September 26, 2023 Volume 19 Issue 36

Electrical/Electronic News & Products

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Panasonic solar and EV components available from Newark

Newark has added Panasonic Industry's solar inverters and EV charging system components to their power portfolio. These best-in-class products help designers meet the growing global demand for sustainable and renewable energy mobility systems. Offerings include film capacitors, power inductors, anti-surge thick film chip resistors, graphite thermal interface materials, power relays, capacitors, and wireless modules.
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Standard parts with signal feedback included

JW Winco standard parts are becoming even more functional -- multifunctional, to be precise. From smart stop bolts that report whether workpieces are precisely positioned in the machining process to cabinet handles with signal lights and fluid level indicators with electronic REED contact signals, intelligent standard parts from JW Winco ensure greater safety, higher efficiency, and increased stability. Many more very useful options available for a wide range of applications.
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Create smarter control systems with relays

Control relays play a pivotal role in the world of automation and control systems. These versatile devices are designed to help you manage electrical circuits, making them indispensable for a wide range of applications. Learn the distinctive benefits of relays, including reliability and durability, versatility, ease of use, and costs. Check out the relays AA Electric has in stock too.
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COMSOL Multiphysics Version 6.2 is here

COMSOL Multiphysics Version 6.2 introduces faster solvers for turbulent fluid flow, electric motors, and room acoustics. It also brings data-driven surrogate model functionality for creating multiphysics-based digital twins and building fast and accurate standalone simulation apps. Get the full details of what's new in the latest version.
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17 ways SOLIDWORKS 2024 helps you work faster

SOLIDWORKS 2024 helps designers and engineers work faster than ever. Learn all about improvements to core 3D CAD modeling features, new 3D modeling techniques, and graphical and software performance boosts that will help you get your parts made and your products developed in record time.
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6 tips to streamline workflow in Mastercam 2024

Mastercam 2024 CAD/CAM software has been intentionally upgraded to make programming fast and easy. It prioritizes streamlining workflow so that the entire machining process -- from design to QC -- is as efficient as possible. Learn how to maximize the benefits of Mastercam 2024, including special toolpaths, easier hole-making operations, wireframe shortcuts, and more.
Read this informative Mastercam blog.


Leak detection sensor for multiple HVAC refrigerants

Sensata Technologies has launched the Sensata Resonix RGD sensor, the first leak detection sensor with UL certification for multiple A2L refrigerant gases used in heating, ventilation, and air conditioning (HVAC) equipment. It supports HVAC manufacturers' transition to refrigerants with a lower global warming impact. Typically mounted near the evaporator coil, the new sensor measures the acoustic resonance of the surrounding air in real time and can trigger mitigation, such as a fan, when A2L gas is detected.
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New electro-pneumatic vacuum regulator

The Type 1005V Electronic Vacuum Regulator is the first electronic vacuum regulator offered by ControlAir. It is used in various industrial and automation applications to precisely control and regulate the flow of air or gases in a system. It has two solenoid valves, a pressure sensor, and an electronic board for precise control to ensure that the vacuum pressure remains steady.
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Real-world applications: FUTEK 100 sensor examples

Get inspired. FUTEK has more than 100 real-world application examples for their load cells, force transducers, torque sensors, pressure sensors, and multi-axis sensors. From a cryogenic load cell on the Mars Curiosity rover to fly-by-wire multi-axis force and torque sensors for aircraft, learn about sensor systems, their specs, and design. Automotive, manufacturing, medical, robotics, and automation are covered too. Fascinating and highly practical.
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Filter fans for enclosures: 70 models in new series

The new 4000 Series from Seifert Systems covers 70 UL-listed filter fan models designed for enclosure applications. They snap in place once a cutout is made in the enclosure. Mounting screws are available with EMC models or as an option. Filter media snaps in place and easily slides out for replacement. When used with a Seifert thermostat, 4000 Series filter fans can be turned on only when needed. Air flow ranges from 7 to 483 cfm.
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What is 3D-MID? Molded parts with integrated electronics from HARTING

3D-MID (three-dimensional mechatronic integrated devices) tech 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.
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Need help with electronics connection design and manufacturing?

