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Supersonic Laser-Propelled Rockets Could Help Aircraft Exceed Mach 10

A new method for improving the thrust generated by laser-propulsion systems may bring them one step closer to practical use. The method, developed by physicists Yuri Rezunkov of the Institute of Optoelectronic Instrument Engineering, Russia, and Alexander Schmidt of the Ioffe Physical Technical Institute in Saint Petersburg, Russia, integrates a laser‑ablation propulsion system with the gas‑blasting nozzles of a spacecraft. Combining the two systems can increase the speed of the gas flow out of the system to supersonic speeds, while reducing the amount of burned fuel.

Posted in: Photonics, Lasers & Laser Systems, Motion Control, Power Transmission, Aerospace, Aviation, News

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Moving Cameras Track Objects Automatically

University of Washington electrical engineers have developed a way to automatically track people across moving and still cameras by using an algorithm that trains the networked cameras to learn one another’s differences. The cameras first identify a person in a video frame, then follow that same person across multiple camera views.“Tracking humans automatically across cameras in a three-dimensional space is new,” said lead researcher Jenq-Neng Hwang, a UW professor of electrical engineering. “As the cameras talk to each other, we are able to describe the real world in a more dynamic sense.”Imagine a typical GPS display that maps the streets, buildings and signs in a neighborhood as your car moves forward, then add humans to the picture. With the new technology, a car with a mounted camera could take video of the scene, then identify and track humans and overlay them into the virtual 3-D map on your GPS screen. The UW researchers are developing this to work in real time, which could help pick out people crossing in busy intersections, or track a specific person who is dodging the police.“Our idea is to enable the dynamic visualization of the realistic situation of humans walking on the road and sidewalks, so eventually people can see the animated version of the real-time dynamics of city streets on a platform like Google Earth,” Hwang said.SourceAlso: Learn about Machine Vision for High-Precision Volume Measurement.

Posted in: Electronics & Computers, Cameras, Video, Visualization Software, Imaging, News

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Ocean Gliders Measure Melting Polar Ice

The rapidly melting ice sheets on the coast of West Antarctica are a potentially major contributor to rising ocean levels worldwide. Although warm water near the coast is thought to be the main factor causing the ice to melt, the process by which this water ends up near the cold continent is not well understood. Using robotic ocean gliders, Caltech researchers have now found that swirling ocean eddies, similar to atmospheric storms, play an important role in transporting these warm waters to the Antarctic coast—a discovery that will help the scientific community determine how rapidly the ice is melting and, as a result, how quickly ocean levels will rise. "When you have a melting slab of ice, it can either melt from above because the atmosphere is getting warmer or it can melt from below because the ocean is warm," explains lead author Andrew Thompson, assistant professor of environmental science and engineering. "All of our evidence points to ocean warming as the most important factor affecting these ice shelves, so we wanted to understand the physics of how the heat gets there." Because the gliders are small—only about six feet long—and are very energy efficient, they can sample the ocean for much longer periods than large ships can. When the glider surfaces every few hours, it "calls" the researchers via a mobile phone–like device located on the tail. The communication allows the researchers to almost immediately access the information the glider has collected. Like airborne gliders, the bullet-shaped ocean gliders have no propeller; instead they use batteries to power a pump that changes the glider's buoyancy. When the pump pushes fluid into a compartment inside the glider, the glider becomes denser than seawater and less buoyant, thus causing it to sink. If the fluid is pumped instead into a bladder on the outside of the glider, the glider becomes less dense than seawater—and therefore more buoyant—ultimately rising to the surface. Like airborne gliders, wings convert this vertical lift into horizontal motion. Source Also: Learn about Remote Sensing of Ice Sheets and Snow.

