Quadcopter propeller torque/thrust testing
The quadcopter's four propellers are designed to work in conjunction with each other to ensure that there are no torque imbalances that could send the vehicle spinning out of control. But just how would a professional developer or hobbyist perform accurate propeller torque and thrust testing? Advanced sensor specialist FUTEK has the answer.
Read the full article.
Engineer's Toolbox: How to choose the right relay
Relays come in a variety of form factors, styles, and technologies. Depending on your application, only one relay type may be suitable. In other cases, multiple relay types may be appropriate. By understanding the strengths and weaknesses of the different relays, you should be able to pick the one that is best suited for the job at hand. National Instruments lays out the options.
Read the full article.
Cool Tools: New Raspberry Pi 3 Model A+
Fans of the extremely popular credit card-sized computer called Raspberry Pi have something new to celebrate. The line of highly customizable base units has expanded with the third-gen A+ board, which brings the latest features and capabilities to a more compact form factor and lower price point -- only 25 bucks (and we have seen this on sale for under 20)!
Read the full article.
Vandal-resistant sealed switches
C&K has just launched its ATP19 and ATP22 series anti-vandal sealed pushbutton switches. The new high-strength, lightweight switches are IP67/IK10 rated, ensuring their suitability for operation in harsh conditions and ability to withstand potential malicious damage. The switches are also corrosion resistant and offer the industry-standard ring-illuminated version in 19-mm and 22-mm diameters.
New inductive-technology position sensors
Novotechnik's TF1 Series touchless linear position sensors overcome issues with legacy magnetostrictive technology. They are unaffected by strong magnetic fields and metal flakes or filings present in a user's environment. The TF1 Series consists of an inductively coupled position marker attached to a moving rod/piece of the user's application that requires a position measurement and the sensor with operational and programming status LEDs. While operating, LEDs indicate whether the sensor is operating and the marker within measuring range or out of range, as well as indicating results of internal diagnostics for valid output from the sensor. Can also measure speed and temperature.
Sensor development kit for power-optimized IoT applications
The RSL10 Sensor Development Kit from ON Semiconductor is designed to provide engineering teams with a comprehensive platform for developing IoT applications with cutting-edge smart sensor technology, enabled by the industry's lowest power Bluetooth Low Energy radio. The kit brings together the highly integrated RSL10 System-in-Package (RSL10 SIP) with a range of advanced low-power sensors from Bosch Sensortec. The development platform provides nine degrees of freedom (DoF) detection and environmental monitoring, including ambient light, volatile organic compounds (VOC), pressure, relative humidity, and temperature. An ultra-low noise digital microphone is also included, along with a user-programmable RGB LED, three programmable push-button switches, and 64 kb of EEPROM. Using the RSL10 Sense and Control mobile application, developers can connect to the RSL10 Sensor Development Kit to monitor sensors and to evaluate the kit's features. The app also supports multiple commercial cloud platforms for uploading sensor data.
EC fans offer spark-proof IP68-ATEX protection for harsh AC applications
Orion Fans has expanded its family of Electronically Commutated (EC) fans to include spark-proof IP68-ATEX-rated versions for applications involving explosive atmospheres or flammable gases. Implementing IP68-ATEX fans into a design decreases the possibility of an explosion or fire. Available in a range of sizes including 60 mm, 120 mm, and 172 mm, the EC IP68-ATEX fans are ideal for a broad range of applications including appliances, commercial and process control, refrigeration, HVAC, electronic enclosures, and cabinets. By maintaining the same interface between the fan and equipment, EC fans can be used as drop-in replacements for equivalent-sized AC fans. The AC input fans utilize a brushless DC motor and incorporate voltage transformation within the motor for significantly lower power consumption. This equates to power savings of up to 50 percent.
Cable assemblies for demanding microwave and RF applications
Intelliconnect has expanded its cable assembly offering for high-frequency and mission-critical applications. Comprised of high-quality cables, connectors, and terminations, the highly reliable RF cable assembly product offering now includes Low Loss, Semi-Rigid, Semi-Flex, and Conformable versions. The microwave and RF cable assembly line is designed for a wide range of applications including marine, medical, mil/aero, microwave communications, oil and gas, rail traction, test and measurement, and more. Available in a variety of sizes and performance specs, these assemblies operate up to 70 GHz and beyond and can be armored internally or externally. Phase matching is also available. Assemblies can be specified as matched sets or built to a specified phase length.
How electronic flow sensors help spread road salt
Salt spreading trucks use a pre-wetting system when ice needs to be removed from roads and the temperatures are too low for direct salt spreading to work. The system sprays salt water onto the road salt as it is being spread to "jump start" the melting process. But how do you monitor the amount of pre-wet salt used?
