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Test equipment advancing to meet rapidly changing market needs

Although the rise of the IoT, 5G, and advanced automotive electronics markets is instigating rapid changes in technology, test equipment is keeping pace, and not just in extensions to bandwidth specifications or signal resolution. Maureen Lipps, Multicomp Pro Private Label Product Segment Leader, Test and Tools, Newark Electronics, runs through important advances in the industry and its tools.
Read the full article.

Smallest rugged AI supercomputer for avionics

Aitech Systems has released the A178-AV, the latest iteration of its smallest rugged GPGPU AI super-computers available with the powerful NVIDIA Jetson AGX Xavier System-on-Module. With its compact size, the A178-AV is the most advanced solution for artificial intelligence (AI), deep learning, and video and signal processing for next-gen avionic platforms.
Learn more.

Touchless angle sensors get CAN SAE J1939 interface

Novotechnik has added the CAN J1939 interface (developed for heavy-duty vehicles) to its RFC4800 Series of touchless angle sensors measuring angular position up to 360°, turn direction, turns, speed, and operational status. It can provide one or two output channels. It has a longer life and robustness than an optical encoder. It can signal if a sensor needs replacing or average a programmable number of values to output to reduce external noise if present. This is wear-free angle measurement made easy.
Learn more.

Radar level sensor monitors liquids and powders

The innovative FR Series non-contact radar level sensor from Keyence has been designed to monitor the level of both liquid and powder in any environment. This sensor features short- and long-range models, as well as chemical and sanitary options to address a wide array of level sensing applications. Works even when obstructions or harsh conditions are present, such as build-up, steam, or turbulence.
Learn more.

Raspberry Pi launches $70 AI Kit

Artificial intelligence (AI) is all the rage, and the makers of Raspberry Pi have created a way for enthusiasts of the single-board computer systems to take part and do a lot of experimenting along the way.
Read the full article.

3D model sharing at Brother Industries cuts rework

When Brother Industries, maker of printers, computers, and computer-related electronics, deployed Lattice Technology's XVL Player as a viewer for sharing 3D models throughout the processes of product design, parts design, mold design, mold production, and QA of molded parts, they reduced rework significantly -- especially from downstream departments. XVL Studio with its Difference Check Option helped address the rework in mold design, for example, by always keeping everyone informed of design changes.
Read this real-world case study.

What is 3D-MID? Molded parts with integrated electronics from HARTING

3D-MID (three-dimensional mechatronic integrated devices) technology combines electronic and mechanical functionalities into a single, 3D component. It replaces the traditional printed circuit board and opens up many new opportunities. It takes injection-molded parts and uses laser-direct structuring to etch areas of conductor structures, which are filled with a copper plating process to create very precise electronic circuits. HARTING, the technology's developer, says it's "Like a PCB, but 3D." Tons of possibilities.
Learn more (video included on page).

New! Thermoelectric dehumidifiers for enclosures

Seifert Systems has just introduced its line of compact Soliflex^® Series thermoelectric dehumidifiers, with or without condensate pump. These IP 56-rated units are designed to dehumidify enclosures and small control panels, can be used indoors or outdoors, and are maintenance free. When used with a hygrostat, Soliflex dehumidifiers will keep enclosure humidity below a defined level and only operate when needed.
Learn more.

More Stego enclosure heater options from AutomationDirect

Automation-Direct has added more Stego enclosure heaters to their Enclosure Thermal Management lineup. These new 120 to 240 VAC/VDC units include small, flat versions that distribute heat evenly within compact enclosures and are available with 8- or 10-W heating capacities. Also added are compact loop heaters that feature a patented loop body design for increased natural convection airflow, reduced thermal stress on the heater, and better heat transfer. Loop heaters are available in 10- to 150-W heating capacities.
Learn more.

