Thursday, June 04, 2009

Things we can learn from the Mother

Learning Efficiency from Kingfishers
The Shinkansen Bullet Train of the West Japan Railway Company is the fastest train in the world, traveling 200 miles per hour. The problem? Noise. Air pressure changes produced large thunder claps every time the train emerged from a tunnel, causing residents one-quarter a mile away to complain. Eiji Nakatsu, the train's chief engineer and an avid bird-watcher, asked himself, "Is there something in Nature that travels quickly and smoothly between two very different mediums?" Modeling the front-end of the train after the beak of kingfishers, which dive from the air into bodies of water with very little splash to catch fish, resulted not only in a quieter train, but 15% less electricity use even while the train travels 10% faster.

Learning from Lotus Plants How to Clean without Cleaners
Ask any school child or adult how leaves keep water from sticking to them, and they'll almost certainly say, "Because they are so smooth." Yet one of the most water repellent leaves in the world, that of the Lotus (Nelumbo nucifera), isn't smooth at all. The myriad crevices of its microscopically rough leaf surface trap a maze of air upon which water droplets float, so that the slightest breeze or tilt in the leaf causes balls of water to roll cleanly off, taking attached dirt particles with them. Now, microscopically rough surface additives have been introduced into a new generation of paint, glass, and fabric finishes, greatly reducing the need for chemical or laborious cleaning. For example, GreenShield, a fabric finish made by G3i based on the "lotus effect", achieves the same water and stain repellency as conventional fabric finishes while using 8 times less harmful fluorinated chemicals

Learning from Termites How to Create Sustainable Buildings
We generally think of termites as destroying buildings, not helping design them. But the Eastgate Building, an office complex in Harare, Zimbabwe, has an air conditioning system modeled on the self-cooling mounds of Macrotermes michaelseni, termites that maintain the temperature inside their nest to within one degree, day and night (while the temperatures outside swing from 42 °C to 3 °C). The operation of buildings represents 40% of all the energy used by humanity, so learning how to design them to be more sustainable is vitally important. Architect Mick Pearce collaborated with engineers at Arup Associates to design Eastgate, which uses 90% percent less energy for ventilation than conventional buildings its size, and has already saved the building owners over $3.5 million dollars in air conditioning costs.

Learning From Chimpanzees How to Heal Ourselves
One-quarter of all modern medicines are derived directly from plants, and there are hundreds of thousands of other plant species yet to examine, each with dozens of unique chemical compounds that could prove of medicinal value. If one wanted to discover more valuable medicines, where would one start looking? It could take millions of years, literally, to sort through this enormous variety of plants and plant compounds to find ones with medicinal value. Fortunately, this is exactly what researchers have discovered that chimpanzees (Pan spp.) have already done, over millions of years of evolutionary time. By observing how chimps and other species cope with illness, researchers have acquired leads on plants with promising medical applications to human health. Trees from the Vernonia genus, for example, which chimpanzees regularly seek out when ill, have been found to contain chemical compounds that show promise in treating parasites such as pinworm, hookworm, and giardia in humans.

Learning from Dolphins How to Warn People about Tsunamis
Tsunami waves dozens of feet high when they reach shore may only be tens of centimeters high as they travel through the deep ocean. In order to reliably detect them and warn people before they reach land, sensitive pressure sensors must be located underneath passing waves in waters as deep as 6000 meters. The data must then be transmitted up to a buoy at the ocean's surface, where it is relayed to a satellite for distribution to an early warning center. Transmitting data through miles of water has proven difficult, however: sound waves, while unique in being able to travel long distances through water, reverberate and destructively interfere with one another as they travel, compromising the accuracy of information. Unless, that is, you are a dolphin. Dolphins are able to recognize the calls of specific individuals ("signature whistles") up to 25 kilometers away, demonstrating their ability to communicate and process sound information accurately despite the challenging medium of water. By employing several frequencies in each transmission, dolphins have found a way to cope with the sound scattering behavior of their high frequency, rapid transmissions, and still get their message reliably heard. Emulating dolphins' unique frequency-modulating acoustics, a company called EvoLogics has developed a high-performance underwater modem for data transmission, which is currently employed in the tsunami early warning system throughout the Indian Ocean.

