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Raytheon has successfully fired its new Excalibur N5 projectile during a recent live guided flight test at Yuma Proving Ground, Ariz.  It was fired from a 5-inch naval gun during testing (shown, top photo). Excalibur N5 (bottom photo) is a 5-inch/127 mm naval variant of the projectile used by the U.S. Army, the U.S. Marine Corps and several international armies--Sweden, Canada, Australia and the Netherlands have selected Excalibur for their military services. The projectile uses a built-in ruggedized GPS receiver and satellite signals to help guide itself to its intended target. It is expected to more than triple the maximum effective range of conventional naval gun munitions and deliver the same accuracy of the Excalibur Ib, which is in production today.


Excalibur’s  advantages include a major reduction in the time, cost and logistical burden associated with using conventional artillery munitions. It is being developed to support several critical naval mission areas including Naval Surface Fire Support, Anti-Surface Warfare (ASuW) and countering Fast Attack Craft (FAC). It is said to have what is known as “a radial miss distance” of less than two meters from the target, greatly reducing the possibility of collateral damage; the munition has been employed within 75 meters of supported troops. Nearly 770 Excalibur rounds have been fired in combat, according to its manufacturer.


The main challenge to GPS guided munitions comes from GPS jammers and spoofing equipment. This is not a theoretical threat: in 2011, North Korea blocked South Korean GPS signals, reportedly using Russian-made jamming equipment capable of disrupting the guided weapons. Also in 2011 Iran downed and captured an RQ-170 Sentinel drone, claiming it had spoofed GPS data and redirected the drone to land inside Iranian borders. In response to this counter-measure Raytheon is developing a laser-guided version of the projectile, to be called the Excalibur S. This variant incorporates a digital semi-active laser seeker, allowing it to hit moving targets and engage and strike targets without GPS-based location information. In this way it reduces the risk associated with GPS jamming.


Testing is continuing at Raytheon.


Silicon transistors have been made smaller year after year, but they are approaching a point of physical limitation. Continuing to shrink the size of the transistor – including the channels and contacts – without compromising performance has become a major technology hurdle..


Researchers have known that carbon nanotube (CNT) chips could provide an answer, greatly improving the capabilities of high performance computers and other devices, The carbon nanotubes form the core of a transistor device whose superior electrical properties promise several generations of technology scaling beyond the physical limits of silicon. The promise of CNTs centers on the fact that electrons in carbon transistors can move more easily than in silicon-based devices, and the ultra-thin body of carbon nanotubes provide additional advantages at the atomic scale


The trouble is as devices become smaller, increased contact resistance for carbon nanotubes has hindered performance gains. Inside a chip, the contacts are the valves that control the flow of electrons from metal into the channels of a semiconductor. As transistors shrink in size, electrical resistance increases within the contacts, which impedes performance


But now IBM researchers say they have found a way to forego traditional contact schemes and have invented a metallurgical process akin to microscopic welding that chemically binds the metal atoms to the carbon atoms at the ends of nanotubes. This ‘end-bonded contact scheme’ is said to allow the contacts to be shrunken down to below 10 nanometers without deteriorating performance of the carbon nanotube devices.


IBM, which had previously shown that carbon nanotube transistors can operate as excellent switches at channel dimensions of less than ten nanometers, says that the new development can overcome contact resistance challenges all the way to the 1.8 nanometer node – four technology generations away, Dario Gil, IBM vice president of Science and Technology characterized the breakthrough as bringing us “a step closer to the goal of a carbon nanotube technology within the decade.”.


Dark, narrow streaks on Martian slopes such as these at Hale Crater are believed to be formed by seasonal flow of water.  The streaks are roughly the length of a football field. Photo courtesy of: NASA/JPL-Caltech/Univ. of Arizona.

Scientists reported this morning that there is compelling evidence that liquid water exists on the surface of present-day Mars. The announcement was made based on new findings from NASA’s Mars Reconnaissance Orbiter (MRO) .Using an imaging spectrometer on MRO, researchers detected signatures of hydrated minerals on slopes where streaks are seen on the planet. These darkish streaks appear to ebb and flow over time, darkening and appearing to flow down steep slopes during warm seasons, and then fading in cooler seasons. They appear in several locations on Mars when temperatures are above minus 10 degrees Fahrenheit (minus 23 Celsius), and disappear at colder times.

