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The I-35 Bridge: The truth is out there
Whenever engineers discuss the I-35 bridge collapse in Minneapolis, the overriding question is: "How could such a thing happen?" There are many theories, but most lead to the question: “Who was watching the store during repairs?” In past columns, I often refer to hazard analysis, a technique for proactively avoiding product failures and unsafe conditions. It should be used for all designs, including bridges. Prior to building this bridge, the design should have been analyzed for all reasonably foreseeable situations. This would include the expected life of the bridge. Was it? I do not know. This information is not readily available, but I hope it is included in the accident report when it finally comes out.
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Simultaneous 3-Axis X, Y and Z Beam Control
Revolutionizes Laser Marking
 The new KEYENCE MD-V9900 YVO4 Laser Marker features the world’s first, real-time, 3-axis beam control. The MD-V9900 provides distortion-free marking of products with different heights, inclined surfaces, cylinders or circular cones at production line speeds. This revolutionary performance is made possible by a 42mm variable focal length, a variable beam spot size and an ultra-large 300 x 300mm marking area. The MD-V9900 eliminates the need to move the marker or products to achieve perfect marking.
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 Machine Design Editor Leland Teschler: Are CFLs really a bright idea?
Compact fluorescent lamps were in the news recently when U.S. legislators passed a Bill that mandated energy-efficiency standards light bulbs must meet by 2014. The Bill would make it impossible to sell the incandescent bulbs we have today. Coincidentally, EC&M Magazine, a publication for electrical contractors, published letters to the editor expressing alarm that legislators are enacting laws favoring CFLs. “I am as much for greening the world as anyone,” said one letter writer, who then pointed out numerous problems with CFLs, before concluding that, “mandated stupidity is not the way to go.”
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Wind tunnel tests future space planes 
The X-51A aircraft carries engines called scramjets that can power the plane to target speeds close to Mach 6 or six times the speed of sound. The advanced aircraft is expected to evolve into missiles able to hit mobile and time-critical targets. The X-51A is wedge-shaped, with a scoop-like cowl on its underbelly, where air rushes into the inlet of the engine's combustor. It is critical that air entering the inlet be turbulent at hypersonic speeds or the engine could stop. Because of this, air must be converted to turbulent flow before entering the inlet. Engineers installed a raised strip of metal near the inlet to trip the air from smooth to turbulent.
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Design and Deploy your Machines Faster
The new National Instruments CompactRIO integrated systems are advanced programmable automation controllers (PACs) that combine an industrial real-time processor and a reconfigurable FPGA within a single chassis, lowering the cost of CompactRIO for high-volume machine control and monitoring applications. Engineers and machine builders can quickly program and customize the FPGA within the CompactRIO using NI LabVIEW 8.5 software.
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An uplifting experience 
The design of a lift for fragile 300-mm semiconductor wafers gets stiffness just right to synthesize smooth motion. When the semiconductor industry moved to 300-mm wafers a few years ago, it changed the whole manner of working within chip fabs. In earlier times, it was not uncommon to see cleanroom workers manually carrying racks of wafers from one processing station to another. Semiconductor makers basically used batch-fabrication methods. There was little automation when it came to moving inprocess wafers from one fabrication step to the next.
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