Amazing Science

One of the biggest challenges with swarms of robots is manufacturing and deploying the swarm itself. Even if the robots are relatively small and relatively simple, you’re still dealing with a whole bunch of them, and every step in building the robots or letting them loose is multiplied over the entire number of bots in the swarm. If you’ve got more than a few robots to handle, it starts to get all kinds of tedious.

The dream for swarm robotics is to be able to do away with all of that, and just push a button and have your swarm somehow magically appear. We’re not there yet, but we’re getting close: At IROS this month, researchers from the Wyss Institute for Biologically Inspired Engineering at Harvard presented a paper demonstrating an autonomous collective robotic swarm that can be manufactured in a single flat composite sheet. On command, they’ll rip themselves apart from each other, fold themselves up into origami structures, and head off on a mission en masse.

The process works like this: There are four robots in this sheet, and they’re pretty darn near two dimensional. Want more robots? No problem, just make the sheet bigger. The sheet itself consists of six layers, which are all automatically laser machined: A pre-stretched polystyrene, or PSPS, layer (a kind of shape-memory polymer) in the center, sandwiched between layers of copper circuits etched into polyimide sheets, with paper substrates for support. The PSPS is the magical stuff: When heated above 100° C (which can be done by running a 2.5-ampere current through the copper circuitry), it shrinks, which is what powers the robots’ self-folding behaviors.

Otherwise, each robot consists of some discrete electrical components that have to be placed by hand, but according to co-author Michael Tolley, “we foresee straightforward ways to automate these steps.” Self-folding robots that use shape-memory polymers have been done before, but the challenge with them is to accurately control the folding. To address that issue, the Harvard researchers came up with a clever feedback-controlled assembly technique by using phototransistors and infrared LEDs to precisely measure the fold angles, “greatly improving the repeatability of self-folding,” says Tolley, who now leads UC San Diego’s Bioinspired Robotics and Design Lab.

The final thing that sets these self-folding bots apart is their ability to go from a single continuous sheet to a swarm of discrete robots. Self-folding joints that are designed to prevent folding causes the PSPS to instead rip itself apart, allowing each robot to split off by itself, where its vibration motors can help it buzz along flat surfaces seeking sources of light.

Columbia Engineering researchers have taken a key step toward atomically precise, reproducible transistors made from single molecules and operating at room temperature — a major goal in the field of molecular electronics.

The team created a two-terminal transistor with a diameter of about 0.5 nanometers and core consisting of just 14 atoms. The device can reliably switch from insulator to conductor when charge is added or removed, one electron at a time (known as “current blockade”).

The research was published in the journal Nature Nanotechnology. “With these molecular clusters, we have complete control over their structure with atomic precision and can change the elemental composition and structure in a controllable manner to elicit certain electrical response,” says Latha Venkataraman, leader of the Columbia research team.

The researchers plan to design improved molecular cluster systems with better electrical performance (such as higher on/off current ratio and different accessible states) and increase the number of atoms in the cluster core, while maintaining the atomic precision and uniformity of the compound.

Other studies have created quantum dots to produce similar effects, but the dots are much larger and not uniform in size, and the results have not been reproducible. The ultimate size reduction would be single-atom transistors, but they require ultra-cold temperatures (minus 196 degrees Celsius in this case, for example).

A group of scientists from Queen's University Belfast and the Max Planck Institute for solar system Research in Germany have turned exoplanet-hunting on its head, in a study that instead looks at how an alien observer might be able to detect Earth using our own methods. They find that at least nine exoplanets are ideally placed to observe transits of Earth, in a new work published in the journal Monthly Notices of the Royal Astronomical Society.

Thanks to facilities and missions such as SuperWASP and Kepler, we have now discovered thousands of planets orbiting stars other than our sun, worlds known as 'exoplanets'. The vast majority of these are found when the planets cross in front of their host stars in what are known as 'transits', which allow astronomers to see light from the host star dim slightly at regular intervals every time the planet passes between us and the distant star.

In the new study, the authors reverse this concept and ask, "How would an alien observer see the solar system?" They identified parts of the distant sky from where various planets in our solar system could be seen to pass in front of the sun – so-called 'transit zones'—concluding that the terrestrial planets (Mercury, Venus, Earth, and Mars) are actually much more likely to be spotted than the more distant 'Jovian' planets (Jupiter, Saturn, Uranus, and Neptune), despite their much larger size.