Posted in: Batteries, Electronics & Computers, Environmental Monitoring, Green Design & Manufacturing, Motion Control, Test & Measurement, Measuring Instruments, Monitoring, Communications, Machinery & Automation, Robotics, News

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Microbot Muscles Self-Assemble and Flex

In a step toward robots smaller than a grain of sand, University of Michigan researchers have shown how chains of self-assembling particles could serve as electrically activated muscles in the tiny machines."We are inspired by ideas of microscopic robots," said Michael Solomon, a professor of chemical engineering. "They could work together and go places that have never been possible before."Solomon and his group demonstrated that some gold plating and an alternating electric field can help oblong particles form chains that extend by roughly 36 percent when the electric field is on.The team started with particles similar to those found in paint, with diameters of about a hundredth the width of a strand of hair. They stretched these particles into football shapes and coated one side of each football with gold. The gilded halves attracted one another in slightly salty water—ideally about half the salt concentration in the sports drink Powerade. The more salt in the water, the stronger the attraction.Left to their own devices, the particles formed short chains of overlapping pairs, averaging around 50 or 60 particles to a chain. When exposed to an alternating electric field, the chains seemed to add new particles indefinitely. But the real excitement was in the way that the chains stretched."We want them to work like little muscles," said Sharon Glotzer, the Stuart W. Churchill Professor of Chemical Engineering. "You could imagine many of these fibers lining up with the field and producing locomotion by expanding and contracting."SourceAlso: Learn about Microelectronic Repair Techniques for Wafer-Level Integration.

Posted in: Electronics & Computers, Materials, Machinery & Automation, Robotics, News

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NASA Technologists Advance Next-Generation 3D Imaging

Building, fixing, and refueling space-based assets or rendezvousing with a comet or asteroid will require a robotic vehicle and a super-precise, high-resolution 3D imaging lidar that generates the real-time images needed to guide the vehicle to a target traveling at thousands of miles per hour.A team of technologists at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, is developing a next-generation 3D scanning lidar — dubbed the Goddard Reconfigurable Solid-state Scanning Lidar (GRSSLi) — that could provide the imagery required to execute these orbital dances.Equipped with a low-power, eye-safe laser, a micro-electro-mechanical scanner, and a single photodetector, GRSSLi will "paint" a scene with the scanning laser. Its detector will sense the reflected light to create a high-resolution 3-D image at kilometer distances — a significant increase in capability over current imaging lidars that are effective only at meter distances.Just as important, the instrument is equipped with onboard "vision" algorithms that interpret the three-dimensional image returned by the lidar. The softwar estimates location and attitude of a target relative to the lidar.SourceAlso: Learn about NASA's Asteroid Redirect Mission.

Posted in: Visualization Software, Imaging, Photonics, Lasers & Laser Systems, Aerospace, RF & Microwave Electronics, News

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Cockroach Biobots Detect Sound

North Carolina State University researchers have developed technology that allows cyborg cockroaches, or biobots, to pick up sounds with small microphones and seek out the source of the sound. The technology is designed to help emergency personnel find and rescue survivors in the aftermath of a disaster.The researchers have also developed technology that can be used as an “invisible fence” to keep the biobots in the disaster area.“In a collapsed building, sound is the best way to find survivors,” says Dr. Alper Bozkurt, an assistant professor of electrical and computer engineering at NC State and senior author of two papers on the work.The biobots are equipped with electronic backpacks that control the cockroach’s movements. Bozkurt’s research team has created two types of customized backpacks using microphones. One type of biobot has a single microphone that can capture relatively high-resolution sound from any direction to be wirelessly transmitted to first responders.The second type of biobot is equipped with an array of three directional microphones to detect the direction of the sound. The research team has also developed algorithms that analyze the sound from the microphone array to localize the source of the sound and steer the biobot in that direction. SourceAlso: Learn about FINDER (Finding Individuals for Disaster and Emergency Response).

Posted in: Electronics & Computers, Communications, Wireless, Machinery & Automation, Robotics, News

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Light Bending Material Facilitates Search for New Particles

Particle physicists have a hard time identifying all the elementary particles created in their particle accelerators. But now researchers at Chalmers University of Technology have designed a material that makes it much easier to distinguish the particles.

Posted in: Photonics, Optics, Materials, Solar Power, Energy, News

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