Checking blood pressure in a heartbeat, using artificial intelligence and a camera

The new technology demonstrates how a camera and artificial intelligence can be used to extract cardiac signals from a person's forehead.
Photo Credit:  University of South Australia

Monitoring blood pressure using a digital camera could soon be the norm, thanks to an innovative technique demonstrated by Australian and Iraqi researchers.

Using the same remote-health technology they pioneered to monitor vital health signs from a distance, engineers from the University of South Australia and Baghdad’s Middle Technical University have designed a non-contact system to accurately measure systolic and diastolic pressure.

The researchers claim that it could replace the existing uncomfortable and cumbersome method of strapping an inflatable cuff to a patient’s arm or wrist, the researchers claim.

In a new paper published in Inventions, the researchers describe the technique, which involves filming a person from a short distance for 10 seconds and extracting cardiac signals from two regions in the forehead, using artificial intelligence algorithms.

The systolic and diastolic readings were around 90 per cent accurate, compared to the existing instrument (a digital sphygmomanometer) used to measure blood pressure, that is itself subject to errors.

New Stanford chip-scale laser isolator could transform photonics

From left, Alexander White, Geun Ho Ahn, and Jelena Vučković with the nanoscale isolator.
Photo Credit: Hannah Kleidermacher

Using well-known materials and manufacturing processes, researchers have built an effective, passive, ultrathin laser isolator that opens new research avenues in photonics.

Lasers are transformational devices, but one technical challenge prevents them from being even more so. The light they emit can reflect back into the laser itself and destabilize or even disable it. At real-world scales, this challenge is solved by bulky devices that use magnetism to block harmful reflections. At chip scale, however, where engineers hope lasers will one day transform computer circuitry, effective isolators have proved elusive.

Against that backdrop, researchers at Stanford University say they have created a simple and effective chip-scale isolator that can be laid down in a layer of semiconductor-based material hundreds of times thinner than a sheet of paper.

“Chip-scale isolation is one of the great open challenges in photonics,” said Jelena Vučković, a professor of electrical engineering at Stanford and senior author of the study appearing Dec. 1 in the journal Nature Photonics.

“Every laser needs an isolator to stop back reflections from coming into and destabilizing the laser,” said Alexander White, a doctoral candidate in Vučković’s lab and co-first author of the paper, adding that the device has implications for everyday computing, but could also influence next-generation technologies, like quantum computing.

To Battle Climate Change, Scientists Tap into Carbon-Hungry Microorganisms for Clues

Electron microscopy images of 7-nanometer-diameter copper nanoparticles (shown left) and silver nanoparticles (center). At right: Electron microscopy image of ultrathin material synthesized from copper and silver nanoparticles, which could potentially be coupled with light-absorbing silicon nanowires for the design of efficient artificial photosynthesis systems. 
Credit: Peidong Yang/Berkeley Lab; courtesy of Nature Catalysis

Scientists at Lawrence Berkeley National Laboratory (Berkeley Lab) have demonstrated a new technique, modeled after a metabolic process found in some bacteria, for converting carbon dioxide (CO2) into liquid acetate, a key ingredient in “liquid sunlight” or solar fuels produced through artificial photosynthesis.

The new approach, reported in Nature Catalysis, could help advance carbon-free alternatives to fossil fuels linked to global warming and climate change.

The work is also the first demonstration of a device that mimics how these bacteria naturally synthesize acetate from electrons and CO2.

“What’s amazing is that we learned how to selectively convert carbon dioxide into acetate by mimicking how these little microorganisms do it naturally,” said senior author Peidong Yang, who holds titles of senior faculty scientist in Berkeley Lab’s Materials Sciences Division and professor of chemistry and materials science and engineering at UC Berkeley.

Breaking the scaling limits of analog computing

MIT researchers have developed a technique that greatly reduces the error in an optical neural network, which uses light to process data instead of electrical signals. With their technique, the larger an optical neural network becomes, the lower the error in its computations. This could enable them to scale these devices up so they would be large enough for commercial uses.
Credit: SFLORG stock photo

As machine-learning models become larger and more complex, they require faster and more energy-efficient hardware to perform computations. Conventional digital computers are struggling to keep up.