"Larger planets would naturally block out more light as they pass in front of their star", commented lead author Robert Wells, a PhD student at Queen's University Belfast. "However the more important factor is actually how close the planet is to its parent star – since the terrestrial planets are much closer to the sun than the gas giants, they'll be more likely to be seen in transit."

Physicists have developed a memory that can store photons. These quantum particles travel at the speed of light and are thus suitable for high-speed data transfer.

The researchers were able to store them in an atomic vapor and read them out again later without altering their quantum mechanical properties too much. This memory technology is simple and fast and it could find application in a future quantum Internet.The journal Physical Review Letters has published the results ("Simple Atomic Quantum Memory Suitable for Semiconductor Quantum Dot Single Photons").

A new technique that uses the artificial intelligence methods of machine learning and deep learning is able to create 3-D shapes from 2-D images, such as photographs, and is even able to create new, never-before-seen shapes.

Karthik Ramani, Purdue's Donald W. Feddersen Professor of Mechanical Engineering, says that the "magical" capability of AI deep learning is that it is able to learn abstractly. "If you show it hundreds of thousands of shapes of something such as a car, if you then show it a 2-D image of a car, it can reconstruct that model in 3-D," he says. "It can even take two 2-D images and create a 3-D shape between the two, which we call 'hallucination.'"

When fully developed, this method, called SurfNet, could have significant applications in the fields of 3-D searches on the Internet, as well as helping robotics and autonomous vehicles better understand their surroundings. Perhaps most exciting, however, is that the technique could be used to create 3-D content for virtual reality and augmented reality by simply using standard 2-D photos.

"You can imagine a movie camera that is taking pictures in 2-D, but in the virtual reality world everything is appearing magically in 3-D," Ramani says. "Inch-by-inch we are going there, and in the next five years something like this is going to happen.

TRAPPIST-1 is an ultracool dwarf star in the constellation Aquarius, 38.8 light-years away. It is barely larger than Jupiter and has just 8% of our Sun’s mass. It is rapidly spinning and generates energetic flares of ultraviolet (UV) radiation. This dwarf star is host to seven transiting planets, named TRAPPIST-1b, c, d, e, f, g and h. All these planets are similar in size to Earth and Venus, or slightly smaller, and have very short orbital periods.

They are likely all tidally locked, meaning the same face of the planet is always pointed at the star, as the same side of the Moon is always pointed at Earth. This creates a perpetual night side and perpetual day side on each TRAPPIST-1 planet.

TRAPPIST-1e, f and g lay in the star’s habitable zone, meaning they may harbor suitable conditions for life. Following up on the discovery, Dr. Vincent Bourrier of the Geneva Observatory and colleagues used Hubble’s Space Telescope Imaging Spectrograph to study the amount of UV radiation received by TRAPPIST-1 planets.

“UV radiation is an important factor in the atmospheric evolution of planets. As in Earth’s atmosphere, where UV sunlight breaks molecules apart, UV starlight can break water vapor in the atmospheres of exoplanets into hydrogen and oxygen,” Dr. Bourrier said. “While lower-energy UV radiation breaks up water molecules — a process called photodissociation — UV rays with more energy (XUV radiation) and X-rays heat the upper atmosphere of a planet, which allows the products of photodissociation, hydrogen and oxygen, to escape.”

“As it is very light, hydrogen gas can escape the exoplanets’ atmospheres and be detected around the exoplanets with Hubble, acting as a possible indicator of atmospheric water vapor,” Dr. Bourrier explains.

The observed amount of UV radiation emitted by the TRAPPIST-1 star indeed suggests that the planets could have lost gigantic amounts of water over the course of their history. This is especially true for the innermost two planets of the system, TRAPPIST-1b and TRAPPIST-1c, which receive the largest amount of UV energy. “Our results indicate that atmospheric escape may play an important role in the evolution of these planets,” said co-author Dr. Julien de Wit, of MIT.

It is one of the great mysteries in biology: How does a cell neatly distribute its replicated DNA between two daughter cells?

