Design and Implementation of a Bone-Shaped Hybrid Aerial Underwater Vehicle

The hybrid aerial underwater vehicles (HAUVs) have promising applications due to their capability to operate in both air and water domains. It is a challenge to balance the rapid maneuverability in both media and the stability at the cross-domain phase. In this letter, Nezha-B, a bone-shaped HAUV prototype, is proposed. The double-layered and staggered quadrotor layout results in a shortened width of the vehicle. Along with the streamlined buoyancy material and lightweight marine thrusters, the underwater speed reaches 1.67 m/s. This allows Nezha-B to reconcile the rapid maneuverability of a slender underwater vehicle and the stability of a quadrotor without the additional morphing mechanics. Meanwhile, Nezha-B weighs 900 g and can pass through circular gaps with the diameter (124 mm) of its aerial propeller, making it portable and capable of operating in narrow environments. Simulations in the air and underwater domains evaluate the trade-off of flight performance and hydrodynamics properties. The integrated amphibious locomotion capability is verified through field tests.