An analog optical neural network could perform the same tasks as a digital one, such as image classification or speech recognition, but because computations are performed using light instead of electrical signals, optical neural networks can run many times faster while consuming less energy.

However, these analog devices are prone to hardware errors that can make computations less precise. Microscopic imperfections in hardware components are one cause of these errors. In an optical neural network that has many connected components, errors can quickly accumulate.

Even with error-correction techniques, due to fundamental properties of the devices that make up an optical neural network, some amount of error is unavoidable. A network that is large enough to be implemented in the real world would be far too imprecise to be effective.

MIT researchers have overcome this hurdle and found a way to effectively scale an optical neural network. By adding a tiny hardware component to the optical switches that form the network’s architecture, they can reduce even the uncorrectable errors that would otherwise accumulate in the device.

New device can control light at unprecedented speeds

Scientists have developed a programmable, wireless spatial light modulator that can manipulate light at the wavelength scale with orders-of-magnitude faster response than existing devices.
Illustration Credit: Sampson Wilcox

In a scene from “Star Wars: Episode IV — A New Hope,” R2D2 projects a three-dimensional hologram of Princess Leia making a desperate plea for help. That scene, filmed more than 45 years ago, involved a bit of movie magic — even today, we don’t have the technology to create such realistic and dynamic holograms.

Generating a freestanding 3D hologram would require extremely precise and fast control of light beyond the capabilities of existing technologies, which are based on liquid crystals or micromirrors.

An international group of researchers, led by a team at MIT, spent more than four years tackling this problem of high-speed optical beam forming. They have now demonstrated a programmable, wireless device that can control light, such as by focusing a beam in a specific direction or manipulating the light’s intensity, and do it orders of magnitude more quickly than commercial devices.

They also pioneered a fabrication process that ensures the device quality remains near-perfect when it is manufactured at scale. This would make their device more feasible to implement in real-world settings.

NIST Finds a Sweet New Way to Print Microchip Patterns on Curvy Surfaces

Using sugar and corn syrup (i.e., candy), researcher Gary Zabow transferred the word "NIST" onto a human hair in gold letters, shown in false color in this grayscale microscope image. 
Image Credit: G. Zabow/NIST

NIST scientist Gary Zabow had never intended to use candy in his lab. It was only as a last resort that he had even tried burying microscopic magnetic dots in hardened chunks of sugar — hard candy, basically — and sending these sweet packages to colleagues in a biomedical lab. The sugar dissolves easily in water, freeing the magnetic dots for their studies without leaving any harmful plastics or chemicals behind.

By chance, Zabow had left one of these sugar pieces, embedded with arrays of micromagnetic dots, in a beaker, and it did what sugar does with time and heat — it melted, coating the bottom of the beaker in a gooey mess.

“No problem,” he thought. He would just dissolve away the sugar, as normal. Except this time when he rinsed out the beaker, the microdots were gone. But they weren’t really missing; instead of releasing into the water, they had been transferred onto the bottom of the glass where they were casting a rainbow reflection.

“It was those rainbow colors that really surprised me,” Zabow recalls. The colors indicated that the arrays of microdots had retained their unique pattern.

The whole in a part: Synchronizing chaos through a narrow slice of spectrum

Conceptual overview of the coupling scheme between a master and a slave chaotic oscillator via a band-pass filter, and the resulting complex interdependence between their activities.
Credit: Tokyo Institute of Technology

Engineers at the Tokyo Institute of Technology (Tokyo Tech) have uncovered some intricate effects arising when chaotic systems, which typically generate broad spectra, are coupled by conveying only a narrow range of frequencies from one to another. The synchronization of chaotic oscillators, such as electronic circuits, continues to attract considerable fascination due to the richness of the complex behaviors that can emerge. Recently, hypothetical applications in distributed sensing have been envisaged, however, wireless couplings are only practical over narrow frequency intervals. The proposed research shows that, even under such constraints, chaos synchronization can occur and give rise to phenomena that could one day be leveraged to realize useful operations over ensembles of distant nodes.

