The stingray AUV: A small and cost-effective solution for ecological monitoring

Abstract

Underwater vehicles have recently become more useful in ecological monitoring, largely in part to advanced processing capabilities enabled by modern computers. Most underwater vehicles are torpedo shaped and non-holonomically controlled, which makes them efficient, but they lack precise maneuverability. Some cube-shaped vehicles are used when more exact navigation is necessary; however they cannot take advantage of gliding motions and hydrodynamic lift as their vehicles have a large amount of drag. The Stingray Autonomous Underwater Vehicle (AUV) is a compact, lightweight AUV with a unique design implementation. The hull of the Stingray is a carbon fiber shell with a biomimetic design reminiscent of its ocean-dwelling namesake. This streamlined profile provides very low drag and allows the vehicle to glide through the water. The Stingray also uses a unique propulsion system, combining three vertical thrusters on the wings and tail for roll and pitch with two Voith-Schneider propellers mounted underneath for yaw and surge. In addition, these two propellers provide the ability to strafe, allowing the vehicle to move with six degrees of freedom. This enables the Stingray to easily maneuver at slow speeds and hover in a similar fashion to a helicopter, while also being able to take advantage of the lift generated by its wings to glide like a fixed-wing aircraft.