Helicopter Aerodynamic Parameter Identification Method Study

Aerodynamical parameters in longitudinal model of a certain type of helicopter are identified in the paper. The thesis is composed of three parts, i.e. model choice, experimental data preprocessing, and parameters identification. Longitudinal movement differential function is adopted here as identification model based on analysis of helicopter characteristics; Recognition, rejection and rectification unreasonable data is the first job in the second part. Then a low pass filter is designed to filter high-frequency noise in data. And Smooth data again by means of central interpolation algorithm; Helicopter model with multi input single output are identified respectively in LS method and ML method. Furthermore, parameter identification to complex MIMO model is presented by means of Newton-Raphson iteration method. At last, the paper proves that three above methods, which are compared finally, can obtain exact result.