November 19, 2013
Power Of The Penguin
Researchers will often look to nature for inspiration. After all, nature has evolved to best suit its needs, and so, when trying to create something that nature already has, there is no reason not to try and imitate its design. This is true in all fields, though of late there seems to be a strong uptrend in marine locomotion. First, there was the robot jellyfish, then the stingray-inspired submarine, and now we have a penguin inspired propulsion system. Yes, you heard right: a propulsion system inspired by penguins. Penguins, while lacking the ability to fly, have a remarkable ability to rocket themselves through the water at high velocity. The unique way in which they utilize their flipper-like wings, in addition to their aerodynamic forms, is what allows for this incredible underwater speed, and it was that which has led to this most recent development in aquatic mobility.
Inspired by a picture of an Emperor Penguin, taken from the IMAX movie Antarctica, with the caption of “Emperor penguins may be waddling jokes on land, but underwater they can turn into regular rockets…accelerating from 0 to 7 m/s in less than a second”, published by Nature, Flavio Noca, who at the time was a graduate student at Caltech‘s Aeronautics Department and now teaches aerodynamics at University of Applied Sciences Western Switzerland and the Swiss Federal Institute of Technology, has designed a propulsion system based on a penguin’s shoulder and wing, enabling increased maneuverability and greatly improved hydrodynamic efficiency over many modern propulsion designs. This propulsion system has a spherical joint that allows it three degrees of motion, as well as a fixed center of rotation. The spherical joint allows for unlimited rotational range – something an actual penguin does not have – and acts like a propeller. In order to make this system work, though, Noca and his team needed to overcome many technical challenges based on the design: namely, the lack of rigidity and an inability to generate high torques with a spherical joint. This was done by selecting a parallel robotic architecture for the mechanism, as that gives it rigidity as well as higher actuation capabilities.
Flavio Noca will be presenting this unusual aquatic innovation at the American Physical Society’s Division of Fluid Dynamics meeting held November 24 through the 26th in Pittsburgh, PA.
It is incredible to think that these flightless birds have such an amazing ability to move in the water, and more so that this ability could be utilized in the design of this latest propulsion system. Given recent trends though, I have to wonder what is next? Are we going to see jets inspired by hummingbirds or peregrine falcons? Cheetah inspired cars? Who knows? We will just have to wait and see.
Image Credit: Thinkstock