SMALL UNMANNED AERIAL VEHICLE FUSELAGE DYNAMIC MODEL USING WINGS VIBRATIONS

Range and payloads are the primary design constraints of Small Unmanned Aerial Vehicle (SUAV). These airplanes are made of light weight structures for fuel efficiency and therefore more susceptible to vibrations from atmospheric turbulences and quick maneuver loads that create acceleration and jerkiness transmitted from the wings to the fuselage. The rigid-body vibrations of the fuselage could damage sensitive payloads and avionics. The work presented here explores the predictions of SUAV fuselage vibrations from a state space model. First, a lumped-mass model fuselage vibration is predicted from a state space representation based on wings vibration input using system identification techniques. The state space model is validated with theoretical modal analysis calculations. Second, multiphysics modeling and simulation methods are used on a full SUAV 3D solid model. The wings are excited with point forces on multiple locations on the wings. The resulting wings and fuselage vibration displacements are used to model the fuselage state space representation. And calculations of the fuselage response from the state space model are compared to the output of the multiphysics simulation. The results indicate that fuselage vibrations can be effectively predicted using wings vibration data.