Mathematical Modelling of a Small Scale Helicopter for Autonomous Flight

This paper deals with the mathematical modelling of a small scale Radio Controlled helicopter for autonomous flight. The model includes the classical 6 Degree of Freedom dynamics but also flap and lag, aerodynamic inflow on the rotors, and the dynamic effect of the so-called stabilizer bar which is used on small scale helicopters. A technique to obtain trim and linearization in the presence of the periodic behaviour of the rotors is also proposed. The effects of the additional dynamics are analyzed with reference to the class 60 helicopter under construction at the University of Reggio Calabria.