The basic mechanics of traveling underwater have changed little from the early days of hand-powered submarines. After a brief flirtation with underwater oars, submarine designers switched to propellers and never looked back. Since then, engineers haven’t veered much from this formula, even after upgrading the power source from humans to fossil fuels and then to nuclear reactors.
Yet the last few decades have seen a surge of research into novel ways to propel vessels underwater. Jellyfish, stingrays, and penguins have inspired the blueprints for these new technologies. The wave of change is made possible by recent advancements in materials science, robotics, digital imaging, and the science of animal locomotion. Biologically inspired machines never possible before are now being built in labs around the world.
While still experimental, these new machines show how engineers may one day combine some of the grace, speed, and agility of marine creatures with the power and endurance of machines.
One of the most recent developments is by Flavio Noca, a professor at the University of Applied Sciences Western Switzerland. Noca’s fascination with emperor penguins he saw on a television special more than a decade ago led to his latest creation: a penguin-inspired underwater propulsion system. The mechanism is a spherical joint—a ball-shaped structure based on the animal’s actual shoulder—and parallel arms that recreate the unique, torqued flapping motion that allows penguins to jet from 0 to 15 mph underwater in less than a second.
If it can successfully used outside the lab, the idea promises to combine the incredible acceleration and efficiency of penguins with the unprecedented strength, frequency, and rapid rotation possible with machines.
Penguins are just the beginning. Similar experiments derived from the stingray’s undulating fins and an octopus’s high-pressure jets are leading engineers in new directions as well. The next generation of underwater craft is going to be very different than what we've ever seen before.