Conta-Clip combines electronics hardware and software development and production under one roof. Their comprehensive services range from simple-but-effective interface converters to complex control systems with touch displays and Ethernet connections. The company develops competitive connection solutions (including account costing) and closely cooperates with customers from needs analysis to prototype development, functional testing, series production, and even certification.
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Rugged sensor measures surface temperatures

TDK's tiny new T850 SMT NTC sensor measures surface temperatures for applications such as heat sinks of power modules and monitoring of industrial processes. It combines high humidity resistance with fast response time due to excellent thermal coupling to the target. The sensor is suitable for harsh environments with temps from -40 C to 150 C and is waterproof to 500 hrs.
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Inflatable EMI shielded RF enclosures

Saelig Company has introduced the Select Fabricators Series 700 EMI Enclosures -- reliable, portable, and lightweight RF and EMI shielding enclosures in standard sizes with a fast-up inflatable frame, ready for operation in less than 60 sec. No more aluminum tents. The Series 700 applies the same level of RF security obtained with previous RF/EMI shielded enclosures but is now made even more portable. Great for military operations, secure communications, mobile testing, emergency response, and more.
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Haptic feedback prototyping kit from TDK

Get your customers to feel the difference your products make. TDK has just released a development starter kit for fast haptics prototyping. It gives mechanical designers and engineers first impressions of the haptic feedback using PowerHap piezo actuators, shows how the mechanical integration works, and provides a reference design. Applications include automotive, displays and tablets, household appliances, vending machines, game controllers, industrial equipment, and medical devices.
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New device offers long-distance, low-power underwater communication

The system could be used for battery-free underwater communication across kilometer-scale distances to aid monitoring of climate and coastal change.

By Adam Zewe, MIT News

MIT researchers have demonstrated the first system for ultra-low-power underwater networking and communication that can transmit signals across kilometer-scale distances.

This technique, which the researchers began developing several years ago, uses about one-millionth the power that existing underwater communication methods use. By expanding their battery-free system's communication range, the researchers have made the technology more feasible for applications such as aquaculture, coastal hurricane prediction, and climate change modeling.

"What started as a very exciting intellectual idea a few years ago -- underwater communication with a million times lower power -- is now practical and realistic. There are still a few interesting technical challenges to address, but there is a clear path from where we are now to deployment," says Fadel Adib, associate professor in the Department of Electrical Engineering and Computer Science and director of the Signal Kinetics group in the MIT Media Lab.

The new device is an array of piezoelectric transducers that enables battery-free underwater communication. [Credit: Courtesy of the researchers]

 

 

Underwater backscatter enables low-power communication by encoding data in sound waves that it reflects, or scatters, back toward a receiver. These innovations enable reflected signals to be more precisely directed at their source.

Due to this "retrodirectivity," less signal scatters in the wrong directions, allowing for more efficient and longer-range communication.

When tested in a river and an ocean, the retrodirective device exhibited a communication range that was more than 15 times farther than previous devices. However, the experiments were limited by the length of the docks available to the researchers.

To better understand the limits of underwater backscatter, the team also developed an analytical model to predict the technology's maximum range. The model, which they validated using experimental data, showed that their retrodirective system could communicate across kilometer-scale distances.

The researchers shared these findings in two papers which will be presented at this year's ACM SIGCOMM and MobiCom conferences. Adib, senior author on both papers, is joined on the SIGCOMM paper by co-lead authors Aline Eid, a former postdoc who is now an assistant professor at the University of Michigan, and Jack Rademacher, a research assistant; as well as research assistants Waleed Akbar and Purui Wang, and postdoc Ahmed Allam. The MobiCom paper is also written by co-lead authors Akbar and Allam.

