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Intro to reed switches, magnets, magnetic fields

This brief introductory video on the DigiKey site offers tips for engineers designing with reed switches. Dr. Stephen Day, Ph.D. from Coto Technology gives a solid overview on reed switches -- complete with real-world application examples -- and a detailed explanation of how they react to magnetic fields.
View the video.

Bi-color LEDs to light up your designs

Created with engineers and OEMs in mind, SpectraBright Series SMD RGB and Bi-Color LEDs from Visual Communi-cations Company (VCC) deliver efficiency, design flexibility, and control for devices in a range of industries, including mil-aero, automated guided vehicles, EV charging stations, industrial, telecom, IoT/smart home, and medical. These 50,000-hr bi-color and RGB options save money and space on the HMI, communicating two or three operating modes in a single component.
Learn more.

All about slip rings: How they work and their uses

Rotary Systems has put together a really nice basic primer on slip rings -- electrical collectors that carry a current from a stationary wire into a rotating device. Common uses are for power, proximity switches, strain gauges, video, and Ethernet signal transmission. This introduction also covers how to specify, assembly types, and interface requirements. Rotary Systems also manufactures rotary unions for fluid applications.
Read the overview.

Seifert thermoelectric coolers from AutomationDirect

Automation-Direct has added new high-quality and efficient stainless steel Seifert 340 BTU/H thermoelectric coolers with 120-V and 230-V power options. Thermoelectric coolers from Seifert use the Peltier Effect to create a temperature difference between the internal and ambient heat sinks, making internal air cooler while dissipating heat into the external environment. Fans assist the convective heat transfer from the heat sinks, which are optimized for maximum flow.
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EMI shielding honeycomb air vent panel design

Learn from the engineering experts at Parker how honeycomb air vent panels are used to help cool electronics with airflow while maintaining electromagnetic interference (EMI) shielding. Topics include: design features, cell size and thickness, platings and coatings, and a stacked design called OMNI CELL construction. These vents can be incorporated into enclosures where EMI radiation and susceptibility is a concern or where heat dissipation is necessary. Lots of good info.
Read the Parker blog.

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.
View the video.

Loss-free conversion of 3D/CAD data

CT CoreTech-nologie has further developed its state-of-the-art CAD converter 3D_Evolution and is now introducing native interfaces for reading Solidedge and writing Nx and Solidworks files. It supports a wide range of formats such as Catia, Nx, Creo, Solidworks, Solidedge, Inventor, Step, and Jt, facilitating smooth interoperability between different systems and collaboration for engineers and designers in development environments with different CAD systems.
Learn more.

Top 5 reasons for solder joint failure

Solder joint reliability is often a pain point in the design of an electronic system. According to Tyler Ferris at ANSYS, a wide variety of factors affect joint reliability, and any one of them can drastically reduce joint lifetime. Properly identifying and mitigating potential causes during the design and manufacturing process can prevent costly and difficult-to-solve problems later in a product lifecycle.
Read this informative ANSYS blog.

Advanced overtemp detection for EV battery packs

Littelfuse has introduced TTape, a ground-breaking over-temperature detection platform designed to transform the management of Li-ion battery systems. TTape helps vehicle systems monitor and manage premature cell aging effectively while reducing the risks associated with thermal runaway incidents. This solution is ideally suited for a wide range of applications, including automotive EV/HEVs, commercial vehicles, and energy storage systems.
Learn more.

Benchtop ionizer for hands-free static elimination

EXAIR's Varistat Benchtop Ionizer is the latest solution for neutralizing static on charged surfaces in industrial settings. Using ionizing technology, the Varistat provides a hands-free solution that requires no compressed air. Easily mounted on benchtops or machines, it is manually adjustable and perfect for processes needing comprehensive coverage such as part assembly, web cleaning, printing, and more.
Learn more.

LED light bars from AutomationDirect

Automation-Direct adds CCEA TRACK-ALPHA-PRO series LED light bars to expand their offering of industrial LED fixtures. Their rugged industrial-grade anodized aluminum construction makes TRACKALPHA-PRO ideal for use with medium to large-size industrial machine tools and for use in wet environments. These 120 VAC-rated, high-power LED lights provide intense, uniform lighting, with up to a 4,600-lumen output (100 lumens per watt). They come with a standard bracket mount that allows for angle adjustments. Optional TACLIP mounts (sold separately) provide for extra sturdy, vibration-resistant installations.
Learn more.

World's first metalens fisheye camera

2Pi Optics has begun commercial-ization of the first fisheye camera based on the company's proprietary metalens technology -- a breakthrough for electronics design engineers and product managers striving to miniaturize the tiny digital cameras used in advanced driver-assistance systems (ADAS), AR/VR, UAVs, robotics, and other industrial applications. This camera can operate at different wavelengths -- from visible, to near IR, to longer IR -- and is claimed to "outperform conventional refractive, wide-FOV optics in all areas: size, weight, performance, and cost."
Learn more.

Orbex offers two fiber optic rotary joint solutions

Orbex Group announces its 700 Series of fiber optic rotary joint (FORJ) assemblies, supporting either single or multi-mode operation ideal for high-speed digital transmission over long distances. Wavelengths available are 1,310 or 1,550 nm. Applications include marine cable reels, wind turbines, robotics, and high-def video transmission. Both options feature an outer diameter of 7 mm for installation in tight spaces. Construction includes a stainless steel housing.
Learn more.

Mini tunnel magneto-resistance effect sensors

Littelfuse has released its highly anticipated 54100 and 54140 mini Tunnel Magneto-Resistance (TMR) effect sensors, offering unmatched sensitivity and power efficiency. The key differentiator is their remarkable sensitivity and 100x improvement in power efficiency compared to Hall Effect sensors. They are well suited for applications in position and limit sensing, RPM measurement, brushless DC motor commutation, and more in various markets including appliances, home and building automation, and the industrial sectors.
Learn more.