Condensin plays crucial roles in chromosome organization and compaction, but the mechanistic basis for its functions remained obscure, until now. A team of scientists recently used single-molecule imaging to demonstrate that eukaryotic condensin is a molecular motor capable of ATP hydrolysis-dependent translocation along double-stranded DNA. Condensin’s translocation activity is rapid and highly processive, with individual complexes traveling an average distance of ≥10 kilobases at a velocity of ~60 base pairs per second. These results suggest that condensin may take steps comparable in length to its ~50-nanometer coiled-coil subunits, suggestive of a translocation mechanism that is distinct from any reported DNA motor protein.

The finding that condensin is a mechanochemical motor has important implications for understanding the mechanisms of chromosome organization and condensation.

The role of condensin can sometimes be replaced by YY1.

A glacier crevasse has to be one of the worst places you could ever decide to fly a drone. It’s deep, dark, narrow, windy, and full of all kinds of nasty pointy bits, any one of which could collapse onto you at any time. This is also why you’d never want to enter one yourself, and why there aren’t any robots that are really able to go down into them to explore: it’s just horribly dangerous. From time to time, though, humans fall into crevasses, and then other humans have to (first) find them and then (hopefully) rescue them.

Switzerland-based startup Flyability partnered with the mountain rescue team at Zermatt Glacier in the Swiss Alps to offer them the services of Gimball, which is quite possibly the only robot that doesn’t care even a little bit whether you drop it into the bowels of a glacier. The drone took its HD camera and powerful lighting system deep into the ice, and came back out alive with video to prove it.

There are a bunch of other drones that come with protective cages of one sort or another, but Gimball is unique in that its protective cage is rotationally decoupled from the drone itself. This means that when the cage runs into something (like a massive ice wall), the force of the impact is absorbed by the cage and translated into rotational energy, while the drone inside remains stable and continues traveling generally in the direction that it was traveling in before. The upshot is that running into walls (or the floor or ceiling or whatever) is just not a big deal, and even untrained pilots can fly Gimball in treacherous places and still get back out in one piece.

Since DNA forms basepairs in a predictable way, by cleverly designing the sequences of several strands of DNA you can coax them to self-assemble into a particular shape.

Until recently, DNA origami has been constrained to two dimensional shapes like smiley faces, stars, and other things. These are entertaining, but this technology has potential applications besides aesthetic. Maybe one day we can build containers for drugs using DNA origami that carry medicine to particular cells, say chemotherapy drugs to cancer cells while sparing healthy cells from the same fate. Maybe one can take advantage of the stability of DNA by using it to build scaffolds on which tissues or whole organs can grow. These two applications clearly require taking DNA origami into three dimensions, which is just what Dongran Han and his colleagues did. In their designs they used one long piece of ssDNA, called the scaffold, and many small pieces of ssDNA, called staples. By choosing staples carefully, they were able to contort the scaffold into a desired shape. They began by building simple concentric circles in two dimensions with the scaffold weaving in and out between the rings. They then varied the parameters of their design to build three dimensional shapes with circular cross sections. They managed to build hemispheres, spheres, ellipsoids (stretched spheres), and flasks. They called their DNA flask the "nanoflask" in reference to its nanoscale size. The pictures of these shapes shown below are transmission electron micrographs in black and white and atomic force micrographs in yellow and red. Electron microscopes use a beam of electrons instead of light to focus on objects much smaller than the wavelength of visible light. Atomic force microscopes feel their way through a sample using a tiny needle tipped with a single atom.

Scientists discover the oldest homo sapiens fossils at Jebel Irhoud, Morocco

An international research team led by Jean-Jacques Hublin of the Max Planck Institute for Evolutionary Anthropology (Leipzig, Germany) and Abdelouahed Ben-Ncer of the National Institute for Archaeology and Heritage (INSAP, Rabat, Morocco) uncovered fossil bones of Homo sapiens along with stone tools and animal bones at Jebel Irhoud, Morocco. The finds are dated to about 300 thousand years ago and represent the oldest securely dated fossil evidence of our own species. This date is 100 thousand years earlier than the previous oldest Homo sapiens fossils. The discoveries reported in two papers in the June 8th issue of the journal Nature by Hublin et al. and by Richter et al. reveal a complex evolutionary history of mankind that likely involved the entire African continent.

