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LED luminaires require precise power and heat management because LEDs convert most of the electrical energy they receive into heat rather than light. Without adequate thermal management, this heat can degrade the LED's life span and affect color output. Also, LEDs can fail short because they are silicon devices, so they may require fail-safe backup in the form of overcurrent protection. Resettable PPTC (polymeric-positive-temperature-coefficient) circuit-protection devices have demonstrated their effectiveness in a variety of LED-lighting applications. Like traditional fuses, they limit current after they exceed specified limits. However, unlike fuses, PPTC devices can reset after the fault clears and the power cycles.

ZMD AG has launched the second wave of the company's ZLED family of LED control solutions with two new low-voltage ICs designed for battery-powered handheld devices. The ZLED7012 and ZLED7022 incorporate low-noise, constant-frequency charge pump DC/DC converters that can efficiently drive up to four (ZLED7012) or six (ZLED7022) strings of LEDs.

The MiniZeni series from Sharp radiates high efficiency, deliver high color rendering index (CRI) values of up to 87 and boast a long service life whilst measuring only 15x12x1.6mm. The six new models of the MiniZeni series are characterised by four special features: they have compact outer dimensions and are extremely flat, economical and bright.

By now most residents of the Dallas / Fort Worth area are aware of the giant, 35,000 lbs steel robot that towers over DART's Deep Ellum rail station. Robot builders may also be aware of the robot from coverage in Robot Magazine. Now, the rest of the world is taking notice because the prominent art organization, Americans for the Arts, has included the Dallas Robot, known officially as Traveling Man, on its list of 40 Best Public Art Works in the US and Canada. Read on to learn more about Traveling Man and see more photos of the big robot and little chrome friends.So what's the story behind this giant robot? A combination of opportunities and influences led to its creation. Dallas Area Rapid Transit or DART as it's known locally, was expanding into the Deep Ellum area with a new rail line and a Deep Ellum rail station. Deep Ellum is the historic Dallas arts district from which have come a long list of musical and visual artists. The area is also well known for its many public art pieces, many improvised in local do-it-yourself fashion. Painters and sculpters often create art on the exterior of their own or other buildings in the area.

Researchers at Purdue University have developed a new design employing carbon nanotubes and small copper spheres that wicks water passively towards hot electronics that could meet the challenges brought on by increasing frequency speeds in chips. The problem of overheating electronics is well-documented and in the past the issue has been addressed with bigger and bigger fans. But with chip features shrinking below 50 nanometers the fan solution is just not cutting it. The Purdue researchers, led by Suresh V. Garimella, came up with a design that uses water as the coolant liquid and transfers the water to an ultrathin thermal ground plane. The design naturally pushes the water through obviating the need for a pump and through the use of microfluidic design is able to boil the water fully, which allows the wicking away of more heat.

Japanese robotics company HiBot has unveiled a nimble snake bot capable of moving inside air ducts and other narrow places where people can't, or don't want to, go. The ACM-R4H robot, designed for remote inspection and surveillance in confined environments, uses small wheels to move but it can slither and undulate and even raise its head like a cobra. The new robot, which is half a meter long and weighs in at 4.5 kilograms, carries a camera and LEDs on its head for image acquisition and can be fitted with other end-effectors such as mechanical grippers or thermo/infrared vision systems. Despite its seemingly complex motion capabilities, "the control of the robot is quite simple and doesn't require too much training," says robotics engineer and HiBot cofounder Michele Guarnieri.

Events such as natural disasters, military actions, and public safety threats have led to an increased need for robust robots — especially ones that can travel across complex terrain in any dimension. The ability to scale vertical building surfaces or other structures offers unique capabilities in military applications such as urban reconnaissance, sensor deployment, and setting up urban network nodes. SRI's novel clamping technology, called compliant electroadhesion, has enabled the first application of this technology to wall-climbing robots that can help with these situations.  As the name implies, electroadhesion is an electrically controllable adhesion technology. It involves inducing electrostatic charges on a wall substrate using a power supply connected to compliant pads situated on the moving robot. SRI has demonstrated robust clamping to common building materials including glass, wood, metal, concrete, etc. with clamping pressures in the range of 0.5 to 1.5 N per square cm of clamp (0.8 to 2.3 pounds per square inch). The technology works on conductive and non-conductive substrates, smooth or rough materials, and through dust and debris. Unlike conventional adhesives or dry adhesives, the electroadhesion can be modulated or turned off for mobility or cleaning. The technology uses a very small amount of power (on the order of 20 microwatts/Newton weight held) and shows the ability to repeatably clamp to wall substrates that are heavily covered in dust or other debris.

