A Soft Robotic Insect That Survives The Fly Swatter

December 31, 2019 by Sharon Lin 7 Comments

Swarms of robotic insects incapable of being swatted away may no longer be the product of science fiction and Black Mirror episodes. A team from EPFL’s School of Engineering has developed an insect propelled at 3 cm/s, dubbed the DEAnsect.

What makes this robot unique is its exceptional robustness. Two versions of the robot were initially developed, one tethered with ultra-thin wires capable of being squashed with a shoe without impacting its functions and the second fully wireless and autonomous. The robot weighs less than 1 gram and is equipped with a microcontroller and photodiodes to recognize black and white patterns.

The insect is named for its dielectric elastomer actuators (DEAs), an artificial muscle that propels it with vibrations and enables it to move lightly and quickly.

The DEAs are made of an elastomer membrane wedged between soft electrodes that are attracted to each other when a voltage is applied, compressing the membrane. The membrane returns to its original shape when the voltage is turned off. Movement is generated by switching the voltage on and off over 400 times per second. The team reduced the thickness of the membranes and developed soft, highly conductive electrodes only several molecules thick using nanofabrication techniques. They plan on fitting even more sensors and emitters to allow the insects to communicate directly with one another for greater swarm-like activity.

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Magic-Angle Twisted Bilayer Graphene – Yes, That’s The Scientific Name

December 27, 2019 by Sharon Lin 14 Comments

In the world of physics research, graphene has been gaining popularity as one of the most remarkable materials in the last 15 years. While it may appear unassuming in common household goods such as pencil leads, the material boasts a higher strength than steel and a higher flexibility than paper. On top of all that, it is also ultra-light and an excellent conductor of electric current and heat.

Recently, physicists from the Massachusetts Institute of Technology discovered that stacking two sheets of graphene and twisting a small angle between them reveals an entire new field of material science – twistronics. In a paper published in Nature, researchers have taken a look into this new material, known as the magic-angle twisted bilayer graphene. By modifying the graphene’s temperature, they were able to cause the material to shift from behaving like an insulator to transforming into a superconductor.

A graphic in the New York Times demonstrates some of the interesting properties that arise from stacking and twisting two sheets. Scientists have long known that graphene is a one-layer-thick honeycombed pattern of carbon atoms, but actually separating a single sheet of graphene has been fairly difficult. A low-tech method pioneered by two physicists at the University of Manchester involves using sticky tape to pull apart graphene layers until a single layer is left.

Small imperfections that arise from slightly misaligned sheets manifests in a pattern that allows electrons to hop between atoms in regions where the lattice line up, but unable to flow in regions that are misaligned. The slower moving electrons are thus more likely to interact with each other, becoming “strongly correlated”.

The technique for measuring the properties of this new twisted graphene is similarly low-tech. After a single layer of graphene is separated by sticky tape, the tape is torn in half to reveal two halves with perfectly aligned lattices. One of the sides is rotated by about 1.3 degrees and pressed onto the other. Sometimes, the layers would snap back into alignment, but other times they would end up at 1.1 degrees and stop rotating.

When the layers were cooled to a fraction of a degree above absolute zero, they were observed to become a superconductor, an incredibly discovery for the physicists involved in the experiment. Further studies showed that different permutations of temperature, magnetic field, and electron density were also able to turn the graphene into a superconductor. On top of this, the graphene was also able to exhibit a form of magnetism arising from the movement of electrons rather than the intrinsic properties of the atoms. With so many possibilities still unexplored, it’s certain that twistronics will reveal some remarkable findings pretty soon.

[Thanks Adrian for the tip!]

The Birth Of The Modern Robot

December 19, 2019 by Sharon Lin 26 Comments

When Isaac Asmiov was writing I, Robot, the field of robotics was still in its infancy. As he notes in The Complete Robot, as the field began to mature, it started showing signs of conforming to the popular ideas held by science fiction writers about what robotics ought to be. Notions of humanoid robots, the functions that robots would have in domestic settings, even the ethical quandaries that AI ethicists face today were all themes of early sci-fi writers.

The idea of a robot – at least of automata – predates the field of robotics. The idea of an independent automata may have existed as early as the ancient Egyptians Chinese, and Greeks, who attempted to build self-operated machines that resembled animals and humans. Myths of clay golems in Jewish legends and clay giants in Norse legends perpetuated the idea of an artificial being that could mimic the actions of living creatures. A 400 BC myth from Crete spoke of a man of bronze who guarded their island from pirates.

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Interview: FieldKit Team The Morning After Winning The 2019 Hackaday Prize

December 13, 2019 by Mike Szczys 1 Comment

We caught up with Shah Selbe and Jacob Lewallen the morning after their project, FieldKit, won the Hackaday Prize. FieldKit is an open-source field-based research data collection platform. Which is basically a lot of fancy words for saying it’s a system for collecting sensor data in the field without being snagged by the myriad of problems associated with putting electronics in remote locations. It’s a core project of Conservify, a non-profit organization that seeks to empower conservation research.

