'Squid Skin' Metamaterial Yields Vivid Color Display

The quest to create artificial "squid skin" — camouflaging metamaterials that can "see" colors and automatically blend into the background — is one step closer to reality, thanks to a color-display technology by Rice University's Laboratory for Nanophotonics (LANP).The new full-color display technology uses aluminum nanoparticles to create the vivid red, blue, and green hues found in today's top-of-the-line LCD televisions and monitors.The breakthrough is the latest in a string of recent discoveries by a Rice-led team that set out in 2010 to create metamaterials capable of mimicking the camouflage abilities of cephalopods — the family of marine creatures that includes squid, octopus, and cuttlefish.LANP's new color display technology delivers bright red, blue, and green hues from five-micron-square pixels that each contains several hundred aluminum nanorods. By varying the length of the nanorods and the spacing between them, LANP researchers Stephan Link and Jana Olson showed they could create pixels that produced dozens of colors, including rich tones of red, green, and blue that are comparable to those found in high-definition LCD displays.

Posted in: Imaging, Displays/Monitors/HMIs, Materials, Nanotechnology, News


Untethered Soft Robot Walks Through Flames

Developers from Harvard’s School of Engineering and Applied Sciences and the Wyss Institute for Biologically Inspired Engineering have produced the first untethered soft robot — a quadruped that can stand up and walk away from its designers.The researchers were able to scale up earlier soft-robot designs, enabling a single robot to carry on its back all the equipment it needs to operate — micro-compressors, control systems, and batteries.Compared with earlier soft robots, which were typically no larger than a steno pad, the system is huge, measuring more than a half-meter in length and capable of carrying as much as 7½ pounds on its back.Giving the untethered robot the strength needed to carry mechanical components meant air pressures as high as 16 pounds per square inch, more than double the seven psi used by many earlier robot designs. To deal with the increased pressure, the robot had to be made of tougher stuff.The material settled on was a “composite” silicone rubber made from stiff rubber impregnated with hollow glass microspheres to reduce the robot’s weight. The robot’s bottom was made from Kevlar fabric to ensure it was tough and lightweight. The result was a robot that can stand up to a host of extreme conditions.SourceAlso: Learn about a Field-Reconfigurable Manipulator for Rovers.

Posted in: Materials, Composites, Mechanical Components, Motion Control, Motors & Drives, Machinery & Automation, Robotics, News


Researchers Create See-Through Solar Concentrator

A team of researchers at Michigan State University has developed a new type of solar concentrator that when placed over a window creates solar energy.The device is called a transparent luminescent solar concentrator and can be used on buildings, cell phones, and any other device that has a clear surface.And, according to Richard Lunt of MSU’s College of Engineering, the key word is “transparent.”The solar harvesting system uses small organic molecules developed by Lunt and his team to absorb specific nonvisible wavelengths of sunlight.The “glowing” infrared light is guided to the edge of the plastic where it is converted to electricity by thin strips of photovoltaic solar cells.“Because the materials do not absorb or emit light in the visible spectrum, they look exceptionally transparent to the human eye,” said Richard Lunt of MSU’s College of Engineering.SourceAlso: Learn about High-Efficiency Nested Hall Thrusters for Robotic Solar System Exploration.

Posted in: Materials, Plastics, Solar Power, Renewable Energy, Energy, Semiconductors & ICs, News


Water Splitter Runs on AAA Battery

Scientists at Stanford University have developed a low-cost, emissions-free device that uses an ordinary AAA battery to produce hydrogen by water electrolysis.  The battery sends an electric current through two electrodes that split liquid water into hydrogen and oxygen gas. Unlike other water splitters that use precious-metal catalysts, the electrodes in the Stanford device are made of inexpensive and abundant nickel and iron.In addition to producing hydrogen, the novel water splitter could be used to make chlorine gas and sodium hydroxide, an important industrial chemical. Splitting water to make hydrogen requires no fossil fuels and emits no greenhouse gases. But scientists have yet to develop an affordable, active water splitter with catalysts capable of working at industrial scales."It's been a constant pursuit for decades to make low-cost electrocatalysts with high activity and long durability," said Stanford University Professor Hongjie Dai. "When we found out that a nickel-based catalyst is as effective as platinum, it came as a complete surprise."SourceAlso: Learn about a Proton Exchange Membrane Fuel Cell.

Posted in: Batteries, Electronics & Computers, Power Management, Alternative Fuels, Green Design & Manufacturing, Materials, Metals, Energy, News


Researchers Create Energy-Absorbing Material

Materials like solid gels and porous foams are used for padding and cushioning, but each has its own advantages and limitations.A team of engineers and scientists at Lawrence Livermore National Laboratory (LLNL) has found a way to design and fabricate, at the microscale, new cushioning materials with a broad range of programmable properties and behaviors that exceed the limitations of the material's composition, through additive manufacturing, also known as 3D printing. Livermore researchers, led by engineer Eric Duoss and scientist Tom Wilson, focused on creating a micro-architected cushion using a silicone-based ink that cures to form a rubber-like material after printing. During the printing process, the ink is deposited as a series of horizontally aligned filaments (which can be fine as a human hair) in a single layer. The second layer of filaments is then placed in the vertical direction. This process repeats itself until the desired height and pore structure is reached.The researchers envision using their novel energy-absorbing materials in many applications, including shoe and helmet inserts, protective materials for sensitive instrumentation, and in aerospace applications to combat the effects of temperature fluctuations and vibration.SourceAlso: Read more Materials tech briefs.

Posted in: Manufacturing & Prototyping, Rapid Prototyping & Tooling, Materials, Aerospace, Defense, News


NASA 3D Printing Technique Creates Metal Spacecraft Parts

Researchers at NASA's Jet Propulsion Laboratory are implementing a printing process that transitions from one metal or alloy to another in a single object. JPL scientists have been developing a technique to address this problem since 2010. An effort to improve the methods of combining parts made of different materials in NASA's Mars Science Laboratory mission inspired a project to 3D print components with multiple alloy compositions.

Posted in: Manufacturing & Prototyping, Rapid Prototyping & Tooling, Materials, Metals, Aerospace, News


Secret of Eumelanin’s Ability to Absorb Broad Spectrum of Light Uncovered

Melanin — and specifically, the form called eumelanin — is the primary pigment that gives humans the coloring of their skin, hair, and eyes. It protects the body from the hazards of ultraviolet and other radiation that can damage cells and lead to skin cancer. But the exact reason why the compound is so effective at blocking such a broad spectrum of sunlight has remained something of a mystery. Now, however, researchers at MIT and other institutions have solved that mystery, potentially opening the way for the development of synthetic materials that could have similar light-blocking properties.

Posted in: Electronics & Computers, Photonics, Optics, Materials, Composites, Medical, Solar Power, Energy, News