Monthly Archives: October 2016

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The Magnetic Robot Swarms Could Combat Disease

Magnetically controlled swarms of microscopic robots might one day help fight cancer inside the body, new research suggests.

Over the past decade, scientists have shown they can manipulatemagnetic forces to guide medical devices within the human body, as these fields can apply forces to remotely control objects. For instance, prior work used magnetic fields to maneuver a catheter inside the heart and steer video capsules in the gut.

Previous research also used magnetic fields to simultaneously control swarms of tiny magnets. In principle, these objects could work together on large problems such as fighting cancers. However, individually guiding members of a team of microscopic devices so that each moves in its own direction and at its own speed remains a challenge. This is because identical magnetic items under the control of the same magnetic field usually behave identically to each other.

Now, scientists have developed a way to magnetically control each member of a swarm of magnetic devices to perform specific, unique tasks, researchers in the new study said.

“Our method may enable complex manipulations inside the human body,” said study lead author Jürgen Rahmer, a physicist at Philips Innovative Technologies in Hamburg, Germany.

First, the scientists created a number of tiny identical magnetic screws. The researchers next used a strong, uniform magnetic field to freeze groups of these magnetic screws in place. In small, weak spots within this powerful magnetic field, the microscopic screws are free to move. Superimposing a relatively weak rotating magnetic field could make these free screws spin, the researchers said.

In experiments, the researchers could make several magnetic screws whirl in different directions at the same time with pinpoint accuracy. In principle, the scientists noted, they could manipulate hundreds of microscopic robots at once.First, the scientists created a number of tiny identical magnetic screws. The researchers next used a strong, uniform magnetic field to freeze groups of these magnetic screws in place. In small, weak spots within this powerful magnetic field, the microscopic screws are free to move. Superimposing a relatively weak rotating magnetic field could make these free screws spin, the researchers said.

“One could think of screw-driven mechanisms that perform tasks inside the human body without the need for batteries or motors,” Rahmer told Live Science.

One application for these magnetic swarms could involve magnetic screws embedded within injectable microscopic pills. Doctors could use magnetic fields to make certain screws spin to open the pills, the researchers said. This could help doctors make sure that cancer-killing radioactive “seeds” within the pills  target and damage only tumors rather than healthy tissues, cutting down on harmful side effects, the researchers said. Once the pills deliver a therapeutic dose of radiation, physicians could then use magnets to essentially switch the pills off. (The pills would be made of metallic material that would otherwise keep radiation from leaking out.)

Another potential application could be medical implants that change over time, the researchers said. For instance, as people heal, magnetic fields could help alter the shape of implants to better adjust to the bodies of patients, Rahmer said.

In the future, researchers could develop compact and magnetic field applicators to control tiny magnetic robots, and use imaging technologies such as X-ray machines or ultrasound scanners to show where those devices are located in the body, Rahmer suggested.

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This Robo-Bees Could Aid Insects with Pollination Duties

Mini drones sporting horsehair coated in a sticky gel could one day take the pressure off beleaguered bee populations by transporting pollen from plant to plant, researchers said.

Roughly three-quarters of the world’s flowering plants and about 35 percent of the world’s food crops depend on animals to pollinate them, according to the U.S. Department of Agriculture.

Some of nature’s most prolific pollinators are bees, but bee populations are declining around the world, and last month, the U.S. Fish and Wildlife Service listed a native species as endangered for the first time.

Now, researchers from Japan said they’ve taken the first steps toward creating robots that could help pick up the slack from insect pollinators. The scientists created a sticky gel that lets a $100 matchbox-size dronepick up pollen from one flower and deposit it onto another to help the plants reproduce.

“This is a proof of concept — there’s nothing compared to this. It’s a totally first-time demonstration,” said study leader Eijiro Miyako, a chemist at the National Institute of Advanced Industrial Science in Tsukuba, Japan. “Some robots are expected to be used for experiments in pollination, but no one has tried yet.”

The key innovation of the new study, published today (Feb. 9) in thejournal Chem, is the so-called ionic liquid gel, but according to Miyako it was more down to luck than design. The gel was actually the result of a failed attempt to create electrically conducting liquids and had sat forgotten in a desk drawer for nearly a decade.

