To get the upper hand in any scenario, the U.S. military has often relied on the most outlandish innovations the mind can conjure. Stealth technology, bionic limbs, and a little thing called the Internet all started with the military— specifically, as brainchildren of the Defense Advanced Research Projects Agency (DARPA), the 60-year-old fount of new technology in soldiering. RD reviewed the next wave of advances, looking for those destined to spread.
Spend time speaking with foot soldiers, and you’ll eventually hear about lugging an overstuffed backpack for miles in terrible weather through rough terrain. But the age‑old problem of overburdened troops is deadly serious: An army on the move can be dangerously slowed and weakened by strain injuries or just by soldiers struggling under their loads.
So the minds at DARPA threw down this gauntlet to the scientific community: Build some kind of wearable contraption that would help combatants transport their burdens. It needed to be thin and supple enough to fit under battle uniforms and equipment.
To come up with a solution, Ignacio Galiana, PhD, and his researchers at Harvard’s Wyss Institute for Biologically Inspired Engineering immersed themselves in studying a simple act we take for granted: walking. They scrutinized the leg muscles’ perfectly timed bursts of energy to understand how a walker might get a little assist. “What we learned,” says Galiana, “is that small changes in timing—just a few milliseconds—could make a difference between assisting and hindering someone.”
So Galiana and team developed a suit that is essentially a wearable robot: the Warrior Web exoskeleton. Tiny sensors embedded in the fabric take readings every millisecond or so on how the wearer is moving. The data are fed to a computer housed in a fancy fanny pack. Retractable spooling cables extend from the waist pack to the ankles. “When the system senses fatigue, the cable applies pressure to joints that mimics muscle movement, so you spend less energy moving your legs,” the Spanish-born Galiana says. “The system is learning how you’re walking and adapting the timing and parameters to make sure the assistance is maximizing the benefit you get.” The program is in its final stages; prototypes have been delivered to the Department of Defense.
And someday these suits might help civilians too. The Wyss Institute has licensed the technology to a private medical-device company to help stroke victims walk again. The invention could also give a weak or elderly person enough of a boost to power his or her way from the store to the car with a load of groceries. Check out the accidental discoveries that changed the world.
Plants that spy
Imagine an innocuous-looking field of poppies at the outskirts of a hostile foreign capital. Suddenly a surveillance drone zooming in on the field finds that all the flowers are leaning in the same direction. The poppies have been genetically engineered to bend toward the presence of sarin gas, so American analysts strongly suspect that the country is developing a poison-gas program.
Without question, the ability to detect chemical, biological, radiological, nuclear, and explosive threats is paramount to national security. But … with plants? Who comes up with these ideas? Meet Blake Bextine, PhD, a professor of biology at the University of Texas at Tyler, who heads up the Advanced Plant Technologies (APT) program at DARPA.
“The idea for APT came from conversations I had with the military. One of the needs they talked a lot about was surveillance. Existing sensors had two problems: They were made from costly metals and plastics, and they relied on batteries,” explains Bextine. “Plants get their energy from the sun, of course, and they’re infinitely scalable.”
Bextine is used to the outlandish. In 2014, he starred in the reality TV show Tethered. The concept: Two polar opposites are forced to survive in the wilderness while bound together by a six-foot cable. “I was put with a practicing shaman,” Bextine says. For 11 days, the pair climbed up and down hills, hiked over mountains and into valleys, jumped off cliffs, ran into waterfalls, and, for the most part, got along. “My way of approaching things was scientific thought; his way was to pray for things.”
Learning to work with others to overcome obstacles was good practice for his time at DARPA. “We don’t fix small problems,” he says. “We’re supposed to be doing the big ideas, future-possibility ideas, so we think a little differently than most people.”
As “different” as plant technology is, its foundation is solid: Plants are highly sensitive to what’s going on around them, making them excellent sentinels. The trick, of course, is to use genetic engineering to create varieties that will exhibit some predictable, detectable change when exposed to a threat. “Plant-modification platforms have really taken off in the last five to ten years,” says Bextine. “Science is at the right time to do this.”