Communicating with sound waves
Underwater backscatter communication devices utilize an array of nodes made from "piezoelectric" materials to receive and reflect sound waves. These materials produce an electric signal when mechanical force is applied to them.

When sound waves strike the nodes, they vibrate and convert the mechanical energy to an electric charge. The nodes use that charge to scatter some of the acoustic energy back to the source, transmitting data that a receiver decodes based on the sequence of reflections.

However, because the backscattered signal travels in all directions, only a small fraction reaches the source, reducing the signal strength and limiting the communication range.

To overcome this challenge, the researchers leveraged a 70-year-old radio device called a Van Atta array, in which symmetric pairs of antennas are connected in such a way that the array reflects energy back in the direction it came from.

However, connecting piezoelectric nodes to make a Van Atta array reduces their efficiency. The researchers avoided this problem by placing a transformer between pairs of connected nodes. The transformer, which transfers electric energy from one circuit to another, allows the nodes to reflect the maximum amount of energy back to the source.

"Both nodes are receiving and both nodes are reflecting, so it is a very interesting system. As you increase the number of elements in that system, you build an array that allows you to achieve much longer communication ranges," Eid explains.

In addition, they used a technique called cross-polarity switching to encode binary data in the reflected signal. Each node has a positive and a negative terminal (like a car battery), so when the positive terminals of two nodes are connected and the negative terminals of two nodes are connected, that reflected signal is a "bit one."

But if the researchers switch the polarity, and the negative and positive terminals are connected to each other instead, then the reflection is a "bit zero."

"Just connecting the piezoelectric nodes together is not enough. By alternating the polarities between the two nodes, we are able to transmit data back to the remote receiver," Rademacher explains.

When building the Van Atta array, the researchers found that if the connected nodes were too close, they would block each other's signals. They devised a new design with staggered nodes that enables signals to reach the array from any direction. With this scalable design, the more nodes an array has, the greater its communication range.

They tested the array in more than 1,500 experimental trials in the Charles River in Cambridge, MA, and in the Atlantic Ocean, off the coast of Falmouth, MA, in collaboration with the Woods Hole Oceanographic Institution. The device achieved communication ranges of 300 m, more than 15 times longer than they previously demonstrated.

However, they had to cut the experiments short, because they ran out of space on the dock.

Modeling the maximum
That inspired the researchers to build an analytical model to determine the theoretical and practical communication limits of this new underwater backscatter technology.

Building off their group's work on RFIDs, the team carefully crafted a model that captured the impact of system parameters, like the size of the piezoelectric nodes and the input power of the signal, on the underwater operation range of the device.

"It is not a traditional communication technology, so you need to understand how you can quantify the reflection. What are the roles of the different components in that process?" Akbar says.

For instance, the researchers needed to derive a function that captures the amount of signal reflected out of an underwater piezoelectric node with a specific size, which was among the biggest challenges of developing the model, he adds.

They used these insights to create a plug-and-play model into which a user could enter information like input power and piezoelectric node dimensions and receive an output that shows the expected range of the system.

They evaluated the model on data from their experimental trials and found that it could accurately predict the range of retrodirected acoustic signals with an average error of less than one decibel.

Using this model, they showed that an underwater backscatter array can potentially achieve kilometer-long communication ranges.

"We are creating a new ocean technology and propelling it into the realm of the things we have been doing for 6G cellular networks. For us, it is very rewarding, because we are starting to see this now very close to reality," Adib says.

The researchers plan to continue studying underwater backscatter Van Atta arrays, perhaps using boats so they could evaluate longer communication ranges. Along the way, they intend to release tools and datasets so other researchers can build on their work. At the same time, they are beginning to move toward commercialization of this technology.

Read: "Enabling Long-Range Underwater Backscatter via Van Atta Acoustic Networks" and "The Underwater Backscatter Channel: Theory, Link Budget, and Experimental Validation"

Published September 2023

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