Great design: Handle with integrated lighting/signaling

Signaling and indicator lights, switches, and buttons -- elements that hardly any machine can do without. The new JW Winco cabinet U-handle EN 6284 integrates all these functions into a single, compact element. The new U-handle is designed to enhance the operation of systems and machines. It features an integrated button and a large, colored, backlit area on the back of the handle. These elements can be used individually or in combination, providing a versatile tool for system control and process monitoring that can be seen from across the room.
Learn more.

Engineer's Toolbox: What is ground loop feedback?

Improper grounding can create problems in data logging, data acquisition, and measurement and control systems. One of the most common problems is known as ground loop feedback. Experts at CAS DataLoggers run through five ways to eliminate this problem.
Read the full article.

AI development kit for multi-camera products

The QCS6490 Vision-AI Development Kit from Avnet enables engineering teams to rapidly prototype hardware, application software, and AI enablement for multi-camera, high-performance, Edge AI-enabled custom embedded products. The kit facilitates design with the new, energy-efficient MSC SM2S-QCS6490 SMARC compute module based on the Qualcomm QCS6490 processor. Provides support for up to four MIPI CSI cameras and concurrent Mini DisplayPort and MIPI DSI displays.
Learn more.

High-temp cabinet cooler keeps incineration process in business

An EXAIR client company handles waste treatment on a large ship by operating an incinerator. The area where the incinerator is located gets very hot (over 120° F). This causes failures in the electronics package used to control the incineration process. Since compressed air is readily available, EXAIR's Model HT4225 Cabinet Cooler System is being used to keep the panel cool. It saved the customer from having to replace their control units due to the hot conditions in the incinerator room. Thermostat control is also available, conserving air and operating only when needed to minimize air consumption.
Learn about EXAIR's huge selection of Cabinet Coolers.

Compact snap-in capacitors for general-purpose applications

TDK's new EPCOS B43659 series of snap-in aluminum electrolytic capacitors is the next generation of ultra-compact, general-purpose components for voltages of 450 V (DC) featuring an extremely high CV product. It provides the same features and serves the same applications as the previous series but is much more compact. These RoHS-compliant capacitors can be used in a wide range of applications, such as switched-mode power supplies, frequency converters, UPS, medical equipment, and solar inverters.
Get all the specs.

Conductive Brush Ring overcomes current leakage in EV powertrains

SKF's new Conductive Brush Ring paves the way to greater reliability and longer life in high-performance electric vehicle powertrain systems. Using pure carbon fiber bristles, it provides a reliable electrical connection between an EV eAxle rotor shaft and its housing. When used in combination with SKF Hybrid ceramic ball bearings, it helps to alleviate parasitic current effects that can lead to premature failure in bearings and other components. Available in different configurations for wet (oil-lubricated) motor designs -- and soon for dry (sealed) applications.
Learn more.

New way to do solar power: Researchers boost efficiency and stability of optical rectennas

Georgia Tech researchers have developed a new higher efficiency rectenna design. Here, the device's ability to convert blue light to electricity is tested. [Credit: Christopher Moore, Georgia Tech]

 

 

By John Toon, Georgia Tech

The research team that announced the first optical rectenna in 2015 is now reporting a two-fold efficiency improvement in the devices -- and a switch to air-stable diode materials. The improvements could allow the rectennas, which convert electromagnetic fields at optical frequencies directly to electrical current, to operate low-power devices such as temperature sensors.

Ultimately, the researchers believe their device design, which is a combination of a carbon nanotube antenna and diode rectifier, could compete with conventional photovoltaic technologies for producing electricity from sunlight and other sources. The same technology used in the rectennas could also directly convert thermal energy to electricity.

"This work takes a significant leap forward in both fundamental understanding and practical efficiency for the optical rectenna device," said Baratunde Cola, an associate professor in the George W. Woodruff School of Mechanical Engineering at the Georgia Institute of Technology. "It opens up this technology to many more researchers who can join forces with us to advance the optical rectenna technology to help power a range of applications, including space flight."

The research was reported January 26 in the journal Advanced Electronic Materials. The work has been supported by the U.S. Army Research Office under the Young Investigator Program, and by the National Science Foundation.

