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Test your knowledge: High-temp adhesives

Put your knowledge to the test by trying to answer these key questions on how to choose the right high-temperature-resistant adhesive. The technical experts from Master Bond cover critical information necessary for the selection process, including questions on glass transition temperature and service temperature range. Some of the answers may surprise even the savviest of engineers.
Take the quiz.

New Air Holster Safety Air Gun Mount

EXAIR's new Model 5930 Air Holster provides a simple and convenient way to keep Safety Air Guns secure and within easy reach at workstations throughout a facility. Designed to give operators a designated location for their air gun when not in use, the Air Holster helps prevent misplaced tools while keeping work areas organized and efficient. Its practical design makes it an ideal addition to manufacturing, assembly, maintenance, and other industrial workstations where Safety Air Guns are frequently used.
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Southco access hardware in rail applications

Discover how Southco's rail access hardware solutions help improve safety, reliability, and operational efficiency across modern rail networks. The video showcases a range of rail applications where Southco's access hardware plays a critical role, including driver cabins, lighting systems, tray tables, headrests, armrests, and other passenger and operator touchpoints. Designed to support dependable performance in demanding moving environments, Southco's solutions help operators streamline maintenance processes, minimize downtime, and enable more proactive asset management.
View the video.

Multi-zone tension leveler for hard-to-flatten alloys

Redex USA's Levelflex^® is a modular, multi-zone tension leveler engineered for continuous processing lines, including coating and heat treatment of aluminum alloys and where flatness is critical to coating adhesion and downstream formability. By stretching material within 95% of its yield strength, it corrects stubborn flatness defects in fewer passes. It comes in open-loop pure stretch or closed-loop tension measurement modes to optimize surface integrity and eliminate crossbow.
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Hold any shape with ID and OD Form Holding Clamps

These simple OD and ID clamping solutions from Fixtureworks clamp onto your part in one easy operation, eliminating the need for custom fixtures. They allow users to clamp onto the inner or outer diameter of small-size, irregularly shaped work parts fast. Lots of options.
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Need inserts? We make it E-Z.

Founded in 1956, E-Z LOK allows users to repair damaged or worn-out threads without the need for special taps or installation tools. Our line of threaded locking inserts is used in metal, plastic, wood, composite, and additive industries. Extensive inventories are maintained in four warehouses across the U.S., and all products are sold through industrial distributors. One source for all your needs!
Learn more
or contact Kyle Lindsly-Roach for free samples at 310.323.5613 x221.

Stop paying the 'assembly tax': Why your next design should be one part not 10

"As metal additive manufacturing (AM) moves from the prototyping lab to mainline production, the most significant ROI isn't found in making parts faster, it's found in making fewer of them." So says Erica Manzella of Go Engineer. Learn about the hidden costs of traditional assembly, the DfAM toolset native to SOLIDWORKS, and the advanced 3DEXPERIENCE optimization tools and industrial metal AM hardware that are making monolithic design a physical reality.
Read the GoEngineer blog.

Best-seller: Copper filament for 3D printing

Virtual Foundry, the company that brought us 3D-printable lunar regolith simulant, says Copper Filamet™ (not a typo) is its best-selling metal filament. This material is compatible with any open-architecture FDM/FFF 3D printer. After sintering, final parts are 100% pure copper. The company says this is one of the easiest materials to print and sinter. Stainless steel, porcelain, aluminum, and titanium available too.
Learn more and get all the specs.

What can replace a coil spring? You've got better options!

Traditional coil springs can limit mechanical designs. Wave springs offer a space-saving alternative, providing equivalent force and deflection in up to half the operating height while reducing assembly size and weight. There are four wave spring types that can replace a coil spring. Learn how each variant delivers unique performance capabilities to optimize space, efficiency, and reliability.
Read this informative NEW Smalley technical article.

