Frequency domain system identification of a micro unmanned aircraft

Building accurate models is of vital importance for control system and autopilot design of an aircraft, especially for a micro unmanned aircraft. This paper introduces a model identification method based on input-output data collected from flight experiments for a micro unmanned aircraft to design flight control system. Frequency domain system identification, which takes advantage of frequency response method, is applied to derive non-parametric model to improve the model accuracy. The parametric values of longitudinal and lateral dynamics equation are identified respectively. Data collection experiment with special input signal is designed to collect credible flight data for the identification method. Time domain identification method is employed to validate the estimation results. Calculation result of parametric estimation is used as reference. The validation results indicate that the estimated model can be well accepted.