10 technologies inspired by nature
After 3.5 billion years of intensive R&D, nature has come up with some ingenious solutions for everything from defying gravity with stickiness to surviving a century-long dehydration using sugar. Cathal O'Connell has a rundown.
In 1941, Swiss electrical engineer George de Mestral went hunting in the Alps and afterwards noticed his clothes, and his dog’s fur, were covered in burdock burrs. This mechanism of clinging to passing creatures is the burdock’s way of spreading seeds across greater distances.
Mestral put one of the burrs under a microscope and discovered the simple hooks which allowed it to cling to loops in his socks and in his dog’s hair.
It gave him an idea and 10 years later, after countless experiments with hooks and loops of various materials, Mestral obtained a patent for a new fabric fastener, which we now know as Velcro.
2. Gecko skin
The secret to geckos’ gravity defying grip turns out to be the rows of tiny hairs, called setae, on its toes. The hairs cling to any surface using the sticky van der Waals force, which only works at microscopic scales.
The advantage is a reversible, strong grip, without the need to deposit an adhesive. In recent years engineers have managed to reproduce similar setae from silicone, leading to myriad variations of gecko-skin technology.
Among them is a gizmo to allow human’s to climb a sheer glass wall, as well as robots able to pull objects hundreds of times their own weight and grippers for space repairs.
A future robot called LEMUR (Limbed Excursion Mechanical Utility Robot), with very gecko-like feet could inspect and maintain installations on the International Space Station.
3. Whale fin wind-turbine
In a Boston gift shop Frank Fish, a biologist, noticed the bumps running along the fins on a statue of a humpback whale, and assumed the artist had made a mistake.
Instead of protruding from the back edge of the fins, the bumps ran along the front edge. But the artist was right. The row of warty ridges create tiny vortices which help the fin cut through the water, and explain the humpback’s surprising agility.
After studying this "tubercle effect", Fish discovered that adding rows of bumps to turbine blades reduced drag and noise, and increased their efficiency.
The whale has not only inspired the new shape of turbine blade but even the name of the company that makes them, Canada-based Whalepower Corporation.
4. Shark skin
Inspired by the microscopic scales on shark-skin, NASA scientists developed a drag-reducing coating for ships. The technology helped the Stars and Stripes win the America’s Cup sailing race in 1987.
The coating was so successful, the competition deemed it an unfair advantage and banned the technology, before later reinstating it.
The scales are also constantly moving, which stops micro-organisms from clinging to the hull, reducing the need for anti-fouling treatments.
5. Bullet train kingfisher
A bullet train emerging from a tunnel generates a tremendous thunderclap due to the air-pressure which builds up in front of the nose.
In the 1990s a Japanese engineer Eiji Nakatsu noticed that kingfisher birds could dive into the water with barely a splash.
His design for the Shinkansen bullet train, based on the kingfisher beak, not only reduced the noise of the train but was also more aerodynamic, using less power and enabling higher speeds.
6. Flight – maple seed
With their rotor-like design, maple seeds whirl in the air as they fall – the lift generated through the spinning allows them to travel much further from the tree.
Lockheed Martin adapted this design for a single rotor drone called Samarai. Its simple design has only two moving parts, and so can be easily miniaturised.
The US Advanced Research Projects Agency (DARPA) has taken on the project and aims to produce the drone to be used for reconnaissance in tight quarters.
7. Leggy robots
On uneven terrain, such as a wild mountainside or the rugged terrain of Mars, legs can get you places wheels can’t go. DARPA has developed a series of four-legged robots based on gods and cheetahs for sprinting to deliver supplies on a battlefield.
Meanwhile NASA is working on a six-legged robot called ATHLETE (All-Terrain Hex-Legged Extra-Terrestrial Explorer). ATHLETE has a wheel at the end of each leg, so can roll when the going’s good – and when it runs against an obstacle it can lock down the wheels and step neatly over.
8. Hive mind grid
Though nobody ever tells them what to do, bees in a hive instinctively sense what jobs need doing and get onto it – based simply on where in the hive they are and what other bees are doing around them.
Regen Energy in the US adapted this so-called "swarm logic" to improve the efficiency of energy grids. Instead of using a central system to redirect power loads, the company’s places local controllers that communicate wirelessly with one another, and figure out on their own where power needs to go.
9. Candy-coated vaccines
Tardigrades are tiny, tough eight-legged micro-animals that live in water. Without water tardigrades dry out but have evolved the amazing ability to reanimate after over more than 100 years.
They do this by coating their molecular machinery, such as DNA and proteins, in a sugar.
Inspired by this idea, several biotech companies, including Biomatrica, from San Diego, and Nova Laboratories, from England, adapted the process to protect live vaccines so that they no longer need to be refrigerated.
The technology "shrink wraps" the vaccines in a glassy film of sugars to keep them effective for six months without refrigeration.
10. Termite buildings
African termites have evolved some clever designs to keep their mounds at a nearly constant temperature, though, outside, it may swing from 40 °C in the day to less than 2°C at night.
Termites construct their mounds with a passive cooling system using a series of vents along the top and sides. Wind blows hot air from underground chambers through the vents and out of the structure, and the termites can even control the airflow by opening or blocking tunnels.
Architect Mick Pearce used a similar strategy when he designed the Eastgate centre, an office complex in Harare, Zimbabwe. Warm air vents out the row of chimneys at the top of the building, while cooler air is drawn up from underground.
The building stays cool without air conditioning and so uses only a 10th of the energy of a conventional building of the same size.