Next-gen metal bonding: 3M Scotch-Weld 8500 Series

Replace traditional fasteners and streamline assembly with 3M Scotch-Weld Acrylic Adhesive DP8507NS. Engineered for direct bonding to bare or slightly oily metals with minimal surface prep, this high-performance adhesive withstands paint bake cycles up to 200 C (392 F), resists corrosion, and holds strong down to -40 C. Upgrade durability, aesthetics, and design flexibility. Bonds many plastics too!
View the video.

3 things you need to get right when 3D printing gears

When businesses decide to 3D print their own gears, they can reduce lead times and costs associated with replacements, prototypes, and small-batch production runs significantly. According to the experts at igus, however, "achieving industrial-grade reliability requires more than just a digital file; there are several fundamental technical basics you must master first to ensure your gears can withstand the rigors of real-world use."
Read this informative igus tech tip.

DURACON polymer with 30% recycled content

Daicel Corporation's High Performance Polymers SBU has launched four new DURACON^® POM grades featuring 30% post-consumer recycled (PCR) content. Unveiled at CHINAPLAS 2026, the lineup includes Standard, Low VOC, Sliding, and Tough options. Leveraging advanced compounding expertise, Daicel maintains quality and mechanical performance comparable to standard virgin resin grades for demanding global industrial and automotive components.
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Renishaw unveils revolutionary LIBERTAS™ 3DP tech

Renishaw's new LIBERTAS software technology addresses two of the most persistent challenges in metal AM: poor downskin surface finish and the need for support structures. Users have greater freedom to manufacture complex geometries.
Read the full article.

Innovate like a PRO: Protolabs' new AI-enabled manufacturing platform

ProDesk by Protolabs accelerates innovation for product development and procurement teams. It features real-time, AI-powered quoting with design for manufacturability (DFM) analysis across injection molding, CNC machining, and 3D printing. The platform enables seamless team collaboration and customizes quotes with instant feedback on materials, lead times, secondary operations, and finishes prior to production.
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SDP/SI Shaftloc Fastening System

Shaftloc is a unique, reusable locking device for securely mounting mechanical components like gears and sprockets onto shafts without the need for keyways, set screws, or adhesives. Its simple, two-piece design offers a cost-effective alternative to traditional fasteners, providing high clamping force and vibration resistance. Installed with standard tools, Shaftloc is perfect for designers seeking flexible, hubless mounting solutions. Available in four styles.
Learn more from SDP/SI.

Drones relay RFID signals for inventory control

A new system developed by MIT researchers enables small, safe aerial drones to read RFID tags in large warehouses at a distance of several meters.

 

 

By Larry Hardesty, MIT

Radio frequency ID tags were supposed to revolutionize supply chain management. The dirt-cheap, battery-free tags, which receive power wirelessly from scanners and then broadcast identifying numbers, enable warehouse managers to log inventory much more efficiently than they could by reading box numbers and recording them manually.

But the scale of modern retail operations makes even radio frequency ID (RFID) scanning inefficient. Walmart, for instance, reported that in 2013 it lost $3 billion in revenue because of mismatches between its inventory records and its stock. Even with RFID technology, it can take a single large retail store three months to perform a complete inventory review, which means that mismatches often go undiscovered until exposed by a customer request.

MIT researchers have now developed a system that enables small, safe aerial drones to read RFID tags from tens of meters away while identifying the tags' locations with an average error of about 19 cm. The researchers envision that the system could be used in large warehouses for both continuous monitoring, to prevent inventory mismatches, and location of individual items, so that employees can rapidly and reliably meet customer requests.

The central challenge in designing the system was that, with the current state of autonomous navigation, the only drones safe enough to fly within close range of humans are small, lightweight drones with plastic rotors, which wouldn't cause injuries in the event of a collision. But those drones are too small to carry RFID readers with a range of more than a few centimeters.

The researchers met this challenge by using the drones to relay signals emitted by a standard RFID reader. This not only solves the safety problem but also means that drones could be deployed in conjunction with existing RFID inventory systems, without the need for new tags, readers, or reader software.

