Design of a Folding-Wing Submersible Aircraft

Abstract

A submersible aircraft has a large variety of envisioned applications: environmental research, search-and-rescue, surveillance, military defense, etc. Although there have been some success in submersible rotorcraft designs, no successful fixed-wing designs have been demonstrated. Follow-ing bio-inspiration from aquatic diving birds such as the cormorant, a folding wing mechanism is identified as a solution for the large hydrodynamic drag given by the large wingspan of conventional aircraft. The actuation mechanism utilizes a pair of four-bar linkages to constrain the motion of three primary joints to one, allowing for the full contraction and extension of the wing to be actuated by a single servomotor. The mechanism is supported within a detailed, original submersible fuselage design. Although the full manufacture of the design was not attempted, the folding wing mechanism and its integration with a submersible fuselage was conceptually validated by the physical demonstration of a positive result.