Note
Harbor Branch Oceanographic Institution's Engineering Division has developed and patented a highly efficient ring thruster for underwater vehicles. This electric propulsion device has no seals or pressure housings, simplifying maintenance under operating conditions. Light weight and reliability are other design criteria for Harbor Branch's manned submersibles, ROVs and AUVs. Design, performance and applications are described as well as the results of testing for thrust, efficiency, bearing life, and flow patterns with several propeller blade configurations. A counter-rotating unit is under development.