In a paper published in the journal Nature Geoscience, Dr.Alfred S. McEwen, a professor of planetary geology at the University of Arizona and the principal investigator of images from a high-resolution camera on NASA’s MRO, and his colleagues identified salts of a type known as perchlorates in readings from orbit. The new findings of hydrated salts on the slopes point to what that relationship may be to these dark features. The hydrated salts would lower the freezing point of a liquid brine, just as salt on roads here on Earth causes ice and snow to melt more rapidly. Some perchlorates have been shown to keep liquids from freezing even when conditions are as cold as minus 94 degrees Fahrenheit (minus 70 Celsius).

NASA’s approach to searching for life in the universe has been to "follow the water". In the past when water on Mars has been discussed it was usually in the context of ancient water or frozen water. Today’s announcement shows there is more to the story as some sort of briny water appears to be flowing on the surface of the Red Planet.



If you wait around long enough sometimes reality gets closer to science fiction. In the 1982 film “Firefox” Clint Eastwood plays an American pilot assigned to steal a highly advanced Soviet fighter aircraft which, among other things, uses a helmet that allows the pilot to control weapons launch through thought. Recently, Rockwell Collins introduced the Gen III Helmet Mounted Display System (HMDS) for the F-35 aircraft that allows pilots in aircraft equipped with the system to simply look at a target within the 360 degree heads up display helmet to aim and fire their weapons. The pilot also receives target verification when receiving steering cues from onboard sensors or via datalink.

The helmet allows pilots to maintain spatial orientation of their surroundings and continually monitor critical flight information. For night missions, the HMDS projects the night vision scene directly onto the visor, eliminating the need for separate night vision goggles. All the information that pilots need to complete their missions through all weather, day or night is projected on the helmet’s visor, including sensor video. Additionally, the F-35’s Distributed Aperture System (DAS), made by Northrop Grumman, streams real-time imagery from six infrared cameras mounted around the aircraft to the helmet, allowing pilots to “look through” the airframe.

The HMDS serves as the virtual head-up display, enabling the F-35 to become the first tactical fighter in 50 years without a traditional head-up display. The helmet provides a 360-degree field-of-view and the pilot’s vantage point entirely remains outside of the aircraft; if the pilot were to tilt his head downward, for example, he’d have a view of the earth rather than a view of his legs.

Each helmet weighs approximately five pounds and is custom built and adjusted for each pilot during a two-day process so as to account for variables such as horizontal and vertical alignment of the pupils and eye spacing, to eliminate the possibility of motion sickness that sometimes comes along with 3D virtual reality headsets. The Gen III helmet will be introduced to the fleet in 2016.


C-130 Hercules carrying a tactical laser

When three top Air Force officers speaking separately at the same conference all say they expect the service to demonstrate airborne laser weapons by the end of this decade it wouldn’t be wise to bet against it.


The general officers were Maj. Gen. Thomas Masiello, commander of ARFL, the U.S. Air Force Research Laboratory, Lt. Gen. Bradley Heithold, head of the Air Force Special Operations Command and General Hawk Carlisle, head of Air Combat Command. The event was the Air and Space Conference organized by the Air Force Association and held earlier this month near Washington, D.C.


Maj. Gen. Masiello outlined a three-pronged approach to airborne laser systems. First will be a defensive system with “tens of kilowatts” of power called SHIELD (for Self-protected HIgh-Energy Laser Demonstration).  It will be powerful enough to protect fighters from missiles and scalable for use as an offensive weapon on larger aircraft such as gunships. It will be demonstrated around 2020, he said. SHIELD will likely use a turret to direct the beam and is also likely to be a podded system rather than fully integrated inside the airframe. It could possibly be carried by an unmanned "wingman” that could help manned fighters operate successfully in highly contested environments.


The SHIELD demo will also look at engaging ground targets on behalf of Lt. Gen. Heithold’s Air Force Special Operations Command (the Air Force equivalent of the better known Navy Seals), using the AC-130 gunship platform, which provides much more space, weight, and power than is available on a fighter aircraft. Heithold noted that an AC-130, could easily accommodate the 5-10,000 pounds of weight that would be required by the laser system and characterized a gunship with a high-energy laser as being just “a couple of years out.” One AC-130W Stinger II gunship, which was earmarked for retirement is now being held aside to support development and testing.


