A challenge related to the adoption of lightweight, flexible wings is the adverse interactions between aerodynamic and structural forces (i.e. aeroelastic flutter). These interactions can provoke larg..
A challenge related to the adoption of lightweight, flexible wings is the adverse interactions between aerodynamic and structural forces (i.e. aeroelastic flutter). These interactions can provoke large in-flight deformations of the wings and can lead to severe structural damages. Hence, a good characterization of the structural dynamics of an aircraft is required. A ground vibration test was done to perform a modal identification of a small Unmanned Aerial Vehicle (UAV). Here, the aircraft was suspended using a highly flexible spring to emulate free flight conditions while being connected to a vibration exciter shaker, which induced a known excitation to the structure. The experimental data show the identification of three main frequencies: the first symmetric bending mode (8.47 Hz), the first symmetric torsional mode (26.20 Hz), and the second symmetric bending mode (31.71 Hz). Understanding the underlying characteristics behind the adverse interactions between aerodynamic and structural forces can lead to solving the technical challenges behind the implementation of lightweight, flexible wings. Preliminary results show a promising trajectory for further research to be done in the validation of these models. Likewise, this research will have provided insight in the development of design methodologies to safely exploit the benefits of lightweight flexible aircraft.
