Model Identification of Linear Parameter Varying Aircraft Systems

This article presents a parameter estimation of continuous-time polytopic models for a linear parameter varying (LPV) system. The prediction error method of linear time invariant (LTI) models is modified for polytopic models. The modified prediction error method is applied to an LPV aircraft system whose varying parameter is the flight velocity and model parameters are the stability and control derivatives (SCDs). In an identification simulation, the polytopic model is more suitable for expressing the behaviours of the LPV aircraft system than the LTI model from the viewpoints of the time and the frequency responses. The SCDs of the initial polytopic model are adjusted so as to fit the model output to the output data obtained from the LPV aircraft system.