Identification of Aircraft Dynamics Using Hammerstein-Wiener Nonlinear Model

In this article, a new approach based on blockoriented nonlinear models for modeling and identification of aircraft nonlinear dynamics has been proposed. Some of the block-oriented nonlinear models are considered as flexible structures which are suitable for the identification of widely applicable dynamic systems. These models are able to approximate a wide range of system dynamics. Flying vehicle are such nonlinear systems whose dynamics depend not only on pilot control inputs but also on flight conditions, i.e., Mach and altitude. In this study, three systems of Hammerstein, Wiener, and Hammerstein-Wiener for identification and modeling of aircraft nonlinear dynamics have been used and compared. The results of the study show that these models are able to identify and model aircraft nonlinear dynamics. In order to compare each model’s performance, the criteria of the percentage of best fit, final prediction error, and loss function for training data and validation have been considered. The results show that, Hammerstein-Wiener system has a better performance in extracting flexible black-box model based on experimental data from aircraft flight test data. Keywords— Aircraft nonlinear dynamics, System identification, HammersteinWiener modle, flight test.