Read this short, informative blog from Gems Sensors & Controls.
Bend the rules of lighting design: Cut and form LED sheets
VCC is bending the rules of lighting design with its new VentoFlex tiles. The VentoFlex modular lighting system opens up countless ways for architects and lighting designers to make an impact. Available in 12-in. x 12-in. sheets, these innovative LED tiles can be cut and formed around any design element, including rounded corners and tight spaces, without taking up much room at all -- just 0.15 in. (3.81 mm). A pair of scissors is the only tool required to cut VentoFlex tiles to the size and shape you desire. Ten or 15 tiles can be linked together to one driver and dimmer to create thousands of square inches of versatile lighting power!
Learn more about this new and exciting lighting technology.
Slip rings improve Ethernet transmission
The Kuebler Group offers contact and contactless slip rings for reliable Ethernet transmission, achieving higher data rates and greater cycle synchronicity in demanding industrial environments. Application examples include industrial automation, bottling plants, labeling machines, rotary tables, and other processes requiring high transmission rates. The standard Slip Ring SR120 features an innovative three-chamber system and shield to enable parallel, interference-free Ethernet transmission up to 100 Mbps. It boasts a long service life up to 500 million revolutions and a rugged, modular structure that can be expanded up to 20 channels. Another model, the Slip Ring SR160 with integrated Sendix Encoder, provides position information in addition to contactless Ethernet transmission -- either two channels at 100 Mbps multiplexed or one channel at 1 Gbps.
How to convert from hydraulic to electric high-force linear actuators
Machine designers are converting existing linear motion systems from hydraulic to electric due to the technology's many benefits, but the process involves considering the actual force output of the cylinder, the duty cycle, and the motion profile. Specialists at Tolomatic tackle these points. Includes a very informative video.
Read the Tolomatic blog.
Integrate Alexa and more into your product or project
The MATRIX Voice Development Kit from MATRIX Labs aims to lower the barriers to entry for the creation and deployment of Internet of Things (IoT) voice applications. This platform enables users to develop voice recognition and detection projects that utilize Google Assistant or Amazon Alexa -- or any other voice recognition API. This open-source platform for the Raspberry Pi consists of a 3.14-in.-diameter development board, a radial array of 7 MEMS microphones, a Xilinx Spartan6 FPGA with 64 Mbit SDRAM, 18 RGBW LEDs, and 64 GPIO pins. It can also be used as a standalone device with the ESP32. Available from Newark element14.
Learn more from MATRIX Labs.
See purchase options from Newark element14.
Cool Tools: New Raspberry Pi Compute Module 3+
Newark element14 is now shipping the new Raspberry Pi Compute Module 3+ for same-day dispatch. Raspberry Pi Compute Module 3+ delivers the enhanced thermal performance and ease of use of Raspberry Pi 3 Model B+ in a smaller form factor, with a choice of memory variants suitable for a broad range of embedded applications including IoT devices and industrial automation, monitoring, and control systems. Compute Module 3+ simplifies the design process engineers need to undertake when developing a System on Module (SoM) solution into their final product. Engineers do not need to concern themselves with the complexities of interfacing with the BCM2837B0 processer directly and instead can concentrate on designing the interfaces to their own IO board and their application software -- simplicity that fosters rapid development.
360-degree static eliminator is CE, UL, and RoHS certified
EXAIR's new Gen4 Super Ion Air Wipe provides a uniform 360-degree ionized airstream that clamps around a continuously moving part to eliminate static electricity and contaminants. It is ideal for removing dust, particulates, and personnel shocks on pipe, cable, extruded shapes, hose, wire, and more. This engineered product has undergone independent lab tests to certify it meets the rigorous safety, health, and environmental standards to attain the CE and UL marks. It is also RoHS compliant. New design features include a metal armored high-voltage cable to protect against abrasion and cuts, a replaceable emitter point, integrated ground connection, and electromagnetic shielding.
MIT, IBM, and other collaborators show off new power conversion device that significantly cuts energy waste
A new design could decrease inefficiencies in electric vehicles, data centers, and the power grid dramatically.
By Larry Hardesty, MIT
Power electronics, which do things like modify voltages or convert between direct and alternating current, are everywhere. They're in the power bricks we use to charge our portable devices; they're in the battery packs of electric cars; and they're in the power grid itself, where they mediate between high-voltage transmission lines and the lower voltages of household electrical sockets.