As grand prize winner the FieldKit project was awarded a $125,000 cash prize, which Shah and Jacob say is transformative for a non-profit pursuing technology research and development. It seems the grant process has not evolved to embrace developing electronics, while opportunities for research projects have begun to involve recording large data sets in order to test a hypothesis. This is where FieldKit truly shines. Their vision is to provide a low-cost and extensible system that other researchers can use to collect data while making their own grant dollar go much further.

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Robot Vs. Superbug

November 30, 2019 by Bryan Cockfield 6 Comments

Working in a university or research laboratory on interesting, complicated problems in the sciences has a romanticized, glorified position in our culture. While the end results are certainly worth celebrating, often the process of new scientific discovery is underwhelming, if not outright tedious. That’s especially true in biology and chemistry, where scaling up sample sizes isn’t easy without a lot of human labor. A research group from Reading University was able to modify a 3D printer to take some of that labor out of the equation, though.

This 3D printer was used essentially as a base, with the printing head removed and replaced with a Raspberry Pi camera. The printer X/Y axes move the camera around to all of the different sample stored in the print bed, which allows the computer attached to the printer to do most of the work that a normal human would have had to do. This allows them to scale up massively and cheaply, presumably with less tedious inputs from a large number of graduate students.

While the group hopes that this method will have wide applicability for any research group handling large samples, their specific area of interest involves researching “superbugs” or microbes which have developed antibiotic resistance. Their recently-published paper states that any field which involves bacterial motility, colony growth, microtitre plates or microfluidic devices could benefit from this 3D printer modification.

Your WiFi Signals Are Revealing Your Location

November 28, 2019 by Sharon Lin 43 Comments

The home may be the hearth, but it’s not going to be a place of safety for too long.

With the abundance of connected devices making their ways into our homes, increasing levels of data may allow for more accurate methods for remote surveillance. By measuring the strength of ambient signals emitted from devices, a site can be remotely monitored for movement. That is to say, WiFi signals may soon pose a physical security vulnerability.

In a study from the University of Chicago and the University of California, Santa Barbara, researchers built on earlier studies where they could use similar techniques to “see through walls” to demonstrate a proof-of-concept for passive listening. Attackers don’t need to transmit signals or break encryptions to gain access to a victim’s location – they just need to listen to the ambient signals coming from connected devices, making it more difficult to track bad actors down.

Typically, connected devices communicate to an access point such as a router rather than directly with the Internet. A person walking near a device can subtly change the signal propagated to the access point, which is picked up by a receiver sniffing the signal. Most building materials do not block WiFi signals from propagating, allowing receivers to be placed inconspicuously in different rooms from the access point.

WiFi sniffers are relatively inexpensive, with models running for less than $20. They’re also small enough to hide in unsuspecting locations – inside backpacks, inside a box – and emit no signal that could be detected by a target. The researchers proposed some methods for safeguarding against the vulnerability: insulating buildings against WiFi leakage (while ensuring that desirable signals, i.e. signals from cell tower are still able to enter) or having access points emit a “cover signal” that mixes signals from connected devices to make it harder to sniff for motion.

While we may not be seeing buildings surrounded by Faraday cages anytime soon, there’s only going to be more attack surfaces to worry about as our devices continue to become connected.

[Thanks to Qes for the tip!]

A Single-Digit-Micrometer Thickness Wood Speaker

November 27, 2019 by Sharon Lin 22 Comments

Researchers have created an audio speaker using ultra-thin wood film. The new material demonstrates high tensile strength and increased Young’s modulus, as well as acoustic properties contributing to higher resonance frequency and greater displacement amplitude compared to a commercial polypropylene diaphragm in an audio speaker.

Typically, acoustic membranes have to remain very thin (on the micron scale) and robust in order to allow for a highly sensitive frequency response and vibrational amplitude. Materials made from plastic, metal, ceramic, and carbon have been used by engineers and physicists in an attempt to enhance the quality of sound. While plastic thin films are most commonly manufactured, they have a pretty bad impact on the environment. Meanwhile, metal, ceramic, and carbon-based materials are more expensive and less attractive to manufacturers as a result.

Cellulose-based materials have been making an entrance in acoustics research with their environmentally friendly nature and natural wooden structure. Materials like bagasse, wood fibers, chitin, cotton, bacterial cellulose, and lignocellulose are all contenders for effective alternatives to parts currently produced from plastics.

The process for building the ultra-thin film involved removing lignin and hemicellulose from balsa wood, resulting in a highly porous material. The result is hot pressed for a thickness reduction of 97%. The cellulose nano-fibers remain oriented but more densely packed compared to natural wood. In addition, the fibers required higher energy to be pulled apart while remaining flexible and foldable.

At one point in time, plastics seemed to be the hottest new material, but perhaps wood is making a comeback?

[Thanks Qes for the tip!]