Puffin Platform: A Morphable Unmanned Aerial/Underwater Vehicle With Eight Propellers

In this article, a morphable unmanned aerial/underwater vehicle with eight propellers named Puffin platform is investigated. To improve the efficiency of rotor utilization underwater, a tilting mechanism is designed, where the direction of rotors can be changed. As tilting the rotors causes severe underactuation of the vehicle, an attitude control method is proposed. In addition, an adaptive controller is designed for trajectory tracking, and the stability analysis is analyzed by the Lyapunov-like lemma. Simulations are then used to verify the performance of the control strategy. Finally, we assemble the Puffin platform and conduct preliminary experiments to demonstrate its performance in the air, underwater, and during transition.