Vortex Ring Thrusters for Maneuvering and Control of Underwater Robots*

Inspired by the natural locomotion of squid and other cephalopod, a new type of thruster was designed which utilized pulsatile jet propulsion to generate controlling forces. The thrust production from this device was characterized in a static environment and seen to be well approximated by a simple fluid slug model. A virtual vehicle simulation was developed to test the thruster with unsteady driving signals. Within this environment using a simple proportional derivative feedback control algorithm, the thruster/controller was observed to provide sufficient control over the vehicle performing large scale maneuvers. However, compensation is required for accurate small scale maneuvers due to a thruster time delay which is unmodeled in the simple slug model. +