Design of Additively Manufactured Airframe for Radiation Detection UAV

Unmanned aerial vehicles (UAVs) with autonomous navigation capability provide an excellent platform for performing environmental radiation surveys. Low-cost radiation-detecting drones can be deployed in swarms and encourage explorations of background radiation by students and the general public. However, consumer-grade UAVs lack collision avoidance systems and customization beyond recreational use. As a result, affordable off-the-shelf drones incur a high risk of damage during flight. Therefore, a novel 2 kg-payload drone, named Intelligent Radiation Awareness Drone-Lite (iRAD-Lite), was designed. The development of iRAD-Lite required an efficient methodology for rapid prototyping, fabrication, and structural evaluation. A custom 3D-printable airframe was designed using Fusion360 to incorporate mounts for specific payloads, including a depth camera, LiDAR sensor, and radiation detector. Topology optimization was employed to minimize mass while ensuring mechanical integrity under flight loads. Finite Element Analysis (FEA) in ANSYS Discovery validated the structural performance under expected operational stresses. Finally, the frame was 3D-printed using Fused Filament Fabrication (FFF) on a Bambu X1-Carbon 3D printer, and assembled with avionics to test both form and function. FFF offered cheaper and faster iteration compared to purchasing and modifying off-the-shelf products. The value of the total filament used for creating one airframe is estimated to be approximately $50, far less than the $280 to $600 cost for off-the-shelf airframes. Future work includes reducing mass, creating folding arm mechanisms to decrease storage volume, manufacturing with specialized filament materials, and extensive flight testing of prototypes. Overall, the low cost of materials, rapid prototyping, and versatility of 3D printing proved to be an effective method of airframe design for iRAD-Lite.