Human Lung
Learning from Human Lungs How to Sequester Carbon
Studying the way human lungs work is inspiring new technologies that remove carbon dioxide from sources like flue stacks, preventing this greenhouse gas from reaching our atmosphere and warming the planet. Our lungs have 3 major adaptations which give them their carbon dioxide (CO2) removal effectiveness: a super thin membrane, allowing CO2 to travel across and out quickly (how thin? About one thousandth of the period at the end of this sentence), an enormous surface area (if you laid flat your lungs' gas exchange surface, it would be 70 times your body surface area – about the size of a volley ball court), and specialized chemical translators, namely carbonic anhydrase, which allows CO2 to be removed from our bloodstream thousands of times faster than possible without it. In tests by a company called Carbozyme Inc., human-made filters inspired by the way our lungs work removed over 90% of the CO2 travelling through flue stacks. Meanwhile, other technologies based on the carbonic anhydrase enzyme found in animals such as mollusks have successfully transformed CO2 into limestone, which can be stored or used as a building supply.

Learning from Nature How to Create Flow Without Friction
Stand quietly just about anywhere and you are likely to hear a fan running – in the computer you are using, in the air conditioning unit of the building you are in, and throughout the water, air, and electrical systems upon which the city around you depends. Fans and other rotational devices are a major part of the human built environment, and a major component of our total energy usage. Although we've been building such devices in one form or another since at least 100 B.C., we've never built them like Nature does until now. Naturally flowing fluids, gases, and heat follow a common geometric pattern that differs in shape from conventional human-made rotors. Nature moves water and air using a logarithmic or exponentially growing spiral, as commonly seen in seashells. This pattern shows up everywhere in Nature: in the curled up trunks of elephants and tails of chameleons, in the pattern of swirling galaxies in outer space and kelp in ocean surf, and in the shape of the cochlea of our inner ears and our own skin pores. Inspired by the way Nature moves water and air, PAX Scientific Inc. applied this fundamental geometry to the shape of human-made rotary devices for the first time, in fans, mixers, propellers, turbines and pumps. Depending on application, the resulting designs reduce energy usage by a staggering 10-85% over conventional rotors, and noise by up to 75%.

Learning from Humpback Whales How to Create Efficient Wind Power
Like a school bus pirouetting under water, a humpback whale (Megaptera novaeangliae) – 40-50 feet long and weighing nearly 80,000 pounds – swims in circles tight enough to produce nets of bubbles only 5 feet across while corralling and catching krill, its shrimp-like prey. It turns out that the whale's surprising dexterity is due mainly to its flippers, which have large, irregular looking bumps called tubercules across their leading edges. Whereas sheets of water flowing over smooth flippers break up into myriad turbulent vortices as they cross the flipper, sheets of water passing through a humpback's tubercules maintain even channels of fast-moving water, allowing humpbacks to keep their "grip" on the water at sharper angles and turn tighter corners, even at low speeds. Wind tunnel tests of model humpback fins with and without tubercules have demonstrated the aerodynamic improvements tubercules make, such as an 8% improvement in lift and 32% reduction in drag, as well as allowing for a 40% increase in angle of attack over smooth flippers before stalling. A company called WhalePower is applying the lessons learned from humpback whales to the design of wind turbines to increase their efficiency, while this natural technology also has enormous potential to improve the safety and performance of airplanes, fans, and more.

Learning from Trees and Bones How to Optimize Strength and Materials
The next time you drive through a forest, go ahead and thank the trees out your window for helping on your car's crash safety and gas mileage. Trees engineer themselves in a number of ways to maximize their strength, such as arranging their fibers to minimize stress and adding material where strength is needed (take a look at the extra material beneath a heavy branch, for instance). Bones – unlike trees in that they must carry moving loads – go a step further by removing material where it's not needed, optimizing their structure for their dynamic workloads. Engineers have incorporated these and other lessons learned from how trees and bones optimize their strength and minimize their use of materials into software design programs, such as Claus Matteck's “Soft Kill Option” software, which are revolutionizing industrial design. Using these programs to design cars, for example, has resulted in new vehicle designs that are as crash-safe as conventional cars, yet up to 30% lighter.

TreePrairie Landscape
Learning from Prairies How to Grow Food Sustainably
Take a look at any natural ecosystem, such as a prairie, and you will see a remarkable system of food production: productive, resilient, self-enriching, and ultimately sustainable. The modern agricultural practices of humankind are also enormously productive, but only in the short term: the irrigation, fertilizer, and pesticide inputs upon which modern food crops depend both deplete and pollute increasingly rare water and soil resources. The Land Institute has been working successfully to revolutionize the conceptual foundations of modern agriculture by using natural prairies as a model: they have been demonstrating that using deep-rooted plants which survive year-to-year (perennials) in agricultural systems which mimic stable natural ecosystems – rather than the weedy crops common to many modern agricultural systems – can produce equivalent yields of grain and maintain and even improve the water and soil resources upon which all future agriculture depends