Rapid proliferation of wireless devices for both industrial and personal use is spurring demand for an educated workforce that understands this quickly developing technology. Universities across the country are adding coursework in this area, but not all have hands-on labs to support textbook learning. One exception is the University of South Florida (USF) in Sarasota. With ESG Signal Generators and Vector Signal Analyzer software donated by Agilent Technologies Inc., Santa Clara, Calif., along with support from the National Science Foundation, USF's electrical engineering department has built a state-of-the-art Wireless Communications and Signal Processing Lab (WCSL).
The lab's goal is to develop competent students who are well educated in multiple areas of wireless communications. The lab features three benches with two stations each, allowing the engineering department to put 18 students through the program per semester, typically 70% graduate and 30% undergraduate students.
The equipment enables students to capture signals over the air and then use test instrumentation to digitize and process them. Students then analyze the signals with software, including Agilent's SystemVue and ADS, and MathWorks' MATLAB. They also learn how to analyze RF components, such as mixers, amplifiers, oscillators, and filters, as well as evaluate wireless channels, working with RF, IF, or baseband, controlling the test equipment at every stage. Signal analysis can be achieved down to the bit level. The lab also provides students with access to anechoic and reverberation chambers as well as indoor multi-path channels, which gives them the opportunity to measure multi-path fading and interference using constellation, eye diagram, and error-vector-magnitude measurement techniques.
“Wireless communications concepts are becoming more and more difficult, so we really need something that can bridge concepts to reality, and the Agilent equipment helps accomplish this. This lab makes my job easier,” says Dr. Huseyin Arslan, associate professor.
Testing system spots assembly errors
Consider the challenge of confirming that every last screw on an aircraft's fuselage is properly installed. Now a new testing system can verify such assemblies, even for small production runs.
Everything from aircraft to cars is increasingly customized to end-user specifications, which complicates manufacturing and often precludes automated assembly. In cases where manufacturers must rely on manual labor, employees use either design drawings to confirm proper attachment of individual parts, or inflexible testing systems that check parts against comparison photos. Testing calls for identical part and template photo matches, but this is difficult for one-off designs. Now, researchers at the Fraunhofer Institute for Factory Operation and Automation IFF, Magdeburg, Germany, have developed testing technology suitable even for single-part production runs.
“The automated visual testing system generates a digital template and uses it to compare with the assembled components — and reliably identifies errors,” says Steffen Sauer, project manager for measuring and testing technology at IFF.
First, an automated camera system takes hundreds of photos of individually assembled holders, load-bearing elements, and parts while logging exact camera position. At the same time, software regenerates the shots using information from the design's original digital model. Next, the software compares the real and virtual images, and issues warnings for deviations. Improperly installed parts are highlighted on a monitor display.
In addition, the system checks already-completed assemblies in 3D by comparing design data with real assembly measurements. Here, conventional 3D measurement methods digitalize components, but the system automatically identifies the best measuring positions for every part to be tested. Then it forwards these to the camera-carrying robot, which in turn travels to the commanded positions, and shoots 2D or 3D images.
The testing program's most innovative features are its programming of a virtual camera that uses design models to “photograph” nonexistent assemblies, and software that automatically locates key areas, such as bracket and holder fittings, among millions of points in the 3D images to verify proper fittings. For more information, visit fraunhofer.de/en.html.
Concentrating solar design melts holes in coins
Soon, sunlight may be put to work in high-heat industrial applications. One such large-scale concentrating solar design bundles solar radiation to produce heat, much like a giant magnifying glass used to burn leaves. The Institute of Solar Research at the German Aerospace Center (DLR) in Cologne-Porz has developed the concentrating solar design that could soon generate electricity, heat, and fuel.
