Mother Nature Knows Best: Biomimetic Subs Inspired by Bluegill Sunfish
Biomimicry is nothing new to many TreeHuggers, as witnessed by our pick of biomimetic designs here. Or howabout our posts on scientist mimicing the elastic properties of fleas' knees, . For those of you not familiar with the term, it is essentially design that either imitates life, or at least takes its cue from nature – a fuller definition can be found via our post here. Now we’ve come across a fascinating example of biomimicry on the BBC website, namely a concept for submarines designed to mimic the efficient movements of the bluegill sunfish:
"The bluegill sunfish (Lepomis macrochirus) moves with great efficiency; its pectoral fins are able to propel it creating very little backwards thrust. Where most fish move by flapping their fins back and forth, the bluegill sunfish uses a "cupping and sweeping" motion. Its fin sweeps forwards then curls at its lower and upper edges to create a cup-like shape. This produces a thrust that propels the fish with very little water resistance."
Apparently researchers hope that these subs could be put to use mapping oceans, surveying shipwrecks or sweeping for mines. Of course this isn't the first time biomimetics has taken inspiration from fish - check out this super-aerodynamic car. Just another example of what we can learn from the extraordinary design skills of Mother Nature…
[Update: Fellow TreeHugger informs us that the swimming efficiency of a tail going side to side is potentially much higher than a propeller (when looking at the biomechanics):
"Called Froude Propulsion Efficiency - it is a way to determine a rough estimate of propulsion techniques....Biologsits have characterized many different types- the undulating body of fish has the highest efficiency approaching 75-90%. (marine mammals like dolphins also get up to around 90%)" - from the book Comparative Biomechanics - by Steven Vogel]::BBC:: via site visit::