But after eight years, it still hadn’t dried out, which most other gels would have done, and was still very sticky, Miyako said. Fortunately, this discovery coincided with Miyako watching a documentary that detailed concerns about insect pollinators.

 “I actually dropped the gel on the floor and I noticed it absorbed a lot of dust, and everything linked together in my mind,” he told Live Science.

The gel has just the right stickiness, meaning it can pick up pollen but is not so adhesive that it won’t let the grains go.

The scientists next tested how effectively the gel could be used to transport pollen among flowers. To do so, the researchers put droplets of the material on the back of ants and left the insects overnight in a box full of tulips. The next day, the scientists found that the ants with the gel had picked up far more pollen grains than those insects that lacked the sticky substance.

In a side experiment, the researchers found that it was possible to integrate photochromic compounds, which change color when exposed to UV or white light, into the gel. Scientists stuck this material onto living flies, giving the bugs color-changing capabilities. This, Miyako said, could ultimately act as some kind of adaptive camouflage to protect pollinators from predators.

But while improving the ability of other insects to pollinate flowers is a potential solution to falling bee numbers, Miyako said he was not convinced, and so began to look elsewhere. “It’s very difficult using living organisms for real practical realizations, so I decided to change my approach and use robots,” he said.

The hairs that make insects like bees fuzzy are important for their role as pollinators, because the hairs increase the surface area of the bees’ bodies, giving pollen more material to stick to. In order to give the smooth, plastic drone similar capabilities, the scientists added a patch of horsehair to the robot’s underside, which was then coated with the gel.

The researchers then flew the drones to collect pollen from the flowers of Japanese lilies and transport this pollen to other flowers. In each experiment, the researchers made 100 attempts at pollinating the flower, achieving an overall success rate of 37 percent. Drones without the patch of hair, or with uncoated hair, failed to pollinate the plants.

Miyako said there are currently limitations to the technology, because it is difficult to manually pilot the drone. However, he added that he thinks GPS and artificial intelligence could one day be used to automatically guide robotic pollinators.

Before these robo-bees become a reality, though, the cost of the drone will have to come down drastically and it’s 3-minute battery life will need to improve significantly, Miyako said. But he added that he is confident this will happen eventually.

Dave Goulson, a professor at the University of Sussex in the United Kingdom, said he sees the intellectual interest in trying to create robot bees, but he’s skeptical  about how practical they are and worries about distracting from more vital pollinator conservation work.Goulson specializes in the conservation of bumblebees but was not involved with the new research.

In a blog post, he wrote that there are roughly 3.2 trillion bees on the planet. Even if the robo-bees cost 1 cent per unit and lasted a year, which he said is a highly optimistic estimate, it would cost $32 billion a year to maintain the population and would litter the countryside with tiny robots.

“Real bees avoid all of these issues; they are self-replicating, self-powering and essentially carbon-neutral,” Goulson wrote in the post. “We have wonderfully efficient pollinators already. Let’s look after them, not plan for their demise.”

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North Korea’s Missile Will Threats to US

North Korea has always talked the talk, and now it seems to be walking the walk as never before.

The nuclear-armed rogue nation appears to be making progress on anintercontinental ballistic missile (ICBM), which could conceivably allow the Hermit Kingdom to make good on its oft-repeated threat to turn major American cities into “seas of fire,” experts say.

“They’ve probably reached the point where they’re going to need to start testing the missiles themselves — the whole system,” said Joel Wit, senior fellow at the U.S.-Korea Institute (USKI) at Johns Hopkins University’s School of Advanced International Studies. “Most people think that could come sometime this year.”

Last year’s successful test-launch of a missile from a submarine suggests that a mobile-strike capability may be within North Korea’s grasp soon as well, analysts have said.

The North Korean missile program got its start with the importation of Soviet Scuds, which made their way into the nation in the 1970s. North Korea reworked Scud technology into a number of variants over the years, apparently with the help of Soviet engineers (many of whom fled the USSR after its 1991 collapse).

These versions include the Hwasong-5 and Hwasong-6, which are thought to have a range of a few hundred miles, and the Nodong, which experts believe can reach targets 620 miles to 800 miles (1,000 to 1,300 kilometers) away. (It’s hard to know anything for sure about North Korea’s missiles and rockets, because the nation’s government is extremely secretive and works to keep much information from getting to the outside world.)

