A Grey-Modeling Research on a Small-Scale Autonomous Helicopter

This paper describes a grey-modeling method for small-scale unmanned helicopter that combines the advantages of first-principles modeling and system identification. First, a structure of the attitude model at hovering is developed by strict mechanism derivation and the unknown structural parameters are got. Then, a flying experiment was implemented to get the input and output data. Next, a method combining subspace model identification method and prediction error method is proposed to identify the attitude model and the key parameters of the model are obtained. Finally, comparisons between predicted responses and flight experiments at hovering show excellent agreement. The results of simulation suggest that the grey-modeling method is applicable for modeling a small-scale helicopter.