The abstract notion that the whole can be found in each part of something has for long fascinated thinkers engaged in all walks of philosophy and experimental science: from Immanuel Kant on the essence of time to David Bohm on the notion of order, and from the self-similarity of fractal structures to the defining properties of holograms. It has, however, remained understandably extraneous to electronic engineering, which strives to develop ever more specialized and efficient circuits exchanging signals that possess highly controlled characteristics. By contrast, across the most diverse complex systems in nature, such as the brain, the generation of activity having features that present themselves similarly over different temporal scales, or frequencies, is nearly a ubiquitous observation.

Researchers use blockchain to increase electric grid resiliency

A team led by Raymond Borges Hink has developed a method using blockchain to protect communications between electronic devices in the electric grid, preventing cyberattacks and cascading blackouts.
Photo Credit: Genevieve Martin/ORNL, U.S. Dept. of Energy

Although blockchain is best known for securing digital currency payments, researchers at the Department of Energy’s Oak Ridge National Laboratory are using it to track a different kind of exchange: It’s the first time blockchain has ever been used to validate communication among devices on the electric grid.

The project is part of the ORNL-led Darknet initiative, funded by the DOE Office of Electricity, to secure the nation’s electricity infrastructure by shifting its communications to increasingly secure methods.

Cyber risks have increased with two-way communication between grid power electronics equipment and new edge devices ranging from solar panels to electric car chargers and intelligent home electronics. By providing a trust framework for communication among electrical devices, an ORNL research team led by Raymond Borges Hink is increasing the resilience of the electric grid. The team developed a framework to detect unusual activity, including data manipulation, spoofing and illicit changes to device settings. These activities could trigger cascading power outages as breakers are tripped by protection devices.

Flocks of assembler robots show potential for making larger structures

Researchers at MIT have made significant steps toward creating robots that could practically and economically assemble nearly anything, including things much larger than themselves, from vehicles to buildings to larger robots. The new system involves large, usable structures built from an array of tiny identical subunits called voxels (the volumetric equivalent of a 2-D pixel).
Photo Credit: Massachusetts Institute of Technology | Courtesy of the researchers

Researchers at MIT have made significant steps toward creating robots that could practically and economically assemble nearly anything, including things much larger than themselves, from vehicles to buildings to larger robots.

The new work, from MIT’s Center for Bits and Atoms (CBA), builds on years of research, including recent studies demonstrating that objects such as a deformable airplane wing and a functional racing car could be assembled from tiny identical lightweight pieces — and that robotic devices could be built to carry out some of this assembly work. Now, the team has shown that both the assembler bots and the components of the structure being built can all be made of the same subunits, and the robots can move independently in large numbers to accomplish large-scale assemblies quickly.

The new work is reported in the journal Nature Communications Engineering, in a paper by CBA doctoral student Amira Abdel-Rahman, Professor and CBA Director Neil Gershenfeld, and three others.

A fully autonomous self-replicating robot assembly system capable of both assembling larger structures, including larger robots, and planning the best construction sequence is still years away, Gershenfeld says. But the new work makes important strides toward that goal, including working out the complex tasks of when to build more robots and how big to make them, as well as how to organize swarms of bots of different sizes to build a structure efficiently without crashing into each other.

Lab discovery leads UAH researchers to a simple, cost-effective electricity generator

Dr. Moonhyung Jang, left, operates the generator to light an LED display as Dr. Gang Wang looks on in the Adaptive Structures Laboratory. 
Photo Credit: Michael Mercier | University of Alabama in Huntsville

A bit of laboratory serendipity led University of Alabama in Huntsville (UAH) researchers to a simple mechanical way to generate electricity to operate electronic devices, says a paper they have published in the journal ACS Omega.

Triboelectric nanogenerators use multiple layers of different materials to generate electricity when pressed. While testing a triboelectric nanogenerator in the Adaptive Structures Laboratory of Dr. Gang Wang at UAH, a part of the University of Alabama System, postdoctoral research assistant Dr. Moonhyung Jang observed something unusual.

“During a finger-tapping test performed by Dr. Jang, a Scotch tape was introduced on the top to prevent electric shock,” says Dr. Wang, an associate professor of mechanical and aerospace engineering and the project’s principal investigator.

