Paved roads are nice to look at, but they’re easily damaged and costly to repair. UV rays, weather, oxidation and constant traffic wear down paved surfaces, loosening rocks and creating dangerous potholes.
But are there better alternatives for paving roads than traditional asphalt? At TEDxDelft, civil engineer Erik Schlangen says yes. Here he demonstrates a new type of porous asphalt with an astonishing feature: When cracked, it can be “healed” by induction heating.
This “self-healing” asphalt is infused with tiny strands of steel wool (yes, that steel wool — the same used to scrub dishes), which clings to the binding of the asphalt, called bitumen. When Schlangen’s asphalt develops a crack, caretakers can use heat to melt the steel mixed in the bitumen, which then liquifies and flows into the road’s cracks, “healing” itself.
Onstage, Erik demonstrates this process by dropping a piece of his asphalt into liquid nitrogen, breaking it, and then heating it in a microwave to “heal it,” a process from which the asphalt reemerges fully formed. Out on the roadways, he and his team from the Delft University of Technology are working on a real piece of highway donated by the Dutch government, 400 meters of the A58, where they’ve discovered that this process really works, as Erik says in his talk:
“If we go on the road every four years with our healing machine — this is the big version we have made to go on the real road — if we go on the road every four years, we can double the surface life of this road, which of course saves a lot of money.”
Erik is also working with microbiologist Henk Jonkers to create a “self-healing” building concrete (pictured above, on bottom), which is infused with bacterial spores and a compound that feeds these spores — calcium lactate. “When the biomaterial is exposed to water (one of the many things known to contribute to the degradation of concrete),” says io9, “the bacteria set to work converting calcium lactate into calcite, which fills in surrounding cracks.”
We can’t wait to see what comes of these exciting new building materials, and until then, we’re crossing our fingers for self-healing smartphone screens.
(Bio-concrete photo via io9)
Spotlight on the Netherlands: 5 engineering talks from the Low Country
Home to a thriving tech and science community, The Netherlands has a lot to offer when it comes to groundbreaking TEDx Talks. But today, we offer just a small tasting — 5 uber-brainy TEDx Talks highlighting some of the exciting new projects underway in the land of tulips.
A robotic revolution for eye surgery: Maarten Beelen at TEDxBinnenhof
The eye is one of the most delicate structures in the body, and eye surgery can prove very risky for all but the steadiest of hands. Maarten Beelen introduces a new breed of robotic technology that may one day make surgical procedures on the eye easier and safer.
Portable water drilling for the remotest areas: Floris de Vos at TEDxBinnenhof
One day, Floris de Vos, a former drill rig operator, had an epiphany that has the potential to bring fresh water to people living in the most remote areas in the world. Using his human-powered water pump, nicknamed the “Flo-flo”, a well can be drilled almost anywhere, even in the rockiest of soil.
Finally, kites have grown up: Roland Schmehl at TEDxDelft
Wind power is a fast-growing alternative energy source, but traditional wind turbines are noisy, cumbersome, and pose a danger to wildlife. In this talk, Roland Schmel proposes a surprising solution: turning the simple kite into a power generator.
Indoor farming: A plant paradise: Gertjan Meeuws at TEDxBrainport
For centuries, prevailing wisdom has held that plants are happiest when they grow naturally. That’s not true, says Gertjan Meeuws. Using specially-designed indoor greenhouses, scientists can help plants grow much more efficiently. As an added bonus, land, pesticide and water usage are greatly reduced and crops reach consumers fresher and faster.
Mobile power for mobile devices: Marijn Berk at TEDxRotterdam
While the devices that we use for communication and entertainment are now mobile, the power sources that they use are not. Marijn Berk proposes using new materials that generate power from sunlight to keep mobile devices moving.
Photos: The Laddermill team testing their new power-kites. See a full video here.
Want renewable power? Go fly a kite.
“Today, wind turbines are the cornerstones for the transition from fossil fuels to renewable energy provision,” says Roland Schmehl in his talk at TEDxDelft in the Netherlands. But they are not without their problems, he admits. There’s the threat to wildlife, the noise, the lack of mobility.
So, he’s proposed a solution: kites.
Above: Roland’s talk — “Finally, kites have grown up.”
As a member of the Applied Sustainable Science, Engineering and Technology (ASSET) Institute at Delft University of Technology, he is a part of the Laddermill project — an effort to create giant kites that serpentine the sky to collect kilowatts of power in the double digits, if not more.
A prototype of the Laddermill collected 10 kilowatts of power on a test run, “enough electricity to power 10 family homes,” according to The Guardian, and it has been predicted that a collection of Laddermill kites could possibly capture 100 megawatts of power — enough to power 100,000 homes.
“The bigger you build a [tower-based wind] turbine,” Roland says in his talk, “the more efficient you can make it… the higher you reach with the turbines, the higher the energy density that you can harvest. But there is obviously a limit. Although we’ve built turbines that are approaching the wingspan of an Airbus 380 — there is a limit. It is a structural limit. We simply cannot build tower-based turbines that can actually reach into several hundred meter altitudes.”
This is where the kite comes in:
“The [tip], the last 25% of [a wind turbine] rotor blade actually makes more than 50% of the energy,” he says. “So why don’t we decouple the rotor blade from the hub and actually move it — as a free-flying wing — into the air?”
“The kite system can adapt itself to the altitude where the actual wind power is — so if there is little wind at the ground, we just fly higher, where the wind is typically stronger. If the wind is too strong, we can go lower again…
We put the generator onto the ground; we connect that with a very strong and lightweight tether, which actually converts the traction force of the wing — transmits that to the generator — to convert to electricity.
[And] it can be used, for example, for remote applications: development areas, disaster areas, all these places where you need energy quickly and you don’t have oil — or fuel.”
So, the next time you go to fly a kite, remember its power — and watch more TEDxDelft talks via their YouTube playlist.
Above: Callum Cooper’s film explaining TEDxUtrecht speaker Massoud Hassan’s mine-detonating, rolling super-toy, the Mine Kafon.
Massoud Hassani is the creator is the Mine Kafon, a tumbleweed-like apparatus that uses wind gusts to roam through land mine filled areas and detonate hidden mines as it goes. Born from designs of the wind-powered toys Massoud and his brother sent tumbling in the desert outside of Kabul as children, the Mine Kafon almost looks like a toy itself — a giant mass of poles and suction cups, made from bamboo and biodegradable plastics.
During his talk at TEDxUtrecht in The Netherlands, Massoud explained his process behind designing the prototype, something he hopes will soon turn into an affordable alternative to the very expensive land mine clearing methods of today:
I was born in Afghanistan…[In school], usually you get math, languages, and so on, but we got classes about land mines — so I know all of them. I know how to open them, because every day [they were] on our playground.
…We have to do something about it…but for now it’s really commercial companies [clearing them] — and they want to keep it like that, because they are earning money. They are [employing] not really trained people — just locals — and the locals, they want to earn money, [so] they are taking the risk to clear the land mines.
The time you have to invest to find a land mine — it takes days. [So] I went back to my childhood and made a few toys… I enlarged one of the ones that we were playing with on the ground in Afghanistan, and I thought, ‘Okay, if you make it bigger…it will become stronger as well, and heavier, and now if it runs over a land mine, it’s heavy enough to detonate it — because it has the same weight of a foot.’
..So I built it.
Currently, Massoud is raising the funds to build a better prototype, with hopes that the Mine Kafon will soon be available to clear mines in his home country and across the world. Until then, you can read more about the project on his Kickstarter page.