APT is just getting under way, but if it’s successful, Bextine says we may see thistles that bloom two months early because there are land mines in their field. Closer to home, plants could serve as warning systems for virulent strains of flu, while streamside weeds might alert authorities to the presence of toxins in the water.
“A colleague of mine has said that at DARPA, if you don’t produce the next Internet, you get a B. As a program manager, I want to make sure I get an A, and I think APT is a program that has the possibility of doing that.” Don’t miss the most ironic inventions ever created.
It’s midnight, and a commando team needs to place a sniper on the roof of a glass-walled office building. But the enemy has all the entrances secured, and the element of surprise is crucial. Not to worry: From his pack, the sniper pulls out a lightweight kit, straps some paddles to his hands, and begins scaling the smooth, flat exterior like an exotic lizard. But not just any lizard.
“A couple years ago, my son requested a gecko for his birthday, and I have to say, I am awed by this thing,” program manager David Carter, PhD, told scoutcambridge.com. “It puts any engineering we can do to shame. It can leap and catch itself with one foot. It’s quite remarkable.”
Today, Carter and his team of engineers at Draper Laboratory in Cambridge, Massachusetts, working with DARPA, are using state-of-the-art nanotechnology methods to mimic his son’s pet. They studied the tiny hairs on the gecko’s feet that allow it to grip very smooth surfaces—such as plate glass windows—and came up with a material called MicroHold. Then they added it to paddles with suction cups to reduce slippage.
Earlier this year, British explorer Andy Torbet scaled a ten-story glass building using the lizard-like rig. “We were fairly confident we’d do well, but it was a little nerve-racking,” Carter admitted to bizjournals.com. “There was a lot of grit and grime on the windows.”
Speaking of grimy windows, MicroHold could well be the solution to safely cleaning those too. It might also help you hang pictures without marring your drywall or mount speakers on the glass wall of your sunroom.
“This is about the most fun thing an engineer can get paid to do,” says Carter. “We’ve gone from the fundamental physics of how the gecko adheres to the engineering challenge of scaling up to larger and larger size.”
Buildings that grow themselves
Sequoia seeds: DARPA program manager Justin Gallivan, PhD, is fascinated by them. Specifically, how incredible it is that a tiny seed holds all the genetic material required to shape a 300-foot-tall forest giant. So when Gallivan heard that a company called Ecovative had discovered that some mushroom cells would feed off farm waste, bind to it, and ultimately “grow” into molded packing materials and furniture parts, he had an idea. What if, instead of using the lowly mushroom, cells from the mighty sequoia could be induced to do something like that? Would it mean that, instead of trucking in lumber to a building site, you could make a structure from living materials that you grew right there?
Gallivan is not a biologist. In fact, the last biology class he took was in ninth grade. Still, as a professor of chemistry at Emory University, he could easily imagine the defense applications. The military often builds structures in remote and inhospitable parts of the world. Getting the building materials there is costly and time-consuming, and once the structures have been built, they’re subject to damage from storms, accidents, and wear and tear.
The nonmilitary possibilities of the program, known as Engineered Living Materials (ELM), are just as exciting. A hurricane will destroy thousands of homes in some corner of the globe. With ELM, humanitarian workers may well show up not with truckloads of lumber but with a set of lightweight cardboard molds and some seeds. They’ll add water and within three days have bricks, blocks, tiles, and shingles that are alive and ready to be assembled into buildings. “Could you take a seed and grow a living two-by-four reliably every single time?” Gallivan wonders. “Could you program it so if you wanted two-by-eights, you’d just use a different seed?” An even more out-there possibility: creating buildings whose “skins” heal themselves when cut by, say, a hurricane.
Gallivan hopes to have proof that ELM is viable by 2020. Next, find out the most famous invention from all 50 states.