虑了系统的非线性并最小化状态误差协方差矩阵的迹线。所提出的观测器的主要特征（及其相对于现有非线性状态估计器的主要优势）是它被设计为可物理实现为非线性结构模型，这允许用户从有限元求解器中可用的建模功能中受益。在一个数值例子的背景下研究了所提出的观测器的性能，该例子由一个非线性链模型和一个受基本运动影响的滞后 Bouc-Wen 模型组成；将估计结果与使用无迹卡尔曼滤波器获得的结果进行比较。观察者还使用来自日本三木 E-Defense 设施的 NEESWood 项目测试的六层全尺寸基准木框架建筑的数据进行实验验证。结果表明，所提出的方法在估计表现出强非线性行为的大型结构系统的动力响应方面是有效的。观察者还使用来自日本三木 E-Defense 设施的 NEESWood 项目测试的六层全尺寸基准木框架建筑的数据进行实验验证。结果表明，所提出的方法在估计表现出强非线性行为的大型结构系统的动力响应方面是有效的。观察者还使用来自日本三木 E-Defense 设施的 NEESWood 项目测试的六层全尺寸基准木框架建筑的数据进行实验验证。结果表明，所提出的方法在估计表现出强非线性行为的大型结构系统的动力响应方面是有效的。