Ground Servoelasticity Test and Analysis of UAVs With Large Aspect Ratio and Joined-Wing Layout

Unmanned aerial vehicles (UAVs) with an ultra-large aspect ratio and a joined-wing configuration exhibit characteristics such as minimal mass, remarkable flexibility, and a unified wing structure, thereby presenting a significant challenge in accurately assessing their dynamic behaviors in terrestrial environments. This study focuses on a specific UAV model characterized by an ultra-large aspect ratio and a joined-wing configuration, which underwent experimental scrutiny under free-free conditions, encompassing the entire aircraft. A rubber rope suspension mechanism was employed to support the UAV, and deliberate efforts were made to eliminate the additional stiffness effect, thus facilitating precise determination of the aircraft’s modal characteristics. Subsequent ground-based servoelasticity tests were conducted based on modal experimentation, and specialized filtering techniques were developed to enhance stability. Finally, an analysis of aeroservoelastic stability revealed a strong correlation between simulation and experimental results, with the UAV demonstrating high stability margins in aeroservoelasticity.