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The latest inventions are inspired by the world around us.
By Vicki Haddock

Professor Robert Full is used to fielding bizarre calls: It might be the Department of Defense on the line inquiring about swimming robots, or Pixar animators wondering precisely how their cartoon critters should move. Recently a fashion design house phoned, interested in crafting haute couture fabric a customer could sculpt to the curves of her body and simply peel off. And the president of a men’s hair club wondered if it were possible to create a toupee adhesive that could withstand gale-force winds. They call because Full and his colleagues spend their time investigating how plants and animals solve similar problems and how to borrow a bit from nature’s nearly 4 billion years of research and development.

Increasingly engineers, architects, psychologists, and computer scientists are teaming with biologists to pursue what Full calls “bio-inspiration” and others tag with a trendier name, “biomimicry.” Whatever you call it, it is yielding some of the world’s quirkiest and most creatively cutting-edge inventions. The opening of a new campus lab devoted to such research solidifies Berkeley’s place among a handful of universities at the forefront of the field.

Following bio-inspiration, for example, Cal researchers are crafting a superior anti-sliding adhesive patterned after the teensy toe hairs of the gravity-defying gecko. This lizard is blessed with an uncanny ability to scamper up slick walls and dangle from ceilings by a single toe—and it can continue to do so underwater.

It isn’t suction or sticky toe jam that enables such gymnastics. Electron microscope inspection reveals that the gecko possesses about half a million bristles on each foot, terminating in a horrid case of split ends: hundreds of spatulae per bristle. This natural design gives a single gecko about a billion points of contact, maximizing a molecular phenomenon called van der Waals force—the same minuscule pull that sticks molecules together, and keeps, for example, water from spilling all over the place.

By replicating key features of the gecko’s toes, as identified by Full and Kellar Autumn (who is now a professor at Lewis and Clark College), Berkeley electrical engineering professor Ron Fearing and his team are producing a new generation of microfiber adhesives that attach with incredible force, yet detach with ease. These adhesives could be used for automobile tires with unprecedented traction, bandages that could be applied directly over burns and lift off ouchlessly, or robots that can climb up slick walls. They could revolutionize soccer by creating the greatest goalie gloves—and perhaps even produce human climbing gear. Not to mention enabling clingy designer gowns and the toughest toupee glue ever known to man.

Gecko adhesive is just one of several bio-inspiration projects underway. Researchers are replicating the locomotive abilities of insects, fish, and crabs to design and build flying and swimming robots for rescue and reconnaissance missions. Mechanical engineering graduate Marcus Rosenthal, whose bio-inspiration studies led him to co-found the company Artificial Muscle, is borrowing from nature to construct, among many other things, small, portable infusion pumps that could replace IVs, happily shortening hospital stays.

In fact, the world is percolating with bio-inspiration. Sto markets a water-repellent and self-cleaning exterior paint that mimics the incredibly rough microstructure of the seemingly smooth lotus—renowned for its ability to remain pristine in the muddiest water. Volvo developed an anti-collision system modeled on how locusts swarm without smashing into each other. Cambridge Biostability devised a method of storing vaccines in Third World locales that mimics the resurrection fern, eliminating the need for refrigeration and for booster shots.

With as many as 50 million species from which to borrow, the possibilities are enormous. Could a Namibian desert beetle with an astounding capability to convert fog into drinking water help scientists end drought? Could the strong structure of abalone shells teach us how to fashion ceramics that are unbreakable?

Red seaweed avoids bacterial invasion by cleverly releasing a chemical that plugs bacteria receptors so they never receive the message to join the invasion on a potential seaweed host. Could humans somehow mimic this strategy to repel bacteria, without deploying the arsenal of antibiotics now contributing to the rise of resistant, and deadly, super-bacteria?

“If you can conceive a design problem, chances are nature’s already solved it somewhere,” said Janine Benyus, author of the landmark 1997 book Biomimicry: Innovation Inspired by Nature and president of the nonprofit Biomimicry Institute. Benyus is the Billy Graham of biomimicry, evangelizing science and industry with the gospel that we can save ourselves and our planet only by learning to echo nature.

The premise is hardly novel. Renaissance man Leonardo da Vinci once insisted, “Those who are inspired by a model other than nature, a mistress above all masters, are laboring in vain.” But until recently, bio-mimicry’s success stories were sheer strokes of lucky happenstance. The most celebrated case in point: Velcro.

One portentous day in the 1940s, Swiss inventor Georges de Mestral trekked home from hunting in the Jura mountains and set about clawing pesky burrs out of his dog’s fur and his own wool socks when he suddenly paused to ponder the intricacy of their design. Ruefully recalling the many occasions he had been forced to fiddle with the zippers and hook-and-eye attachments on the back of his wife’s dresses, it occurred to de Mestral that nature had a better idea. His synthetic imitation, named for an amalgam of velours and crochet, hit the market in 1955 and revolutionized dressing.