Ever since graphene was first produced in a lab at the University of Manchester in 2004, researchers around the world have been fascinated with its potential in electronics applications. Graphene possessed all the benefits of carbon nanotubes (CNTs), namely its charged-carrier mobility, but it didn’t have any of the down sides, such as CNTs’ need for different processing techniques than silicon and the intrinsic difficulty of creating interconnects for CNTs. But all was not easy for applying graphene to electronics applications. One of the fundamental problems for graphene was its lack of a band gap, which left it with a very low on-off ratio measured at about 10 as compared to in the 100s for silicon. Now this fundamental hurdle has been overcome. Based on research led by Phaedon Avouris at IBM’s IBM T.J. Watson Research Center, Yorktown Heights, New York, IBM is reporting that they have created a significant band gap in graphene.

The consumer handheld market is growing by leaps and bounds. With more processing power and increased support for more applications, portable products are cross-pollinating with traditional computing systems even as the product life cycle has decreased considerably in this market segment. As a result, especially in this era of economic slowdown, it is imperative that new products meet the time-to-market window to gain maximum acceptance. A decrease in product life cycles requires a reduced development cycle and an increased emphasis on reusability and reprogrammability. The emerging handheld market is also seeing interesting trends in which each individual device in a family has lower volumes but there is more customization across the series of devices, effectively upping the total unit volumes. The key challenge then becomes how to develop a system that is widely reusable and also customizable. These requirements have led designers increasingly to turn to the FPGA for handheld-product development. The FPGA has become more powerful and feature-rich, while gate counts, area and frequency have increased. FPGA development and turnaround cycles are considerably shorter than those of custom ASICs, and the added advantage of reprogrammability can make the FPGA a more compelling solution for handheld embedded systems.

In what comes as a bit of a surprise, Fuji Soft Inc.’s new humanoid robot platform for hobbyists and researchers has been given the name PALRO (pal + robot).  Naturally we feel this name is a superb choice!  Sales to research institutions will begin on March 15th, 2010 with a general release following later in the year.  The robot combines Fuji Soft’s software prowess with an open architecture which will give developers plenty of room to experiment. PALRO stands 39.8cm (15″) tall and weighs 1.9kg (3.5 lbs), and here’s the good news: it costs 298,000 JPY ($3300 USD).  Considering PALRO has 20 DOF, a camera, 4 directional microphones, a speaker, LED arrays in its head and chest, 4 pressure sensors in each foot, 3-axis gyro sensor, an accelerometer, and an Intel Atom 1.6GHz CPU, it is priced very competitively.  A comparative robot kit like Vstone’s Robovie-PC for example, costs $1100 USD more and doesn’t have such a fancy exoskeleton.

Although any T. Rex–enthralled kid will tell you that a gigantic asteroid wiped the dinosaurs off the planet, scientists have always regarded this impact theory as a hypothesis subject to revision based on further evidence gathered from around the globe. Other possible causes, such as volcanism and smaller, multiple asteroid strikes, never actually went away, and over the years researchers raised important points that did not fully jibe with a history-changing celestial impact near the Yucatan peninsula one awful day some 65.5 million years ago. A group of 41 researchers have pored over the evidence and decided that—in accordance with the original postulate put forth 30 years ago by a team led by father and son researchers Luis and Walter Alvarez—it was, indeed, a massive asteroid that slammed into Earth, creating Chicxulub Crater on Mexico's Gulf Coast, that killed off many of the species on the planet, including the non-avian dinosaurs.