In a presentation on what he called Fifth-Generation Warfare. Air Force General Hawk Carlisle echoed the sentiments of his fellow officers by noting that the era of airborne lasers was  “a lot closer than I think a lot of people think it is.”


General Masiello said that the initial defense system would be followed by a longer-range defensive system with at least 100 kilowatts of power, to be demonstrated in 2022. Lastly,he said, a 300-kilowatt offensive system capable of destroying enemy aircraft and ground targets at long range would be developed.


The low cost of digital imaging devices has allowed them to become popular consumer products.  This low cost is made possible by leveraging a mature processing infrastructure and the ability to fabricate complete focal plane arrays (FPAs) at the wafer scale.  A similar trend is occurring on a smaller scale with thermal imaging technologies.  Microbolometers that are sensitive in the long wave infrared (LWIR) spectrum and are used as a detector in a thermal camera are also manufactured at the wafer scale, and the resulting cost reduction is enabling thermal imagers at consumer‐grade price points.  In contrast, FPAs that respond in the short‐wave and mid‐wave infrared (SWIR and MWIR) spectral bands are currently manufactured using complex and time‐consuming methods that typically involve several manual fabrication steps, including single‐die processes.  Further contributing to high cost is the requirement that MWIR FPAs operate at temperatures < 200 degrees K to achieve good signal‐to‐noise ratios, which requires the use of a cryogenic cooler.


Through its Wafer Scale Infrared Detectors (WIRED) program, the U.S. Defense Advanced Research Projects Agency (DARPA) is asking industry to develop infrared sensors and cameras for low-cost, large-format, and high-performance imaging in the SWIR, MWIR and long-wave infrared (LWIR) spectral bands. They are doing so via a broad-agency announcement, designated DARPA-BAA-15-57.


Specifically of interest are infrared detector materials that can be monolithically processed on traditional readout integrated circuit (ROIC) substrates at the wafer scale. To minimize cost, size, weight and power (SWaP), MWIR FPA detectors must be able to operate at temperatures above 230 degrees K.


DARPA anticipates that through use of current state-of-the-art technology substantial reductions in pixel pitch should be achieved for the same imager format. The program also seeks a better understanding of the fundamental properties, limitations, and benefits of wafer‐scale detector technology.  Finally, WIRED seeks to develop innovative detector technologies in the LWIR spectral band that will enable FPAs to operate without cooling. 


Proposals should have as a goal demonstrating prototype SWIR, MWIR, and LWIR cameras that can be field tested. The DARPA WIRED program is estimated to be worth as much as $40 million, with several contract awards expected. Interested organizations should submit abstracts no later than Oct. 9, 2015, and full proposals no later than Nov. 23, 2015 to the DARPA BAA website.


Combining data obtained from two powerful instruments aboard NASA's Mars Reconnaissance Orbiter (MRO), researchers at the University of Arizona's Lunar and Planetary Laboratory (LPL) determined why the crater shown above is terraced — not bowl shaped, like most craters of this size.

Terraces can form when there are layers of different materials in the planet’s subsurface, such as dirt, ice or rock. When the crater is forming, the shock wave from an object hitting a planet’s surface propagates differently depending on what substrates are beneath the area of impact. If there is a weaker material in one layer, the shock wave can push out that material more easily, and the result is terracing at the interface between the weaker and stronger materials.

Using MRO’s High Resolution Imaging Science Experiment (HiRISE) camera, which is operated out of LPL, the researchers created three-dimensional models of the area's craters, which allowed them to measure the depth of their terraces. The researchers then used MRO’s Shallow Radar (SHARAD), instrument to beam radar pulses to Mars, allowing them to measure the time it took for the radar signals to penetrate the surface’s buried layers and bounce back. Combining the two data sets to measure the radar waves’ speed was a pivotal clue to the layers’ composition.

In this crater’s case, the layers turned out to be ice, and lots of it. Just beneath Mars’ dirt surface, or regolith, the researchers found an enormous slab of water ice, measuring 130 feet thick and covering an area equivalent to that of California and Texas combined.

Although scientists have known for some time about Mars’ icy deposits at its poles and have used them to look at its climatic history, knowledge of icy layers at the planet’s mid-latitudes, analogous to latitudes falling between the Canadian-U.S. border and Kansas on Earth, is something new. And Arcadia Planitia, the area of Mars under study, has a lot of terraced craters,

One possible explanation for the huge amount of water ice is that like the Earth, Mars has had a number of severe climate changes, including several ice ages, in its past. These frequent climate changes are believed to be due to its obliquity — the degree the planet tilts on its axis. Unlike Earth, Mars doesn’t have a large moon to keep it stable. Instead, it wobbles on its axis, and that wobbling leads to the dramatic climatic shifts,,which in turn have led to intermittent ice ages.

