Damping Control of UAV Wing through Foam Application at Selected Locations within the Airfoil

Unmanned Aerial Vehicles (UAVs) are exposed to harsh and undetermined operating conditions and external vibrations. As a result, they may experience high levels of aerodynamic and mass imbalances, mechanical malfunctions, and atmospheric turbulence. Therefore, it is crucial to have a reliable yet efficient system to mitigate vibrations and ensure the stability of the UAV while experiencing harsh conditions. It is especially important to ensure wing stability as the vibrations that they undergo typically have more extreme amplitudes, increasing both the risk of structural failure in the wings and the instability of the entire structure. This study aims to mitigate the vibration on the wings by providing an efficient yet dependable passive vibration control by utilizing multiple materials for construction. These different materials provide multiple damping coefficients, allowing for a broader range of frequencies to be dampened. Various material properties have been considered to determine the optimal configuration to increase the vibration damping during various operating conditions. The airfoil shape used for this study is the same used by Northrop Grumman on their RQ-4 Global Hawk (NASA LRN1015). Based on data from SolidWorks simulations on a custom-made UAV Blade, an in-house experimental set was developed to illustrate the performance and functionality of the proposed system for various operating conditions. These conditions include both sinusoidal loading as well as random vibration conditions. The loading was applied by the Sentek Dynamics Benchtop (BT - Series) Air-Cooled Shakers. The Spider software collected data from an accelerometer attached to the wing. This demonstrates both the effects of damping and the severity of vibrations on the airfoil in many different operating conditions. Repeating this experiment with different locations and types of foam will determine the optimal conditions to reduce vibrational stress while minimizing additional weight.