Researchers at the NanoRobotics Laboratory of the École Polytechnique de Montréal, in Canada, are putting swarms of bacteria to work, using them to perform micro-manipulations and even propel microrobots. Led by Professor Sylvain Martel, the researchers want to use flagellated bacteria to carry drugs into tumors, act as sensing agents for detecting pathogens, and operate micro-factories that could perform pharmacological and genetic tests. They also want to use the bacteria as micro-workers for building things. Things like a tiny step pyramid. The video below shows some 5000 bacteria moving like a swarm of little fish, working together to transport tiny epoxy bricks and assemble a pyramidal structure -- all in 15 minutes. The video was presented at IROS last year, along with a wonderfully titled paper, "A Robotic Micro-Assembly Process Inspired By the Construction of the Ancient Pyramids and Relying on Several Thousands of Flagellated Bacteria Acting as Workers."

Walking, swallowing, respiration and many other key functions in humans and other animals are controlled by Central Pattern Generators (CPGs). In essence, CPGs are small, autonomous neural networks that produce rhythmic outputs, usually found in animal's spinal cords rather than their brains. Their relative simplicity and obvious success in biological systems has led to some success in using CPGs in robotics. However, current systems are restricted to very simple CPGs (e.g., restricted to a single walking gait). A recent breakthrough at the BCCN at the University of Göttingen, Germany has now allowed to achieve 11 basic behavioral patterns (various gaits, orienting, taxis, self-protection) from a single CPG, closing in on the 10–20 different basic behavioral patterns found in a typical cockroach. The trick: Work with a chaotic, rather than a stable periodic CPG regime. For more on CPGs, listen to the latest episode of the Robots podcast on Chaos Control, which interviews Poramate Manoonpong, one of the lead researchers in Göttingen, and Alex Pitti from the University of Tokyo who uses chaos controllers that can synchronize to the dynamics of the body they are controlling.

Carved in stone on a Civil War-era bridge -- a world-class feat of engineering that stands a couple miles northwest of Washington -- are the names of builders and officials of the day.

A key name, however, is missing. New research shows that Virginian Alfred R. Rives led the design and construction of the Cabin John Bridge. Also called the Union Arch Bridge, the aqueduct and roadway reaches 220 feet across Cabin John Creek in a single span -- the world's longest single-span masonry bridge for nearly 40 years and the nation's longest still today.

The moving parts of micromechanical machines tend to seize up under the forces of sticking and friction that engineers call stiction. The problem yields to solid lubricants, notably graphite (sheets of carbon atoms called graphene stacked in layers), although for a long time no one understood exactly why this happens. Now nanotechnology researchers, led by Professor Robert Carpick at the University of Pennsylvania and Professor James Hone at Columbia University, in New York City, have shown that how effective the lubrication is depends on the number of layers of graphene in the graphite. In particular, more layers means better lubrication. Because the same relationship between layers and lubrication occurs in thin sheets of molybdenum disulfide, niobium diselenide, and boron nitride—materials of widely differing properties—the workers conclude that this behavior is a fundamental aspect of friction. They expect that the discovery will lead to better lubrication of tiny moving parts. The researchers published details of their experiments in a recent issue of Science.

Sony Corp. has developed a highly flexible OLED display that can be rolled around a pencil and continue to operate. The 4.1-inch diagonal isplay is 80-microns thick and offers 432 by 240 by RGB pixels resolution at 121 pixels per inch. It is an organic LED full color display driven by an organic thin-film transistor matrix.

Researchers at MIT's Object Based Media Group (OBMG), led by professor Michael Bove, have developed a 3D hologram using the Xbox Kinect and a laptop. Three GPUs on a graphic card are used to generate diffraction patterns that produce a Star-Wars-Style hologram at 15 frames per second. More information is available in a PopSci web article.

People have been using pens to jot down their thoughts for thousands of years but now engineers at the University of Illinois have developed a silver-inked rollerball pen that allows users to jot down electrical circuits and interconnects on paper, wood and other surfaces. Looking just like a regular ballpoint pen, the pen's ink consists of a solution of real silver that dries to leave electrically conductive silver pathways. These pathways maintain their conductivity through multiple bends and folds of the paper, enabling users to personally fabricate low-cost, flexible and disposable electronic devices. While metallic inks have been used to manufacture electronic devices using inkjet printing technology, the silver pen offers users the freedom and flexibility to construct electronic devices on the fly, says Jennifer Lewis, the Hans Thurnauer professor of materials science and engineering at the University of Illinois who led the research team along with Jennifer Bernhard, a professor of electrical and computer engineering.