Optical rectennas operate by coupling the light's electromagnetic field to an antenna, in this case an array of multiwall carbon nanotubes whose ends have been opened. The electromagnetic field creates an oscillation in the antenna, producing an alternating flow of electrons. When the electron flow reaches a peak at one end of the antenna, the diode closes, trapping the electrons, then re-opens to capture the next oscillation, creating a current flow.

Optical rectenna schematic: This schematic shows the components of the optical rectenna developed at the Georgia Institute of Technology. [Credit: Thomas Bougher, Georgia Tech]

 

 

The switching must occur at terahertz frequencies to match the light. The junction between the antenna and diode must provide minimal resistance to electrons flowing through it while open, yet prevent leakage while closed.

"The name of the game is maximizing the number of electrons that get excited in the carbon nanotube, and then having a switch that is fast enough to capture them at their peak," Cola explained. "The faster you switch, the more electrons you can catch on one side of the oscillation."

To provide a low work function (ease of electron flow), the researchers initially used calcium as the metal in their oxide insulator/metal diode junction. But calcium breaks down rapidly in air, meaning the device had to be encapsulated during operation -- and fabricated in a glovebox. That made the optical rectenna both impractical for most applications and difficult to fabricate.

So Cola, NSF Graduate Research Fellow Erik Anderson, and Research Engineer Thomas Bougher replaced the calcium with aluminum and tried a variety of oxide materials on the carbon nanotubes before settling on a bilayer material composed of alumina (Al2O3) and hafnium dioxide (HfO2). The combination coating for the carbon nanotube junction, created through an atomic deposition process, provides the quantum mechanical electron tunneling properties required by engineering the oxide electronic properties instead of the metals, which allows air stable metals with higher work functions than calcium to be used.

Rectennas fabricated with the new combination have remained functional for as long as a year. Other metal oxides could also be used, Cola said.

The researchers also engineered the slope of the hill down which the electrons fall in the tunneling process. That also helped increase the efficiency, and allows the use of a variety of oxide materials. The new design also increased the asymmetry of the diodes, which boosted efficiency.

"By working with the oxide electron affinity, we were able to increase the asymmetry by more than ten-fold, making this diode design more attractive," said Cola. "That's really where we got the efficiency gain in this new version of the device."

Optical rectennas could theoretically compete with photovoltaic materials for converting sunlight into electricity. PV materials operate using a different principle, in which photons knock electrons from the atoms of certain materials. The electrons are collected into electrical current.

In September 2015 in the journal Nature Nanotechnology, Cola and Bougher reported the first optical rectenna -- a device that had been proposed theoretically for more than 40 years, but never demonstrated.

The early version reported in the journal produced power at microvolt levels. The rectenna now produces power in the millivolt range, and conversion efficiency has gone from 10-5 to 10-3 -- still very low, but a significant gain.

"Though there still is room for significant improvement, this puts the voltage in the range where you could see optical rectennas operating low-power sensors," Cola said. "There are a lot of device geometry steps you could take to do something useful with the optical rectenna today in voltage-driven devices that don't require significant current."

Cola believes the rectennas could be useful for powering internet of things devices, especially if they can be used to produce electricity from scavenged thermal energy. For converting heat to electricity, the principle is the same as for light-capturing oscillations in a field with the broadband carbon nanotube antenna.

"People have been excited about thermoelectric generators, but there are many limitations on getting a system that works effectively," he said. "We believe that the rectenna technology will be the best approach for harvesting heat economically."

In future work, the research team hopes to optimize the antenna operation and improve their theoretical understanding of how the rectenna works, allowing further optimization. One day, Cola hopes the devices will help accelerate space travel, producing power for electric thrusters that will boost spacecraft.

"Our end game is to see carbon nanotube optical rectennas working on Mars and in the spacecraft that takes us to Mars," he said.

This work was supported by the Army Research Office under the Young Investigator Program agreement W911NF-13-1-0491 and the National Science Foundation Graduate Research Fellowship program under grant DGE-1650044.

Published March 2018

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