"Between 2003 and 2011, the U.S. Army lost track of $5.8 billion of supplies among its warehouses," says Fadel Adib, the Sony Corporation Career Development Assistant Professor of Media Arts and Sciences, whose group at the MIT Media Lab developed the new system. "In 2016, the U.S. National Retail Federation reported that shrinkage -- loss of items in retail stores -- averaged around $45.2 billion annually. By enabling drones to find and localize items and equipment, this research will provide a fundamental technological advancement for solving these problems."

VIDEO: RFly: Drones that find missing objects using battery-free RFIDs.

The MIT researchers describe their system, dubbed RFly, in a paper they presented at the end of August at the annual conference of the Association for Computing Machinery's Special Interest Group on Data Communications. Adib is the senior author on the paper, and he's joined by Yunfei Ma, a postdoc in the Media Lab, and Nicholas Selby, an MIT graduate student in mechanical engineering.

Phase shift
Relaying RFID signals and using them to determine tags' locations poses some thorny signal-processing problems. One is that, because the RFID tag is powered wirelessly by the reader, the reader and the tag transmit simultaneously at the same frequency. A relay system adds another pair of simultaneous transmissions: two between the relay and the tag and two between the relay and the reader. That's four simultaneous transmissions at the same frequency, all interfering with each other.

This problem is compounded by the requirement that the system determine the location of the RFID tag. The location-detection -- or "localization" -- system uses a variation on a device called an antenna array. If several antennas are clustered together, a signal broadcast toward them at an angle will reach each antenna at a slightly different time. That means that the signals detected by the antennas will be slightly out of phase: The troughs and crests of their electromagnetic waves won't coincide perfectly. From those phase differences, software can deduce the angle of transmission and thus the location of the transmitter.

The drone is too small to carry an array of antennas, but it is continuously moving, so readings it takes at different times are also taken at different locations, simulating the multiple antenna elements of an array.

Ordinarily, to combat interference, the drone would digitally decode the transmission it receives from the tag and re-encode it for transmission to the reader. But in this case, the delays imposed by the decoding-encoding process would change the signals' relative phases, making it impossible to accurately gauge location.

All radio systems encode information by modulating a base transmission frequency, usually by shifting it slightly up and down. But because an RFID tag has no independent power source, its modulations are detectably smaller than those of the reader. So the MIT researchers devised an analog filter that would subtract the base transmission frequency from the signals that reach the reader and then separate the low-frequency and high-frequency components. The low-frequency component -- the signal from the tag -- is then added back onto the base frequency.

Frame of reference
At this point, however, another problem still remains. Because the drone is moving, the phase shift of the signals that reach the reader result from not only the drone's position relative to the RFID tag but also its position relative to the reader. On the basis of the received signal alone, the reader has no way to tell how much each of those two factors contributed to the total phase shift.

So the MIT researchers also equip each of their drones with its own RFID tag. A drone alternates between relaying the reader's signal to a tagged item and simply letting its own tag reflect the signal back, so that the reader can estimate the drone's contribution to the total phase shift and remove it.

In experiments in the Media Lab that involved tagged objects, many of which were intentionally hidden to approximate the condition of merchandise heaped in piles on warehouse shelves, the system was able to localize the tags with 19-cm accuracy while extending the range of the reader tenfold in all directions, or one hundredfold cumulatively. The researchers are currently conducting a second set of experiments in the warehouse of a major Massachusetts retailer.

"Relays have been used in communications for a long time, even to bring networks to rural areas," says Swarun Kumar, an assistant professor of electrical and computer engineering at Carnegie Mellon University. "What changes here is that one of the ends is battery-free, and they want to location-track the battery-free device, which requires phase-consistent measurements. These together make the problem quite challenging. That's what I think is the conceptual novelty in this work. I anticipate that there might be a lot more applications than the inventory tracking problem -- which in and of itself is quite important."

Published October 2017

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