“An unexpectedly high voltage was observed. After a careful investigation, we figured out that the tape layer is the reason to cause this,” Dr. Wang says. “This led to our invention that introduces tacky materials to improve the performance of triboelectric generators.”

Technique Prints Flexible Circuits on Curved Surfaces, From Contact Lenses to Latex Gloves

Photo Credit: Yuxuan Liu.

Researchers from North Carolina State University have demonstrated a new technique for directly printing electronic circuits onto curved and corrugated surfaces. The work paves the way for a variety of new soft electronic technologies, and researchers have used the technique to create prototype “smart” contact lenses, pressure-sensitive latex gloves, and transparent electrodes.

“There are many existing techniques for creating printed electronics using various materials, but limitations exist,” says Yong Zhu, corresponding author of a paper on the work. “One challenge is that existing techniques require the use of polymer binding agents in the ‘ink’ you use to print the circuits. This impairs the circuit’s conductivity, so you have to incorporate an additional step to remove those binding agents after printing.

“A second challenge is that these printing techniques typically require you to print on flat surfaces, but many applications require surfaces that aren’t flat,” says Zhu, who is the Andrew A. Adams Distinguished Professor of Mechanical and Aerospace Engineering at NC State.

“We’ve developed a technique that doesn’t require binding agents and that allows us to print on a variety of curvilinear surfaces,” says Yuxuan Liu, first author of the paper and a Ph.D. student at NC State. ‘It also allows us to print the circuits as grid structures with uniform thickness.”

New chainsaw drone technology deployed to fight Rapid ʻŌhiʻa Death

A new aerial chainsaw device that could assist in the battle to save Hawaiʻi’s ʻōhiʻa trees from a deadly fungal pathogen is being put to the test by a University of Hawaiʻi at Hilo geographer. Professor Ryan Perroy and his research team have developed a drone attachment capable of sampling tree branch samples for diagnostic laboratory testing and other purposes.

The device consists of a small rotating chainsaw with a robotic gripper claw mounted beneath the drone

The device, named Kūkūau, consists of a small rotating chainsaw with a robotic gripper claw mounted beneath a drone, and can cut and retrieve branches up to seven centimeters in diameter. The samples are collected for diagnostic testing of forest fungal pathogens, including those responsible for Rapid ʻŌhiʻa Death (ROD).

“There have been times when we detected an ʻōhiʻa tree suspected of infection with the pathogens responsible for Rapid ʻŌhiʻa Death, but because of the location, it was too dangerous or problematic to send field crews out to sample it for confirmation,” said Perroy. “Kūkūau has the potential to help in those types of situations.”

Electronic/Photonic Chip Sandwich Pushes Boundaries of Computing and Data Transmission Efficiency

Image: The chip sandwich: an electronics chip (the smaller chip on the top) integrated with a photonics chip, sitting atop a penny for scale.
Photo Credit: Arian Hashemi Talkhooncheh

Engineers at Caltech and the University of Southampton in England have collaboratively designed an electronics chip integrated with a photonics chip (which uses light to transfer data)—creating a cohesive final product capable of transmitting information at ultrahigh speed while generating minimal heat.

Though the two-chip sandwich is unlikely to find its way into your laptop, the new design could influence the future of data centers that manage very high volumes of data communication.

"Every time you are on a video call, stream a movie, or play an online video game, you're routing data back and forth through a data center to be processed," says Caltech graduate student Arian Hashemi Talkhooncheh (MS '16), lead author of a paper describing the two-chip innovation that was published in the IEEE Journal of Solid-State Circuits. "There are more than 2,700 data centers in the U.S. and more than 8,000 worldwide, with towers of servers stacked on top of each other to manage the load of thousands of terabytes of data going in and out every second."

Just as your laptop heats up on your lap while you use it, the towers of servers in data centers that keep us all connected also heat up as they work, just at a much greater scale. Some data centers are even built underwater to cool the whole facility more easily. The more efficient they can be made, the less heat they will generate, and ultimately, the greater the volume of information that they will be able to manage.

Fruit flies use corrective movements to maintain stability after injury

Collaborators at the University of Colorado Boulder created a robotic wing made of plastic and cardboard laminate to study the mechanism by which fruit flies compensate for wing damage in flight. Photo Credit: Kaushik Jayaram

Fruit flies can quickly compensate for catastrophic wing injuries, researchers found, maintaining the same stability after losing up to 40% of a wing. This finding could inform the design of versatile robots, which face the similar challenge of having to quickly adapt to mishaps in the field.

