Thruster Allocation and Mapping of Aerial and Aquatic Modes for a Morphable Multimodal Quadrotor

Although there have been several proposed methods and existing prototypes demonstrating the functionality of aerial-aquatic vehicles, most are fundamentally aerial vehicles with varying degrees of operability when submerged. We aim to improve the balance of aerial-aquatic functionality by proposing a morphable vehicle structure, where the rotors can be tilted to allow thrust vectoring when underwater. Here, in this article, we present a revised prototype implementing the idea and define the details of the aerial and aquatic modes as they are distinctly different from any existing configurations and require unique RC input to actuator output mappings. Based on the first principles model derived from the vehicle structure, we developed an appropriate thruster allocation and mapping system that will allow a single user to control the vehicle manually in both aerial and aquatic modes.