The prototype incorporates a 1.5-m-diameter parabolic mirror that can concentrate the sun's rays enough to melt metal — a 10,000-fold concentration of sunlight, with corresponding temperatures exceeding 3,000° C. In short, the Diskus solar dish (with short focal length for solar concentration) includes a parabolic mirror that tracks the sun in two axes. The highly concentrated solar radiation at the focal point — roughly 1 kW of light power with variable flux density — is available for different experiments and measurements. Energy flux densities of 10 MW/m2 can be achieved, though this requires the Diskus system to continually align the mirror with the sun.
At the heart of this function is a CX5020 Embedded PC from Beckhoff Automation, Burnsville, Minn., which handles all control functions. The position of the sun is calculated by the software function block FB_SPA in the TwinCAT Solar Position Algorithm library and is transferred to TwinCAT NC PTP to control two stepper motors. With a motor current to 5 A, the EL7041 stepper motor terminals for the EtherCAT Terminal system enable sufficiently high dynamics for the selected drive solution. Axis positions are fed back by two absolute rotary encoders mounted on the Diskus gearbox output, while the encoders are directly connected to an EL5002 SSI interface EtherCAT Terminal. Numerous EtherCAT Terminals are available for data acquisition and can evaluate a large number of signals.
Tracking accuracy was demonstrated at Aerospace Day at the DLR, held in September 2011. A container of coins mounted at the Diskus focal point allowed visitors to melt holes in coins whenever a break in the clouds permitted sunlight through. The speed with which this occurred demonstrated the sun's energy in a dramatic fashion. For more information, visit dlr.de/sf/en and beckhoff.com.
FIRST championship sets record attendance
The annual FIRST (For Inspiration and Recognition of Science and Technology) Championship, held in St. Louis at the end of April, achieved its biggest turnout in the event's history. More than 30,000 participants, fans, families, educators, and industry leaders celebrated students' engineering and robotics prowess. The International Society of Automation and the Automation Federation joined the event to talk with kids and parents about career options, while numerous industrial suppliers donated components to the contest's robot kits.
This year's Robotics Competition challenge, Rebound Rumble, involved basketball matches between two alliances of three teams each: Each alliance competed by robotically placing as many basketballs into hoops as possible during a two-minute match. Three teams from Stuart, Fla., Mountain Home, Ark., and North Brunswick, N.J., won the final showdown.
A not-for-profit organization founded in 1989 by inventor Dean Kamen, FIRST aims to inspire interest in science and technology. More than 600 teams from 32 countries competed in the FIRST LEGO League, Tech Challenge, and Robotics Competition. For more information, visit usfirst.org.
Trapped key interlock supplier
Tapeswitch Corp., Farmingdale, N.Y., supplies U.S. markets with trapped-key interlocks for power isolation and access safety. The components ensure electrical safety on many equipment types in myriad industries. Trapped-key machine guarding is a proven electromechanical technology that ensures safety procedures are followed when personnel physically accesses machinery — by forcing a predetermined sequence of safety protocols. The components are particularly suitable where energy sources must be isolated prior to gaining access to equipment. For more information, visit tapeswitch.com.
Rollon to roll out actuator line at IMTS
Rollon USA, Hackettstown, N.J., will enter the actuator marketplace and launch a complete line of products at IMTS, taking place September 10 to 15 in Chicago. The company's new Actuatorline, available in belt and screw-driven models, complements existing linear guide offerings, enabling complete motion systems that are designed and sized to work together. The new actuators are suited to a variety of OEM machinery applications, including robotic handling, conveyor systems and packaging machines, semiconductor equipment, X-Y-Z Cartesian robots, lab automation and life sciences platforms, machine tools and accessories, and part transfer and assembly lines. For more information, visit rollonnews.com.
Lenze opens Chicago facility
Lenze Americas, Uxbridge, Mass., announces the opening of an assembly and logistics facility in Glendale Heights, Ill. The 100,000 sq. ft. facility supports the manufacture of electromechanical components, including gearboxes, motors, and geared motors used in the automotive, packaging, material handling and logistics, robotics, and commercial equipment industries. The renovated building also includes a $1.2 million automated paint assembly line. For more information, visit lenzeamericas.com.