UoSS Nauti Buoy moves through the gears ahead of international human-powered submarine races
Engineering students from the University of Southampton say they are focussing on gearbox performance as they prepare a human-powered submarine for a competitive race series.
The Southampton University Human Powered Submarine Society (SUHPS) is working with industry partner Igus as it optimises its entry for next year’s International Submarine Races (ISR).
The team are trialling their unique flooded submarine, nicknamed UoSS Nauti Buoy, which will navigate an obstacle course in a timed race through the pedal power of a single scuba diver pilot.
The biennial ISR series encourages young people to fill a shortfall in marine engineers and has attracted interested from over 20 undergraduate students at Southampton studying a range of disciplines including Mechanical Engineering, Mathematics and Oceanography. SUHPS has divided its resources into five distinct sub-teams, each specialising in one area of design and manufacture.
UoSS Nauti Buoy was entered into the European International Submarine Races (eISR) earlier this year in Gosport, but suffered with technical issues during the qualification sessions.
Students found that their initial gear ratio was too high, making it difficult for the pilot to pedal. There was also unwanted sliding of the gears, caused by the supporting frame bending under high loads from the pilot’s pedalling. The outcome was a reduced efficiency of the overall system.
“This academic year, we are using vastly different gear ratios and dimensions and more precise manufacturing methods such as water jet cutting for the mounting plates,” Transmission Team co-leader, and Mechanical Engineering student, Caroline Layzell says. “We have reduced the initial gear ratio to 2:1, which will make the pedals easier to push for the pilot, and redesigned an entirely new frame to house the gears.”
The selection of Igus xiros bearings is enabling a smoother rotation of the propeller and crankshaft within the transmission system.
A new submarine shell, designed by Hull Team leader, and Aeronautics and Astronautics student, Euan French, is currently undergoing fibreglass lay-up following months of meticulous calculations to ensure its shape optimises the trade-off between drag and space for the pilot.
SUHPS was founded in 2014 and has competed in the 2015 ISR in Washington DC with the UoSS Orca and the 2017 ISR in Maryland with the UoSS Kaiju. The 2019 ISR is set to take place from June 24th to 29th.