Development of the snapshot method for six degree-of-freedom flight dynamics simulation for a high aspect ratio wing aerial vehicle

Abstract

In this thesis, a six degree-of-freedom flight simulation was developed considering the flexibility of an aircraft with high aspect ratio wings. A full three-dimensional finite element model of unmanned aerial vehicles was used. The object aircraft has main wings with aspect ratio over 20, and flight for long endurance in high altitude. To consider the flexibility of these aircraft, the present 'snapshot method' was developed that combines aerodynamic - structural dynamics - flight dynamics to analyze dynamic response. By applying this method, MATLAB/Simulink, which calculates the rigid body motion, and MSC.FlightLoads, which is responsible for aeroelastic trim analysis, were tightly linked into the present simulation framework. Using the present simulation, aircraft response under various maneuver conditions was simulated. First, the trim analysis for the level cruise was performed. And the trim parameters, the stability derivative coefficients, and the moment of inertia were determined. Based on these results, the flight dynamics of the aircraft was simulated according to the operation of the rudder and the aileron control surface. And the effect of the rigid and flexible body assumptions were confirmed. Also, these results were compared with the other existing simulation results based on the multibody dynamics under the same conditions. In order to predict the response of the aircraft under the gust, the simulation was performed by applying the two-dimensional 1-cosine discrete gust profile.