Biomimetics, or the imitation of nature for the purpose of solving complex human problems, has been around for centuries. Examples are everywhere, from aircraft wings and the treads on tires to climbing robots and solar panels, and in recent years biomimicry has led to new breakthroughs in such areas as fabrication, nanotechnology and biomedicine.
There are so many examples of great nature-inspired engineering. Here are some of the most recent and most interesting.
Bulletproof vests made of spider silk. When we look at a delicate spider web we might not instantly think of strength and durability, but in fact, spider silk is one of the toughest natural fibers known to man, stronger by weight than steel, yet highly flexible. Its potential is endless, with possible applications in the medical industry, apparel, and even defense.
Michigan based Kraig Biocraft Laboratories is studying how to turn spider silk into bulletproof vests for soldiers. Spider webs elongate and flex when bugs fly into them in much the same as a bulletproof vest absorbs the energy of a bullet.
But because spider silk is difficult to harvest for mass production, Kraig Biocraft is genetically engineering silk worms to produce the silk. The lab is starting small with durable spider-silk clothing like gloves and underwear, but hopes a bulletproof vest will be possible down the line.
Everything’s faster with prune power. As the inner flesh of a prune dries and contracts, the outer layer gets wrinkly. You don’t have to be an MIT engineer to have noticed this, but an MIT team is using this natural fact to design a Smart Morphable Surface Smorph that can alter its aerodynamic properties at differing wind speeds. This could make aircraft and even cars more aerodynamic.
The MIT team has created a prototype hollow silicone ball wrapped in a very thin layer of stiffer silicone. Lowering the pressure inside the ball causes the outer skin to wrinkle (or, more accurately, dimple like a golf ball) as it contracts in the same way the skin of a prune does as the inner flesh dries.
Solar panels designed like moth’s eyes. Nocturnal creatures have evolved differently from their day-loving cousins, often equipped with acute hearing, smell, and sight so they can find food in the dark and protect themselves from predators. Swiss researchers are studying the eyes of moths to understand how their structure could be applied to solar technology.
The microstructure of moth’s eyes is adapted to collect as much light as possible, ideal qualities in solar panels. In order to recreate the moth eyes the Swiss team is using metal oxide microspheres.
Walk on water, ant-style. Nothing says teamwork like watching a colony of ants navigate across a stretch of water. Rather than swimming individually, they’ll link onto one another to create a floating bridge or raft.
A team from Georgia Tech froze ant rafts and scanned them with a CT machine. It found that the ants attached to one another with their feet at a force of 400 times their body weight. The ants connect in a way that provides maximum buoyancy, and smaller ants act as stoppers, filling in the holes and cracks between bigger ants to avoid a leaky raft.
Most astonishingly, the ants are able to form these rafts without a coxswain, they react and interact instinctively.
Georgia Tech researchers think this phenomenon can be applied in the human world, perhaps to robots than can link together to build larger robots or bridges made of materials that can self-repair.
A beaky fix for noise pollution. The month marks the 50th anniversary of the Japanese Shinkansen bullet train. But high-speed trains can be noisy, especially when they exit tunnels. Pressure buildup can cause thunderous noise, similar to a loud gunshot that can be heard a quarter-mile away.
Eiji Nakatsu, a bird-watching engineer at the Japanese rail company JR-West, solved this problem by redesigning the nose of the bullet train like a 50-foot-long steel kingfisher beak. Nakatsu noted that a kingfisher creates barely a ripple when it darts into water, even with its long beak. The redesigned nose reduces noise and also cuts down on the power needed to drive the train, enabling even faster speeds.
Elephant pee and a better water tank design. Back to Georgia Tech, and professor David Hu has discovered that the flow rate of urination is controlled by the weight of the fluid in the urethra (and gravity) and not muscular contraction as previously thought.
Hu studied 32 different animals—from elephant to cat—and found that most animals urinate at the same rate regardless of size. Larger animals have longer urethras which increases the flow rate, while smaller animals have shorter urethras which decreases the flow rate, evening out the time.
The Georgia Tech team also noticed that gravity allows larger animals to empty their bladders in jets or sheets of urine, but very small animals—like rats—that experience little gravitational pull tend to urinate in drops.
Why do we care? Because nature has designed a way to use gravity instead of wasting the animal’s energy, Hu says. Using these new findings, the design of water tanks, hydration packs, and fire hoses could possibly be improved.