North Korea has also developed longer-range missiles, including the Taepodong-1, Musudan and Taepodong-2, which have estimated maximum ranges of about 1,500 miles (2,500 km), 2,000 miles (3,200 km) and 3,000 miles to 5,400 miles (5,000 to 9,000 km), respectively.

Taepodong-1 has just one known flight under its belt. In April 1998, a modified space-launch configuration of the vehicle lifted off with a small satellite onboard; Western observers concluded that the launch failed.

The Taepodong-2 failed during a 2006 test flight, its only known liftoff. However, North Korea modified the missile into the Unha space launcher, which lofted satellites to orbit in December 2012 and February 2016.

The Musudan has seen a lot more action. North Korea apparently tested the medium-range missile seven times last year, with just one success, said physicist and missile-technology expert David Wright, co-director of the Union of Concerned Scientists’ Global Security Program.

Such flights flout United Nations resolutions, which prohibit North Korea from testing missiles and nuclear weapons. Pyongyang has also conducted five known nuclear tests, with the latest one coming in September 2016. [North Korea Looks Strangely Dark From Space In Asia Fly-Over (Video)]

North Korea could conceivably combine several of these existing vehicles to build an ICBM, topping an Unha first stage with a second stage based on the Musudan and adding a third stage of some sort, Wright said. But there’s no evidence that the nation is actually doing that, he added.

“North Korea is probably reluctant to turn the Unha into a ballistic missile, because I think they want something that really is a civil space-launch program that they can point to and say, ‘This is what countries do. We’re launching satellites; it’s not a threat,'” Wright told Space.com. “So my guess is, they won’t go that route.”

The route that Pyongyang appears to be taking instead, experts say, centers on a missile called the KN-08, a likely Russian-derived vehicle that Western observers first spotted in North Korean military parades about five years ago.

“It is much better suited as a militarily effective ICBM than the Unha is,” Brian Weeden, a technical adviser for the nonprofit Secure World Foundation, told Space.com. He noted, for example, that the KN-08 can be launched from a truck, whereas the Unha requires a stationary facility.

Work on the KN-08 has apparently been proceeding apace. For instance, in April 2016, Pyongyang ground-tested a large, liquid-fueled engine that could power the putative ICBM and/or a more muscular variant known as the KN-14.

“Using this technology, North Korea’s road-mobile intercontinental ballistic missile (ICBM), the KN-08 or the KN-14 modification, could deliver a nuclear warhead to targets at a distance of 10,000 to 13,000 kilometers [6,200 to 8,000 miles],” aerospace engineer and rocket-propulsion expert John Schilling wrote on 38North.org, a North Korea analysis site, shortly after the test.

“That range, greater than had previously been expected, could allow Pyongyang to reach targets on the U.S. East Coast, including New York or Washington, D.C.,” he added.

And North Korea has also been working on a re-entry vehicle, which would protect the warhead during the ICBM’s return to Earth’s atmosphere from suborbital space. Last year, North Korean leader Kim Jong-un held an event during which he stood next to a re-entry vehicle, said Wit, who is also the co-founder of 38 North (a USKI program).

“I think you can be almost 100 percent certain that they’ve done [re-entry vehicle] tests on the ground,” Wit told Space.com.

During a speech on New Year’s Day, Kim announced that Pyongyang was in final preparations to test-launch its ICBM. Wit said such a flight could come soon — possibly as early as next month, when the U.S. and South Korea hold their annual joint military exercises.

“That could trigger a North Korean response,” Wit said.

If ICBM testing does indeed start this year, the missiles could potentially be ready for deployment by late 2019, he added.

Pyongyang also conducted a successful test launch from a submarine in August 2016, sending one of its KN-11 (also known as Pukguksong-2) missiles about 300 miles (500 km) toward Japan. Developing this technology to the fullest extent would make North Korea more dangerous and capable, Wright said.

“That’s another thing that people are watching — this combination of a missile and a submarine,” he said.