Power conversion is intrinsically inefficient: A power converter will never output quite as much power as it takes in. But recently, power converters made from gallium nitride have begun to reach the market, boasting higher efficiencies and smaller sizes than conventional, silicon-based power converters.
Commercial gallium nitride power devices can't handle voltages above about 600 V, however, which limits their use to household electronics.
MIT postdoc Yuhao Zhang handles a wafer with hundreds of vertical gallium nitride power devices fabricated from the Microsystems Technology Laboratories production line. [Courtesy of Yuhao Zhang]
At the recent Institute of Electrical and Electronics Engineers' International Electron Devices Meeting (Dec. 4-6, 2017), researchers from MIT, semiconductor company IQE, Columbia University, IBM, and the Singapore-MIT Alliance for Research and Technology, presented a new design that, in tests, enabled gallium nitride power devices to handle voltages of 1,200 V.
That's already enough capacity for use in electric vehicles, but the researchers emphasize that their device is a first prototype manufactured in an academic lab. They believe that further work can boost its capacity to the 3,300-V to 5,000-V range, to bring the efficiencies of gallium nitride to the power electronics in the electrical grid itself.
That's because the new device uses a fundamentally different design from existing gallium nitride power electronics.
"All the devices that are commercially available are what are called lateral devices," says Tomás Palacios, who is an MIT professor of electrical engineering and computer science, a member of the Microsystems Technology Laboratories, and senior author on the new paper. "So the entire device is fabricated on the top surface of the gallium nitride wafer, which is good for low-power applications like the laptop charger. But for medium- and high-power applications, vertical devices are much better. These are devices where the current, instead of flowing through the surface of the semiconductor, flows through the wafer, across the semiconductor. Vertical devices are much better in terms of how much voltage they can manage and how much current they control."
For one thing, Palacios explains, current flows into one surface of a vertical device and out the other. That means that there's simply more space in which to attach input and output wires, which enables higher current loads.
For another, Palacios says, "when you have lateral devices, all the current flows through a very narrow slab of material close to the surface. We are talking about a slab of material that could be just 50 nanometers in thickness. So all the current goes through there, and all the heat is being generated in that very narrow region, so it gets really, really, really hot. In a vertical device, the current flows through the entire wafer, so the heat dissipation is much more uniform."
Narrowing the field
Although their advantages are well-known, vertical devices have been difficult to fabricate in gallium nitride. Power electronics depend on transistors, devices in which a charge applied to a "gate" switches a semiconductor material -- such as silicon or gallium nitride -- between a conductive and a nonconductive state.
For that switching to be efficient, the current flowing through the semiconductor needs to be confined to a relatively small area, where the gate's electric field can exert an influence on it. In the past, researchers had attempted to build vertical transistors by embedding physical barriers in the gallium nitride to direct current into a channel beneath the gate.
But the barriers are built from a temperamental material that's costly and difficult to produce, and integrating it with the surrounding gallium nitride in a way that doesn't disrupt the transistor's electronic properties has also proven challenging.
Palacios and his collaborators adopt a simple but effective alternative. The team includes first authors Yuhao Zhang, a postdoc in Palacios's lab, and Min Sun, who received his MIT PhD in the Department of Electrical Engineering and Computer Science (EECS) last spring; Daniel Piedra and Yuxuan Lin, MIT graduate students in EECS; Jie Hu, a postdoc in Palacios's group; Zhihong Liu of the Singapore-MIT Alliance for Research and Technology; Xiang Gao of IQE; and Columbia's Ken Shepard.
Rather than using an internal barrier to route current into a narrow region of a larger device, they simply use a narrower device. Their vertical gallium nitride transistors have bladelike protrusions on top, known as "fins." On both sides of each fin are electrical contacts that together act as a gate. Current enters the transistor through another contact, on top of the fin, and exits through the bottom of the device. The narrowness of the fin ensures that the gate electrode will be able to switch the transistor on and off.
"Instead of doing the complicated zigzag path for the current in conventional vertical transistors," Professor Tomás Palacios says, "let's change the geometry of the transistor completely." Their vertical gallium nitride transistors have bladelike protrusions on top, known as "fins." The narrowness of the fin ensures that the gate electrode will be able to switch the transistor on and off. [Courtesy of the researchers]
"Yuhao and Min's brilliant idea, I think, was to say, 'Instead of confining the current by having multiple materials in the same wafer, let's confine it geometrically by removing the material from those regions where we don't want the current to flow,'" Palacios says. "Instead of doing the complicated zigzag path for the current in conventional vertical transistors, let's change the geometry of the transistor completely."
Published December 2017
Rate this article