Both genetic data of present day humans and fossil remains point to an African origin of our own species, Homo sapiens. Previously, the oldest securely datedHomo sapiens fossils were known from the site of Omo Kibish in Ethiopia, dated to 195 thousand years ago. At Herto, also in Ethiopia, a Homo sapiens fossil is dated to 160 thousand years ago. Until now, most researchers believed that all humans living today descended from a population that lived in East Africa around 200 thousand years ago. "We used to think that there was a cradle of mankind 200 thousand years ago in east Africa, but our new data reveal that Homo sapiensspread across the entire African continent around 300 thousand years ago. Long before the out-of-Africa dispersal of Homo sapiens, there was dispersal within Africa," says palaeoanthropologist Jean-Jacques Hublin.

A trio of researchers, two with the University of Idaho, the other with Wellesley College, has found evidence suggesting that two pairs of Uranus's moons are on a collision course.

Uranus is the seventh planet from the sun and the third largest. Prior research has suggested that it is, like Neptune, an ice giant (as compared to gas giants). It has also been found to have the chilliest atmosphere among all the planets in the solar system. And it has both a ring system and multiple satellites—27 in all. The satellites orbiting the planet are believed to be very low mass compared to the moons of the other planets, and some of them, according to this latest research, are on a collision course that will shatter them into small bits.

The researchers report that they were studying the planet's rings, which are collectively called Eta, and discovered that they had an oddly shaped orbit—not round or even circular. Instead, they describe it as sort of triangular. More study showed that the odd orbit of the rings was due to gravitational pull from Cressida—one of the planet's moons. The gravitational impact is exaggerated, they note, due to the moon keeping pace with the orbit of the planet. The particles in the ring, on the other hand, move faster than the moon. This results in the moon tugging on the ring at as it passes by, causing the odd orbital shape. The tug exerted by the moon on the rings allowed the team to deduce its mass. They found that it is around 1/300,000th that of our own moon. Also, it has only 86 percent of the density of water, which indicates it is porous.

In studying the orbits of the moons, the researchers found that Cressida is on a path that will cause it to collide with another moon called Desdemona, which currently moves in an orbit just 900 kilometers from Cressida's. The gravity of Cressida is slowly pulling them closer together and will cause them to crash into one another in approximately 1 million years. They also found the same to be true for Cupid and Belinda, which will collide sometime later.\

Men build dams and huge turbines to turn the energy of waterfalls and tides into electricity. To produce hydropower on a much smaller scale, Chinese scientists have now developed a lightweight power generator based on carbon nanotube fibers suitable to convert even the energy of flowing blood in blood vessels into electricity. They describe their innovation in the journal Angewandte Chemie ("A One-Dimensional Fluidic Nanogenerator with a High Power Conversion Efficiency").

For thousands of years, people have used the energy of flowing or falling water for their purposes, first to power mechanical engines such as watermills, then to generate electricity by exploiting height differences in the landscape or sea tides.Using naturally flowing water as a sustainable power source has the advantage that there are (almost) no dependencies on weather or daylight. Even flexible, minute power generators that make use of the flow of biological fluids are conceivable.How such a system could work is explained by a research team from Fudan University in Shanghai, China.

Huisheng Peng and his co-workers have developed a fiber with a thickness of less than a millimeter that generates electrical power when surrounded by flowing saline solution—in a thin tube or even in a blood vessel.The construction principle of the fiber is quite simple. An ordered array of carbon nanotubes was continuously wrapped around a polymeric core. Carbon nanotubes are well known to be electroactive and mechanically stable; they can be spun and aligned in sheets. In the as-prepared electroactive threads, the carbon nanotube sheets coated the fiber core with a thickness of less than half a micron. For power generation, the thread or "fiber-shaped fluidic nanogenerator" (FFNG), as the authors call it, was connected to electrodes and immersed into flowing water or simply repeatedly dipped into a saline solution.

"The electricity was derived from the relative movement between the FFNG and the solution," the scientists explained. According to the theory, an electrical double layer is created around the fiber, and then the flowing solution distorts the symmetrical charge distribution, generating an electricity gradient along the long axis.The power output efficiency of this system was high. Compared with other types of miniature energy-harvesting devices, the FFNG was reported to show a superior power conversion efficiency of more than 20%. Other advantages are elasticity, tunability, lightweight, and one-dimensionality, thus offering prospects of exciting technological applications. The FFNG can be made stretchable just by spinning the sheets around an elastic fiber substrate. If woven into fabrics, wearable electronics become thus a very interesting option for FFNG application.

Bosch has launched a system designed to monitor air quality in smart cities so officials can react quickly to improve the quality of life. The system, the Bosch Air Quality Micro Climate Monitoring System (MCMS), is based on Intel technology, sensors and software to measure air quality.