Today’s aim is to make bio-inspiration not merely serendipity, but methodology. Nonetheless it all originates with plain old-fashioned curiosity. “Great inspiration begins when we look at an animal or plant being its wonderful self, and we ask ‘How the heck does it do that?’” says Full, a jolly scientist who manages to come across as both boyish and brilliant. Asking him a biological question is like uncorking champagne—he bubbles over with ebullience, his eyes popping and his arms swinging wildly as he translates complex nanotechnology into the stuff of science fiction. His campus office and lab overflow with a menagerie of creatures and the tools with which he studies them: treadmills for cockroaches, wind tunnels for hummingbirds, glass climbing walls for the geckos, and so on. There are Zoobs (nucleotide-shaped snap toys) from which students fashion designs, Jell-O used to measure the force of insect legs sprinting across a surface (flavorless, because the roaches kept stopping to nibble the orange flavor), and models of the characters Full’s expertise helped animate in the film A Bug’s Life.

The professor almost left Berkeley when Princeton made him a tempting offer, but Berkeley topped it by letting him establish a new center devoted exclusively to bio-inspiration. Thus the ground floor of the Valley Life Sciences Building has become home to the new Center for Interdisciplinary Bio-inspiration in Education and Research (CIBER), co-founded by fellow integrative biology professors Mimi Koehl and Robert Dudley. The center, which can only survive if it secures continued funding, aims to tear down the academic silos that separate knowledge by departments—integrating the fields of biology, engineering, computer science, psychology, and math.

“Oh, and I also asked the administration if I could teach more courses. Given how many researchers try like crazy to get out of teaching, their initial reaction was along the lines of ‘You want to do what?’” chuckles Full, a recipient of Berkeley’s Distinguished Teaching Award. “The best teaching has to be done at major research institutions,” he says during a stroll around his lab. “My idea is that we stop treating students like file cabinets to stuff information into, and start getting them involved as researchers. Often the undergrads are the best: They don’t know what they aren’t supposed to be able to do, so they find a way to just do it.”

This past spring marked the successful trial run of Full’s new bio-inspiration class, with students selected from an array of backgrounds and placed in four-person design teams. He also hosts bio-inventors’ nights. “Inevitably the group that wins is not the five geeky white-guy engineering majors,” he says. “It’s someone who grew up on a farm, and the art history major who’s a master of origami, maybe an engineering major, and a biology major thrown in for good measure. It’s a microcosm that proves diversity is a competitive advantage.”

Not that students bridge their divides automatically. “There’s a hump we had to get over because our fields speak different languages,” says Aaron Hoover, a mechanical engineering graduate student. “I was saying ‘Look at the cockroach’s foot’ and the biologists were saying ‘Look at its tarsi’ and I didn’t have a clue that we were really saying the same thing.”

To his utter glee, several of Full’s students have co-authored published research papers and helped make breakthrough discoveries: Hummingbirds can fly backwards at a speed of four meters per second and geckos use their tails like a bike’s kickstand to right themselves when their balance goes off kilter. “I was very excited each time we discovered something in the lab that no one had previously published—and that happened nearly every other week,” says recent integrative biology grad Talia Moore.

 

One of the most promising applications for biomimicry is the concoction of robots. The U.S. military and civilian rescuers are forever on the lookout for a better robot, which they want to dispatch on surveillance or search missions in spots too dull or too dangerous for humans.

Picture a flaming building 30 stories tall with 30 apartments per floor. Rescuers now send firefighters up to ensure everyone has evacuated. But someday that could be done by robo-flies outfitted with chemical sensor “noses” detecting carbon dioxide exhaled by survivors and miniature microphones capable of intercepting screams or even heartbeats. Fearing, who specializes in such MFIs (mechanical flying insects), has sought to mimic the aerodynamic mechanisms of bees and blowflies, whose wings flutter at 150 beats per second, to develop an agile flyer weighing as little as one-tenth of a gram.

Think of any maneuverable animal and chances are somebody somewhere is trying to replicate its skills. At Berkeley alone, researchers and their students are designing robots modeled after ghost crabs, cockroaches, fish, salamanders, lizards, and just about any creepy-crawly imaginable. The goal is never to copy an entire creature in all its glorious complexity—rather it is to co-opt its most valuable assets while simplifying everything else.

It was that guiding axiom that led Naomi Davidson and Nico Julian to develop CaliBot—the most naturally swimming robotic fish ever built. Its beauty was its simplicity. Full’s description of his daughter’s rubbery toy fish set their minds spinning. “We capitalized on the inherent property of a fish, mimicking its under-controlled, more passive approach to locomotion. And the membrane was critical to holding everything together and giving us the hydrodynamics we were looking for,” Davidson explains.