The missile that North Korea fired on Sunday (Feb. 12), which traveled 300 miles (500 km) before splashing down in the Sea of Japan, was a land-based version of the KN-11, according to the North Korean news service.

North Korea is famously unpredictable, secretive and prone to outbursts of grandiose and threatening rhetoric; Kim and other officials have repeatedly vowed to wipe out South Korea, Japan and the United States, for example.

But Pyongyang’s development of a functional ICBM, if and when that does indeed happen, shouldn’t incite panic across the United States, experts said. After all, North Korea has been capable of hitting South Korea and Japan for a while but has yet to do so — probably because the nation knows that such an unprovoked strike would be suicidal, drawing a devastating response from the U.S.

And the Kim regime is not suicidal; rather, it appears focused primarily on strengthening and perpetuating its rule, Weeden said.

“It’s very clear that they want to send a signal to the West that they can’t be messed with,” he said. “There’s a rationality there.”

There are other reasons to doubt that North Korea will launch a nuclear ICBM attack on the U.S. anytime soon.

For example, Pyongyang is thought to possess just a handful of nuclear weapons. A 2015 SAIS report co-authored by Wit pegged the nation’s stockpile at 10 to 16 nukes. By 2020, this number could grow to 20 in a “best-case scenario,” and to 100 in a “worst-case scenario,” the report predicted.

Each warhead is therefore quite valuable to North Korea, Wright said — meaning the nation probably won’t use its nukes lightly.

“It might be the kind of thing you would like to have in your back pocket, to make people think, ‘Well, gee, maybe in a bad situation, they might try a Hail Mary pass and see whether it works,'” Wright said. “But it’s not the sort of thing that you’re going to be able to rely on other than that.”

That’s not to suggest that North Korea is all bluster, however.

“I think the best bet is that they would use nuclear weapons if they felt the regime was threatened in a serious way,” Wit said. “Of course, the main way that might happen is if there’s a war on the Korean Peninsula, and U.S. and South Korean troops are moving north.”

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This 3D Printed Micro Camera Sees with Eagle Eye Vision

A bird of prey on the hunt must be able to clearly see faraway objects while remaining aware of threats in its peripheral vision. In some cases, that’s also true for a drone — even one so small that its eye must fit on the tip of a ballpoint pen. Now, a team of engineers has developed a camera that could provide eagle-eye vision to micro-drones.

The new camera could be used for medical procedures, such as endoscopies, or to build micro-robots specially designed to measure, explore or survey, the researchers said.

Previously, the engineers used a technique called femtosecond laser writing to 3D-print miniature lenses directly onto an image-sensing chip. To create sharp images like an eagle’s eye, the researchers used this process to print clusters of four lenses at a time. The lenses range from wide to narrow and low to high resolution, and images can then be combined into a bull’s-eye shape with a sharp image at the center, similar to how eagles see.

“This means that we still cover the whole object and get a better resolution in the center,” said study lead author Simon Thiele, a scientist at the Institute of Technical Optics at the University of Stuttgart in Germany. “The drawback is that we lose information in the periphery.”

The goal is to optimize the flow of information, Thiele told Live Science in an email.

The four lenses can be scaled down to a footprint as small as 300 micrometers by 300 micrometers (0.012 inches or 0.03 centimeters on each side), similar to a medium-size grain of sand. The researchers said the size of the entire camera setup could decrease with design tweaks to pack in or combine lenses, or as smaller chips become available.

In the animal kingdom, creatures must balance their visual needs and their brain power. The solution in humans and many other vertebrates is known as “foveated” vision, with the sharpest image in the center and a wide range of lower-clarity vision at the edges.

“If you had the resolution of the fovea all over your eye, you’d have to carry the visual part of your brain around in a wheelbarrow,” said Wilson Geisler, a vision scientist at the University of Texas at Austin, who was not involved in the new research.

“If you’ve got the right application, this could be a very useful technology,” Geisler told Live Science. The technology could be used in drones that face challenges similar to animals with foveated vision, with limitations on the bandwidth to send information, but the ability to control movement of the camera to focus on areas of interest, he said.

Thiele said the next step in the research will be to print a lens array on the smallest available image sensors, measuring about 0.04 square inches (1 square millimeter), with the lenses covering more of the surface of the sensor.