While robots have long been invaluable when it comes to doing all sorts of heavy lifting, they lack a gentle touch. Hefting around auto parts is easy enough, but transporting eggs or glassware poses a significant challenge.
Scientists have now, however, made a flexible plastic robot tentacle that can, among other dexterities, pick flowers without crushing them, the latest of several robot appendages made of softer materials and able to accomplish delicate tasks.
The researchers control the tentacle by pumping air through three separate channels, giving it a wide range of motion and letting it reconfigure to grasp a variety of objects without being limited by the shape of its grip. The parts for the bot—mostly elastomer tubing—cost less than $10, far cheaper than the complex components of many far less flexible robotic hands.
If you’ve ever investigated how a microwave warms up your food, then you already know that the box fills with electromagnetic waves, which vibrate water molecules to create friction and heat. But how does the microwave’s magnetron (an energy-generating vacuum tube) produce those waves in the first place—and how can you measure them using cheese? The Engineer Guy, also known as University of Illinois at Urbana-Champaign professor Bill Hammack, has all the answers in this enlightening video.
As I watch the graduates parading proudly around my Brooklyn neighborhood, I’ve been thinking a lot about how we handle high-school education in this country. When I attended high school in suburban Maryland, engineering wasn’t considered a subject. We had English, all the sciences, math, music, social studies, even home ec, but engineering was absent. And no, this isn’t one of those “my how times have changed since I was young” stories. Things haven’t changed, at least by much; and that’s not good, given the challenges that lie ahead.
My thoughts are inspired in part by the DiscoverE Summit, sponsored by ASME, the American Society of Mechanical Engineers, the National Engineers Week Foundation, and DISCOVER magazine. Back in February I had the pleasure of joining three outstanding K-12 educators from across the country—Javaris Powell, Shella Condino, and Derek Sale—as they were celebrated for their commitment to STEM education (science, technology, engineering, math) and for the extraordinary impact they’ve had on their students.
Javaris, Derek, and Shella all teach in underserved communities. But lack of money and supplies isn’t their most troubling problem. Javaris told me that the most difficult part of his job is breaking through his students’ own stereotypes:
What’s something that everyone hates? That’s the question that undergrads at Case Western University asked recently while brainstorming their entry for a materials science competition. Their answer: potholes. And their answer to the problem of how to fill them cheaply and easily? Basically, corn starch and water.
It’s not as strange as it sounds: the corn starch putty is a non-Newtonian fluid, a class of fluids that behave very differently from water. In the case of the putty, when it’s placed in an oddly shaped receptacle, like a pothole, it will flow like a liquid into all the nooks and crannies. But the second you push on it, with a car, for instance (or, as you can see in the above video, your feet), it turns solid, resisting compression and giving drivers a smooth ride.
Metamaterials—materials engineered to have optical, thermal, or other specific properties naturally occurring substances don’t—can block, bend, and otherwise manipulate all sorts of waves: they can, at least in theory, twist light to render objects invisible, contort ultrasound waves to hide things from sonar, and disguise the telltale wake of a submarine. Now, in an arXiv paper, Australian and Korean researchers have suggested another wave-altering use for metamaterials: protecting buildings from earthquakes’ powerful seismic waves.
One cable holds the bridge up.
San Francisco has its share of massive earthquakes, but the Bay Bridge, one of the city’s main transit arteries, is not as quake-safe as you’d hope. That’s why, alongside it, the state is building a massive new replacement structure—the largest self-supporting suspension bridge ever built. Jim Giles at New Scientist went to visit the bridge and provides a primer on its engineering:
In a regular suspension bridge, the cables that support the roadway are hung between two or more towers, like a hammock between trees, and anchored at each end by a connection to land. The new bridge is more like a sling. A single cable loops under the roadway, over the tower and beneath the roadway on the other side of the tower. The enormous forces placed on the cable by the road cancel out, leaving a structure that is balanced but not directly supported by a land anchor…
As the [road] segment fell into place it revealed the full length of tower that stands behind it, an elegant structure made up of four concrete pillars. These drop into enormous steel foundations, parts of which were built in Texas and shipped to California via the Panama canal. The pillars are connected by “shear beams”—relatively weak steel components that are designed to break if the towers move. The two roadways, one each for east and westbound traffic, hang from the cables but are not attached directly to the tower. This arrangement means that the four pillars and two roadways will sway when a quake hits, but remain intact even through the strongest shaking that geologists expect the region to experience over the next 1500 years.
Read more at New Scientist.
Image courtesy of Bay Bridge Information Office.
What’s the News: Scientists have already bent light to make invisibility cloaks and manipulated sound to hide underwater objects from sonar. Now, researchers have come up with a preliminary design for a mesh shield that would let submarines stealthily maneuver through the seas without leaving any wake, they report in a study published online last week.
What’s the News: Keeping track of what’s happening inside the body often requires a great deal of equipment outside it: Just think of the tangle of sensors in any hospital room. Now, though, engineers have developed an ultra-thin electrical circuit that can be pasted onto the skin just like a temporary tattoo. Once it’s served its purpose, you can simply peel it off. These patches could be provide a simpler, less restrictive way to monitor a patient’s vital signs, or even let wearers command a computer with speech or other slight movements.
Most archaeologists dig up the past, examining artifacts for clues—but experimental archaeologists build the past from the ground up, testing out what they can make and do using the same tools and techniques ancient peoples did. Brandon Keim at Wired Science has compiled a fascinating collection of these studies, following scientists as they sail the South Pacific on rafts of balsa wood, hunt deer with flint-tipped spears, and build smoky fires to keep warm through the Scandinavian winter (above).
[See the rest at Wired Science.]
Scanning electron micrograph images of the nut (A,B)
and screw (C, D) in the leg joint of a Papuan weevil
What’s the News: Biologists spend lots of time poring over nature’s nuts and bolts. Now, for the first time, they’ve found a biological screw and nut—previously thought to be an exclusively human invention. The legs of beetles called Papuan weevils, researchers report today in Science, have a joint that screws together much like something you’d find in the hardware store.