The Penn State-led team published their results in Science Advances.

To run the experiment, researchers altered the wing length of anesthetized fruit flies, imitating an injury flying insects can sustain. They then suspended the flies in a virtual reality ring. Mimicking what flies would see when in flight, researchers played virtual imagery on tiny screens in the ring, causing the flies to move as if flying.

“We found flies compensate for their injuries by flapping the damaged wing harder and reducing the speed of the healthy one,” said corresponding author Jean-Michel Mongeau, Penn State assistant professor of mechanical engineering. “They accomplish this by modulating signals in their nervous system, allowing them to fine-tune their flight even after an injury.”

‘Butterfly Bot’ is Fastest Swimming Soft Robot Yet

Inspired by the biomechanics of the manta ray, researchers at North Carolina State University have developed an energy-efficient soft robot that can swim more than four times faster than previous swimming soft robots. The robots are called “butterfly bots,” because their swimming motion resembles the way a person’s arms move when they are swimming the butterfly stroke.

“To date, swimming soft robots have not been able to swim faster than one body length per second, but marine animals – such as manta rays – are able to swim much faster, and much more efficiently,” says Jie Yin, corresponding author of a paper on the work and an associate professor of mechanical and aerospace engineering at NC State. “We wanted to draw on the biomechanics of these animals to see if we could develop faster, more energy-efficient soft robots. The prototypes we’ve developed work exceptionally well.”

The researchers developed two types of butterfly bots. One was built specifically for speed, and was able to reach average speeds of 3.74 body lengths per second. A second was designed to be highly maneuverable, capable of making sharp turns to the right or left. This maneuverable prototype was able to reach speeds of 1.7 body lengths per second.

Cyber vulnerability in networks used by spacecraft, aircraft and energy generation systems

A new attack discovered by the University of Michigan and NASA exploits a trusted network technology to create unexpected and potentially catastrophic behavior

A major vulnerability in networking technology widely used in critical infrastructures such as spacecraft, aircraft, energy generation systems and industrial control systems was exposed by researchers at the University of Michigan and NASA.

It goes after a network protocol and hardware system called time-triggered ethernet, or TTE, which greatly reduces costs in high-risk settings by allowing mission-critical devices (like flight controls and life support systems) and less important devices (like passenger WiFi or data collection) to coexist on the same network hardware. This blend of devices on a single network arose as part of a push by many industries to reduce network costs and boost efficiency.

That coexistence has been considered safe for more than a decade, predicated on a design that prevented the two types of network traffic from interfering with one another. The team’s attack, called PCspooF, was the first of its kind to break this isolation.

In one compelling demonstration, the team used real NASA hardware to recreate a planned Asteroid Redirection Test. The experimental setup controlled a simulated crewed capsule, specifically at the point in the mission when the capsule prepared to dock with a robotic spacecraft.

Boeing Demonstrates New Autonomous Anti-Jam Capabilities for U.S. Space Force Satellite Communications Program

Boeing engineers recently demonstrated its space-based smart antenna technology, which detects enemy jammers and autonomously reshapes a satellite’s beams to suppress hostile jammers while maintaining communications with the friendly-force PTS terminals. Boeing’s system brings communication to the warfighter at closer range to the enemy.
Photo Credit: Boeing

Boeing engineers recently demonstrated a new, autonomous technology that can successfully prevent jamming attempts on U.S. Department of Defense satellite communications (SATCOM). The test was conducted on the U.S. Space Force’s Protected Tactical SATCOM Prototype (PTS-P), showing how this technology can provide secure communication in contested environments.

“Maintaining communication with our deployed forces during hostility gives us a tactical edge on the battlefield,” said Justin Bruner, PTS-P Program Manager at the U.S. Space Force. “Our adversaries are always attempting to deny our ability to communicate. On-board, autonomous, real-time nulling of jammers greatly enhances our resiliency, ensuring the United States and our allies can provide our warfighters with secure, reliable communications in a contested environment. Boeing has made significant strides in the development and execution of a nulling algorithm with flight-like firmware, demonstrating agile anti-jam capability. PTS-P and all of our Protected Anti-Jam Tactical SATCOM (PATS) programs are critical to this effort.”

