Robust Adaptive Control of Underwater Vehicles with Biologically Inspired Vortex Ring Thrusters

A novel underwater thruster was designed to provide quantized level of thrusts for underwater vehicle maneuvering with a minimal effect on the drag profile of the vehicle. The design was inspired by the efficient and agile locomotion mechanism in squid and jellyfish, which is characterized by formation of vortex rings from pulsatile jets. There have been several successful implementations of the device on a series of autonomous underwater vehicles in our group. In this paper, a robust adaptive control algorithm is formulated for future vehicles with new, more compact thrusters of this type. Control strategy for motion in 6 degrees of freedom, together with corresponding force allocation method is developed and is tested in simulation, where an asymptotic position and velocity tracking result is obtained.