Design, Fabrication, and Testing of Fixed-Wing Air-and-Underwater Drone

摘要

Drone technology has evolved rapidly over the last few decades. Some drones fly while others operate underwater. However, there has not been an effective fixed-wing vehicle that can operate between the two environments interchangeably. The purpose of this project is to design, build, and test a prototype that can achieve these goals. This paper presents our high-wing, inverted conventional tail drone with a mass of approximately two kilograms. For the atmospheric flight, a propeller mounted on the nose was used (in a puller configuration); for the underwater operation, a propeller mounted on the rear end of the fuselage was used (in a pusher configuration). The batteries and other electronic components were enclosed in a waterproofed casing, while the balsa wood used in structural reinforcements was surface-treated to avoid water absorption. The total volume and mass were controlled as to achieve the neutral buoyancy when submerged under water. This paper also presents our analyses on aerodynamics and hydrodynamics, vehicle performance in air and underwater, propulsion and power, structure and materials, and the overall strategies to integrate multidisciplinary objectives and constraints into a coherent design. To verify our theory we conducted prototype testing for the air flight, underwater operation, and transition between the two environments. Our air-flight test confirmed that our vehicle was airworthy: it successfully took-off, climbed altitude, and achieved the cruising condition. Our underwater test confirmed that our vehicle was near neutral-buoyancy and that all control surfaces were functional at least when the vehicle was near the water's surface. Additionally, vertical take-off was tested as a water-to-air transition. Drones that would be able to fly and swim would perform missions that are not yet possible. In recent years, a few prototype experiments have been made using quadcopter designs. Our study represents important milestones towards a fixed-wing approach in which the design demonstrates the potential to carry more payloads and fly longer distances.