New Superconducting Material For Levitating High-Speed Train or to Achieve Nuclear Fusion

In a historic achievement, University of Rochester researchers have created a superconducting material at both a temperature and pressure low enough for practical applications.

With this material, the dawn of ambient superconductivity and applied technologies has arrived,” according to a team led by Ranga Dias, an assistant professor of mechanical engineering and of physics. In a paper in Nature, the researchers describe a nitrogen-doped lutetium hydride (NDLH) that exhibits superconductivity at 69 degrees Fahrenheit (26 degrees Celsius) and 10 kilobars (145,000 pounds per square inch, or psi) of pressure.

Although 145,000 psi might still seem extraordinarily high (pressure at sea level is about 15 psi), strain engineering techniques routinely used in chip manufacturing, for example, incorporate materials held together by internal chemical pressures that are even higher.

Scientists have been pursuing this breakthrough in condensed matter physics for more than a century. Superconducting materials have two key properties: electrical resistance vanishes, and the magnetic fields that are expelled pass around the superconducting material. Such materials could enable:

  • Power grids that transmit electricity without the loss of up to 200 million megawatt hours (MWh) of the energy that now occurs due to resistance in the wires
  • Frictionless, levitating high-speed trains
  • More affordable medical imaging and scanning techniques such as MRI and magnetocardiography
  • Faster, more efficient electronics for digital logic and memory device technology
  • Tokamak machines that use magnetic fields to confine plasmas to achieve fusion as a source of unlimited power

Previously, the Dias team reported creating two materialscarbonaceous sulfur hydride and yttrium superhydride—that are superconducting at 58 degrees Fahrenheit (14,4 degrees Celsius) /39 million psi and 12 degrees Fahreneheit/26 million psi respectively, in papers in Nature and Physical Review Letters.


Sensitive Robotic Fingers

Although robotics has reshaped and even redefined many industrial sectors, there still exists a gap between machines and humans in fields such as health and elderly care. For robots to safely manipulate or interact with fragile objects and living organisms, new strategies to enhance their perception while making their parts softer are needed. In fact, building a safe and dexterous robotic gripper with human-like capabilities is currently one of the most important goals in robotics.

One of the main challenges in the design of soft robotic grippers is integrating traditional sensors onto the robot’s fingers. Ideally, a soft gripper should have what’s known as proprioception–a sense of its own movements and position–to be able to safely execute varied tasks. However, traditional sensors are rigid and compromise the mechanical characteristics of the soft parts. Moreover, existing soft grippers are usually designed with a single type of proprioceptive sensation; either pressure or finger curvature.

To overcome these limitations, scientists at Ritsumeikan University, Japan, have been working on novel soft gripper designs under the lead of Associate Professor Mengying Xie. In their latest study published in Nano Energy, they successfully used multimaterial 3D printing technology to fabricate soft robotic fingers with a built-in proprioception sensor. Their design strategy offers numerous advantages and represents a large step toward safer and more capable soft robots.

The use of multimaterial 3D printing, a simple and fast prototyping process, allowed the researchers to easily integrate the sensing and stiffness-tuning mechanisms into the design of the robotic finger itself.

Our work suggests a way of designing sensors that contribute not only as sensing elements for robotic applications, but also as active functional materials to provide better control of the whole system without compromising its dynamic behavior,” says Prof Xie. Another remarkable feature of their design is that the sensor is self-powered by the piezoelectric effect, meaning that it requires no energy supply–essential for low-power applications.


Artificial Skin Recreates The Human Sense Of Pain

Prosthetic technology has taken huge strides in the last decade, but accurately simulating human-like sensation is a difficult task. New “electronic skin” technology developed at the Daegu Gyeongbuk Institute of Science and Technology (DGIST) in Korea could help replicate advanced “pain” sensations in prosthetics, and enable robots to understand tactile feedback, like the feeling of being pricked, or that of heat on skin.

Trying to recreate the human senses has been a driver of technologies throughout the 20thcentury, like TV or audio playback. Mimicry of tactile sensing has been a focus of several different research groups in the last few years, but advances have mainly improved the feeling of pressure and strength in prosthetics. Human sensation, however, can detect much more subtle cues. The DGIST researchers, led by Department of Information and Communication Engineering Professor Jae Eun Jang, needed to bring together expertise from several different fields to begin the arduous task of replicating these more complex sensations in their electronic skin, working with colleagues in DGIST’s Robotics and Brain Sciences departments.

“We have developed a core base technology that can effectively detect pain, which is necessary for developing future-type tactile sensor. As an achievement of convergence research by experts in nano engineering, electronic engineering, robotics engineering, and brain sciences, it will be widely applied on electronic skin that feels various senses as well as new human-machine interactions.” Jang explained.

The DGIST team effort has created a more efficient sensor technology, able to simultaneously detect pressure and heat. They also developed a signal processing system that adjusted pain responses depending on pressure, area, and temperature.


Artificial Skin Opens SuperHuman Perception

A new type of sensor could lead to artificial skin that someday helps burn victimsfeel’ and safeguards the rest of us, University of Connecticut (UConn)  researchers suggest in a paper in Advanced Materials.

Our skin’s ability to perceive pressure, heat, cold, and vibration is a critical safety function that most people take for granted. But burn victims, those with prosthetic limbs, and others who have lost skin sensitivity for one reason or another, can’t take it for granted, and often injure themselves unintentionally. Chemists Islam Mosa from UConn, and James Rusling from UConn and UConn Health, along with University of Toronto engineer Abdelsalam Ahmed, wanted to create a sensor that can mimic the sensing properties of skin. Such a sensor would need to be able to detect pressure, temperature, and vibration. But perhaps it could do other things too, the researchers thought.

It would be very cool if it had abilities human skin does not; for example, the ability to detect magnetic fields, sound waves, and abnormal behaviors,” said Mosa.

Mosa and his colleagues created such a sensor with a silicone tube wrapped in a copper wire and filled with a special fluid made of tiny particles of iron oxide just one billionth of a meter long, called nanoparticles. The nanoparticles rub around the inside of the silicone tube and create an electric current. The copper wire surrounding the silicone tube picks up the current as a signal. When this tube is bumped by something experiencing pressure, the nanoparticles move and the electric signal changes. Sound waves also create waves in the nanoparticle fluid, and the electric signal changes in a different way than when the tube is bumped.

The researchers found that magnetic fields alter the signal too, in a way distinct from pressure or sound waves. Even a person moving around while carrying the sensor changes the electrical current, and the team found they could distinguish between the electrical signals caused by walking, running, jumping, and swimming.

Metal skin might sound like a superhero power, but this skin wouldn’t make the wearer Colossus from the X-men. Rather, Mosa and his colleagues hope it could help burn victimsfeelagain, and perhaps act as an early warning for workers exposed to dangerously high magnetic fields. Because the rubber exterior is completely sealed and waterproof, it could also serve as a wearable monitor to alert parents if their child fell into deep water in a pool, for example.