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.
Learn more.

Army offers look inside its projectile-catching SCat test system

By Eric Kowal, The Picatinny Voice

An overhead view of the Soft Catch (SCat) Recovery System firing a projectile.

 

 

Why would the U.S. Army want to fire a 155-mm projectile into 540 ft of steel catch tubes (called the Soft Catch (SCat) Recovery System) and then recover the projectile at the other end?

The answer is actually quite simple: It saves time, money, and helps to develop better products.

First, the forces the projectile experiences from being fired from a cannon tube can be recorded using on-board-recorders, which help engineers design robust and reliable precision munition systems and components.

That information is then transferred to a computer, analyzed, and provides valuable feedback to engineers and warfighters to help in the future development of weapons and munitions systems.

Second, the SCat Gun System saves money. Engineers can either catch the round and easily recover it within minutes at Picatinny Arsenal or traipse through the desert in Arizona looking for the round they just fired.

Without the Soft Recovery System facility and the Soft Catch Gun capability, the costs associated with weaponizing advanced technology increase to the point where programs are managed at high risk to fit within allocated budgets.

The SCat facility is owned and operated by the U.S. Army Armament Research, Development, and Engineering Center (ARDEC) and dovetails with the organization's mission.

Development programs such as the Excalibur precision ammunition and Precision Guidance Kits can use such a system for ongoing development, thus reducing development cycle time and cost.

"This is here to soft-catch projectiles so that we can tear them apart after we have fired them to determine what has or has not survived," says Robert Marchak, a mechanical engineer in the Fuze Division of the Munitions Engineering Technology Center.

"We are trying to increase the reliability of smart munitions when we give them to the Soldier," he says.

The system is comprised of a 155-mm Howitzer weapon with a M199 gun tube and 540 ft of catch tubes.

This is a hybrid system that uses both pressurized air and water to help slow down the projectile's momentum. It is the only system of its kind in the world.

The first part of the chain of catch tubes only contains atmospheric air. The next section, 320 ft of the tubes, contains pressurized air, followed by an 80-ft section filled with water.

A small burst diaphragm seals one end of the pressurized air, and a piston seals the other end.

The piston also separates the water and pressurized air sections. The burst diaphragm and piston are replaced after each test fire.

Once fired, the projectile achieves free flight for approximately 6 ft and travels down the catch tubes, generating shockwaves that interact with the atmospheric air section, the burst diaphragm, the pressurized air section, the piston, and the water section.

In a little over 1 sec, the projectile shockwaves break the burst diaphragm. The air section is compressed and pushed forward, shock and pressure shear the piston moving it against the water (momentum transfer), all while slowing the projectile to a stop.

The piston is ejected out of the end of the system, followed by the air and water, and finally the projectile comes to rest in a mechanized brake system.

On-board recorders inside the projectile measure the accelerations of the projectile from the gun-launch and the catch events.

[Image courtesy: U.S. Army RDECOM]

 

 

With a muzzle velocity of 888 m/sec, the entire test takes a little over 1 sec from the time the projectile is fired until it has completely stopped.

The speed of 888 m/sec is equal to 1,986 mph. If a commuter plane could travel at that speed, passengers could fly from Picatinny Arsenal in New Jersey to Albuquerque, NM, in 1 hr.

The catch tubes are made of the same steel used to manufacture the 155-mm gun tube.

What makes this system attractive is the tight fit achieved just over the projectile bourlette diameter. This helps keep the projectile straight and makes for a smooth ride.

In addition, the system was designed to quickly remove and replace broken parts. Having the capability to quickly turn the system around after part failures is critical in maintaining an ongoing testing capability, which in turn helps weapons programs stay on schedule.

Since the system is entirely made of metal, temperature fluctuations cause the system to expand with heat and contract when cold.

The system was designed to remain straight, yet have the ability to move in the axial direction during these temperature changes; otherwise, if completely fixed, the stresses caused by contractions or expansions could break bolts or other critical parts on the system.

"This whole system during the winter to summer months can grow or shrink about two inches on any given day," Marchak says.

The speed and or velocity of the projectile can be controlled by the energetic operator using a pre-determined amount of propellant, but in doing so, the amount of pressurized air and mass of water needs to be accounted for, as well.

"This whole system is more or less based on the velocity of the projectile. The faster the projectile flies, the more pressurized air and water mass you need to try and slow it down," Marchak says.

Marchak says that in order to determine the amount of air pressure and water mass used in the system, many variables need to be considered, including the outside temperature, since the density of the pressurized air changes with temperature.

"We also have a lot of instrumentation, pressure gauges, accelerometers, temperature sensors, proximity sensors," Marchak says. "We are trying to measure and characterize how the projectile and the shockwave that comes off the projectile travel down the tube."

The data is dumped into an electronics data conex box alongside the catch system, then transferred to the safety bunker where a team of engineers save, process, and evaluate the information.

Some of the items tested in the SCat gun include electronic safe and arm devices, GPS electronics boards, infrared cameras, control actuation systems, guidance and navigation units, and many more mechanical and electrical components.

Current customers include the U.S. Army, Excalibur, Honeywell, Lockheed Martin, Rockwell Collins, BAE, and Goodrich.

The Goodrich use of the SCat Gun System has been increasing, with the team achieving a milestone of its 500th shot on May 22, 2012.

A typical test day includes four to five test shots at an average cost of $28,000, which Marchak describes as a small price for helping warfighters in the pursuit of battlefield dominance.

The first round fired from the 155-mm SCat Gun System came in April 2007. Now, with 559 shots completed to date, Marchak says the system is becoming the standard for precision munitions testing.

Published September 2012

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