New discoveries made about a promising solar cell material, thanks to new microscope

Visualization of the microscope tip exposing material to terahertz light. The colors on the material represent the light-scattering data, and the red and blue lines represent the terahertz waves.
Illustration Credit: Ames National Laboratory

A team of scientists from the Department of Energy’s Ames National Laboratory developed a new characterization tool that allowed them to gain unique insight into a possible alternative material for solar cells. Under the leadership of Jigang Wang, senior scientist from Ames Lab, the team developed a microscope that uses terahertz waves to collect data on material samples. The team then used their microscope to explore Methylammonium Lead Iodide (MAPbI3) perovskite, a material that could potentially replace silicon in solar cells.

Richard Kim, a scientist from Ames Lab, explained the two features that make the new scanning probe microscope unique. First, the microscope uses the terahertz range of electromagnetic frequencies to collect data on materials. This range is far below the visible light spectrum, falling between the infrared and microwave frequencies. Secondly, the terahertz light is shined through a sharp metallic tip that enhances the microscope’s capabilities toward nanometer length scales.

“Normally if you have a light wave, you cannot see things smaller than the wavelength of the light you're using. And for this terahertz light, the wavelength is about a millimeter, so it’s quite large,” explained Kim. “But here we used this sharp metallic tip with an apex that is sharpened to a 20-nanometer radius curvature, and this acts as our antenna to see things smaller than the wavelength that we were using.”

Autonomous Crawling Soft ‘Ringbots’ Can Navigate Narrow Gaps

Researchers at North Carolina State University have created a ring-shaped soft robot capable of crawling across surfaces when exposed to elevated temperatures or infrared light. The researchers have demonstrated that these “ringbots” are capable of pulling a small payload across the surface – in ambient air or under water, as well as passing through a gap that is narrower than its ring size.

The ringbots are made of liquid crystal elastomers in the shape of looped ribbon, resembling a bracelet. When you place the ringbot on a surface that is at least 55 degrees Celsius (131 degrees Fahrenheit), which is hotter than the ambient air, the portion of the ribbon touching the surface contracts, while the portion of the ribbon exposed to the air does not. This induces a rolling motion in the ribbon. 

Similarly, when researchers shine infrared light on the ringbot, the portion of the ribbon exposed to the light contracts, while the portion shielded from the light does not. This also induces a rolling motion in the ribbon.

In practical terms, this means that the crawling ringbot moves from the bottom up when placed on a hot surface. But when exposed to infrared light, the movement begins from the top down.

One of the things that drives this continuous motion is the fact that the ringbots are bistable, meaning that there are two shapes when it is at rest. If the ribbon begins to twist, it will either snap back to its original shape, or snap forward into the other bistable state.

Sandia studies vulnerabilities of electric vehicle charging infrastructure

Kaedi Sanchez plugs in her car at a City of Albuquerque electric vehicle charger before heading to work. Sandia National Laboratories researchers have been studying the vulnerabilities of electric vehicle charging infrastructure, including public chargers, to better inform policymakers.
Photo Credit: Craig Fritz

With electric vehicles becoming more common, the risks and hazards of a cyber-attack on electric vehicle charging equipment and systems also increases. Jay Johnson, an electrical engineer at Sandia National Laboratories, has been studying the varied vulnerabilities of electric vehicle charging infrastructure for the past four years.

Johnson and his team recently published a summary of known electric vehicle charger vulnerabilities in the scientific journal Energies.

“By conducting this survey of electric vehicle charger vulnerabilities, we can prioritize recommendations to policymakers and notify them of what security improvements are needed by the industry,” Johnson said. “The Bipartisan Infrastructure Law allocates $7.5 billion to electric vehicle charging infrastructure. As a part of this funding, the federal government is requiring states to implement physical and cybersecurity strategies. We hope our review will help prioritize hardening requirements established by the states. Our work will also help the federal government standardize best practices and mandate minimum security levels for electric vehicle chargers in the future.”