A fast fish-like human-powered racing submarine
In July 2016 the Auckland Biomimetics Lab’s human-powered fish-like submarine ‘Taniwha 2’ won the 3rd European International Submarine Races (EISR) at the QinetiQ Ocean Basin Gosport, England. Like its 10 competitors, Taniwha was pedal powered, driven by a pilot breathing on scuba inside a non-pressurized wet hull. But unlike the majority of its propeller-driven rivals Taniwha was powered by fins; a modified double Hobie mirage drive with one set on top and another set underneath, mimicking the dorsal and anal fins of a triggerfish. This propulsion design was very reliable; with no aborts in all race starts. The submarine had no rudder for steering, instead, its rear body could flex in a smooth curve, like a fish, under the control of a single hydraulic line. The top speed for this submarine was 4.7 knots, only 0.2 knots short of the world record for a non-propeller driven human-powered submarine.
I will describe development work for our successful Taniwha 2 design and the lessons we learned from our first submarine: Taniwha 1. In 2014 Taniwha 1 competed at the 2 nd EISR, but couldn’t finish the course. We had tried to mimic fish too closely, placing pectoral-like dive planes at the front rather than the rear of the vehicle. Our pilot, lacking the sensory/control system fish have inherited, could not counteract a nose-up or down orientation in time to stop the sub from continuing to rotate beyond the point of no return.
In my talk I will also speculate on the future of human-powered biomimetic submarining.