MCMS offers microclimate data measurements for EPA pollutants, including particulate matter, carbon monoxide, carbon dioxide, nitric oxide, nitrogen dioxide, sulfur dioxide and ozone. MCMS also tracks temperature, humidity, light, sound and pressure. With the data compiled, MCMS can analyze conditions and then adjust traffic flow and change emissions at factories and industrial settings. Construction sites can also provide early warning signals based on conditions.

MCMS, available now, is compact and built for rugged conditions. It includes remote monitoring via wired and wireless interfaces. Sensors can also be calibrated over the air. In addition, MCMS is based on Intel's IoT reference architecture, Wind River Helix Device Cloud, for edge devices and security tools.

Want to make phosphorescent ink? Dope it with some europium.

A team of scientists have demonstrated for the first time an inkjet fabrication of highly efficient luminescent structures based on Eu-doped ZrO2 nanocrystals (3.4 ± 0.3 nm), with a refractive index close to the one of the bulk materials. The nanoparticles were synthesized using a non-hydrolytic method in benzyl alcohol where the particles were post treated using acetic acid, leading to the formation of a stable colloid. It was shown that the non-polar methyl group of the acetic acid is responsible for its penetration through the hydrophobic layer all the way through to the surface of the ZrO2, leading to the cleavage of the Zr–OCH2C6H5 bond and the formation of surface acetate species and a concomitant decomposition of the zirconia superlattice.

They show us a new and efficient universal ink production through a multi-step process – starting from solvothermal synthesis, dispersion of nanocrystals in water, and adaptation of the rheological parameters of the resulting sols. Eventually, they were able to obtain inks that could be used for the production of optical coatings, monolayer luminescent-protected holography and anti-counterfeiting printing. These structures, obtained at room temperature through inkjet printing, present dense xerogel structures with high optical transparency, a high refractive index and more efficient luminescence compared with the non-homogeneous structures produced as a mixture of rare-earth elements and nanocrystals.

Florence, an asteroid that came within 4.4 million miles (7.0 million kilometers) of Earth last week, has two small moons, according to radar images obtained by NASA.

Radar images obtained between August 29 and September 1, when Florence came closest to Earth, reveal that the asteroid is about 2.8 miles (4.5 kilometers) in size, the US space agency said.

It said the two moons were probably between 300-1,000 feet (100-300 meters) across. The inner moon takes approximately eight hours to revolve around Florence while the outer moon takes between 22 and 27 hours, NASA said.

According to NASA, 60 near-Earth asteroids are known to have moons and Florence is the first observed with two moons since Asteroid 1994 in June 2009. NASA said the radar images of Florence, which was discovered in 1981, were obtained by the Goldstone Deep Space Communications Complex in California.

"While many known asteroids have passed by closer to Earth than Florence... all of those were estimated to be smaller," said Paul Chodas, manager of NASA's Center for Near-Earth Object Studies (CNEOS) at the Jet Propulsion Laboratory in Pasadena, California. "Florence is the largest asteroid to pass by our planet this close since the NASA program to detect and track near-Earth asteroids began."

Engineers at Australia's University of New South Wales have invented a radical new architecture for quantum computing, based on novel 'flip-flop qubits', that promises to make the large-scale manufacture of quantum chips dramatically cheaper - and easier - than thought possible.

The new chip design, detailed in the journal Nature Communications, allows for a silicon quantum processor that can be scaled up without the precise placement of atoms required in other approaches. Importantly, it allows quantum bits (or 'qubits') - the basic unit of information in a quantum computer - to be placed hundreds of nanometres apart and still remain coupled.

The design was conceived by a team led by Andrea Morello, Program Manager in UNSW-based ARC Centre of Excellence for Quantum Computation and Communication Technology (CQC2T) in Sydney, who said fabrication of the new design should be easily within reach of today's technology.

Lead author Guilherme Tosi, a Research Fellow at CQC2T, developed the pioneering concept along with Morello and co-authors Fahd Mohiyaddin, Vivien Schmitt and Stefanie Tenberg of CQC2T, with collaborators Rajib Rahman and Gerhard Klimeck of Purdue University in the USA. "It's a brilliant design, and like many such conceptual leaps, it's amazing no-one had thought of it before," said Morello.