Other students constructed elaborately over-engineered devices with up to 26 motors, that couldn’t even be placed in water. The robotic fish Davidson and Julian put together had just one, a hobby motor they bought off the Internet for $10. But when they plopped it into the fountain on campus, it swam with speed and ease. Davidson completed her master’s at MIT with a thesis exploring how the kinematics of the sunfish’s pectoral fin could improve the operation of unmanned undersea vehicles.

Even beyond robotics, most bio-inspirations spring from observations about a particular creature’s useful eccentricity. Take, for example, the jewel beetle, nicknamed “firebug.” While other sensible animals flee a forest fire, these beetles swarm toward one in pursuit of literally hot-and-heavy mating sessions. The females then lay their eggs within the smoldering bark of burned coniferous trees. To thrive, these half-inch-long beetles are like heat-seeking missiles, equipped with supersensitive infrared radiation receptors that can detect fire more than 30 miles away.

The U.S. military’s current infrared sensors are more primitive, and require costly liquid nitrogen to keep them cool until use. But bio-inspired work by researchers, including a team led by Albert Pisano, chair of Berkeley’s mechanical engineering department, may lead to simpler, smaller, and cheaper infrared sensors that have civilian applications as well, such as helping foresters detect fires sooner. The research, funded by industry and by the wildfire-prone state of California, has led to the creation of functional prototypes that are performing better than expected and could hit the market within a few years. Once it’s cost-effective, “we may someday distribute thousands of these sensors over a large area of forest, and revolutionize fire detection,” says Clint Warren, who is working on the project as he earns a Ph.D. in mechanical engineering.

“When we stare this deeply into nature’s eyes, it takes our breath away, and in a good way, it bursts our bubble,” Benyus has written. “We realize that all our inventions have already appeared in nature in a more elegant form and at a lot less cost to the planet. Our most clever architectural struts and beams are already featured in lily pads and bamboo stems. Our central heating and air-conditioning are bested by the termite tower’s steady 86° F. Our most stealthy radar is hard of hearing compared to the bat’s multi-frequency transmission. And our new ‘smart materials’ can’t hold a candle to the dolphin’s skin or the butterfly’s proboscis.” In fact, Benyus reverentially refers to nature as our “hand out of the abyss.”

Nonetheless, some of Cal’s top bio-inspiration researchers blanch at the very term biomimicry, which they regard as simplistic and misleading. They argue that merely mimicking nature is a fool’s errand, rather like pasting bird feathers on a Honda and expecting it to fly. In fact, many aviation pioneers did construct devices designed to replicate flapping bird wings—none were successful, and some died trying. The Wright brothers succeeded by borrowing a single, yet complicated, concept: airfoil cross-section.

“The best ideas don’t actually just mimic nature—they borrow ideas from nature and improve upon them to produce something better than nature,” says Full. He loves to show audiences a slide of a bird of paradise and ask them to speculate about why it developed such splendid plumage. It fools engineers—they always figure the feathers enhance flying, when really their function is to attract a mate. His point: There is a poetic complexity to every species, and it is very difficult to disentangle from among these myriad functions precisely the one useful to any given human endeavor.

Nor does evolution produce the best possible designs. To the contrary, it settles for a design that is “just good enough” to survive.

A final caveat: For all its catchy appeal, bio-inspiration sometimes bombs in the marketplace. Nike, for example, produced a running shoe modeled after the sturdy feet of mountain goats, but dropped its Goat Tek line within a single season after customers showed anemic interest in goatlike footwear. Several biotech companies on a mission to artificially replicate the eerie steel-like strength of gossamer spider silk, have gone broke.

The commercial fate of gecko glue is still unknown. Fearing has won approval for seven patents, but he isn’t sure when or in what form the first gecko-based adhesive will come to market. Surfboards? Drywall? Dentures? Says Fearing, “It’s just mind-boggling how many places this could be used, but I couldn’t really venture a solid guess on what is most likely to take off.”

It’s no accident that advocates like Benyus, armed with industry investment analyses of biomimicry projects, seek to turn CEOs into converts. Her next book, Nature’s 100 Best: World-Changing Innovations Inspired by Nature, will catalogue prime examples of bio-inspiration such as gecko adhesive culled from some 2,000 nominees. Nor is it coincidental that the book will highlight potential solutions from several organisms that experts fear could wind up extinct. “I’ve talked to Al Gore about this,” says Full. “Yes, polar bears are cute and we should save them for all that. But if for no other reason, we ought to save endangered species for selfish reasons. If we destroy them, their secrets are lost to us forever.”

From the November December 2008 Stars of Berkeley issue of California.
Filed under: Science + Health
Image source: Illustration by Jon Reinfurt
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