The researchers' results have been published online in “Geophysical Research Letters”, a journal of the American Geophysical Union.


The Bloodhound SSC land speed record racing car will make its world debut at East Wintergarden, Canary Wharf, London on Thursday, 24 September before going on public display on Friday and Saturday the 25th and 26th of September from 9am to 5pm.

Bloodhound SSC is a jet- and rocket-powered car designed to reach 1,000 mph on land. It has a slender body of approximately 13.4m in length with two front wheels within the body and two rear wheels mounted externally within wheel fairings. It weighs 7.5 tons and in total the engines produce more than 135,000 horsepower!


The current record stands at 763.035 mph and was set by Andy Green, driver of Bloodhound SSC, when he piloted Thrust SSC in 1997. The Bloodhound SSC land speed racer will be presented in record attempt configuration but without the carbon fiber bodywork on one side, in order to show the car's inner workings. Visitors will see that 98% of the car has been completed including the Rolls-Royce EJ200 jet engine, which is also used to power Europe’s Typhoon military fighter aircraft. In order to accelerate the car to its top speed, each of three Nammo hybrid rockets will provide a thrust of 30kN (6,000 lbs). This will be combined with the thrust from the EJ200 jet engine to generate about 212kN (47,700 lbs of thrust). Nammo rockets are used by the European Space Agency (ESA) to separate the stages of the Ariane 5 satellite launcher. Since the rocket engines gulp down 40 liters of fuel every second, a 542bhp supercharged Jaguar V8 engine is needed just to power the fuel pump.

The Bloodhound SSC is scheduled to undergo runway testing up to 200mph (321km/h) at the Aerohub, Newquay, UK later this year. In 2016 the team will deploy to South Africa to begin high speed testing with the target of first reaching 800mph (1,287km/h) and then 1,000mph (1,609km/h).


Photo source: Semiconductor Manufacturing International Corp. (SMIC), Shanghai China


China has been dominating global economic news for the past couple of weeks as its slowing economy caused jittery investors to sell stocks, resulting in major losses at the world’s premier stock markets.

On the high tech side the market for ICs in China is huge, estimated at well over $150 billion US dollars annually. Domestic IC manufacturing industry sales, however, are less than half of that total and much of it is contributed by foreign companies in China, rather than by local enterprises. Analysts suggest that China has a self-sufficiency rate of less than 10%,as well as a serious shortage of domestic manufacturing capacity and its local foundries on the whole are less than competitive when measured  against their international peers in terms of technology.

The government in China aims to do something about its lack of self-sufficiency in high tech ICs. It is telling local Chinese companies and the news media that it plans to invest as much as 1 trillion yuan (US$161 billion) over 10 years to develop chips, And according to Digitimes Research, an independent business unit and the research arm of Digitimes Inc., a leading high-tech media outlet based in Taiwan, China aims to improve its self-sufficiency rate for ICs in the nation to 40% in 2020, and boost the rate further to 70% in 2025.

As the China government continues to pour capital into the local IC design industry sector, the output value of the sector will reach US$19.49 billion this year, representing a 21.2% increase from US$16.09 billion in 2014, Digitimes Research noted. The output value of China's IC design sector grew at a CAGR of 31% between 2010 and 2014.

Digitimes Research observed that the "National Semiconductor Industry Development Guidelines" and "Made in China 2025," policies published by China's State Council in June 2014 and May 2015, respectively, prescribe a major push in the development of the local IC industry. Digitimes Research notes that "Made in China 2025" clearly outlines that the nation is aiming to raise its self-sufficiency rate for ICs to 40% in 2020, and 70% in 2025.

Based on the "National Semiconductor Industry Development Guidelines," a US$19 billion national industry investment fund has been set up to help local foundries finance the build-up of advanced manufacturing processes, and also to assist local IC firms to form mergers and/or make acquisitions internationally, Digitimes Research said.



Highly sophisticated electronics like infrared instruments and other sensors need to be cooled to precisely detect what they're designed to capture, even to temperatures as low as -320 F (-195 C). The High Power Microcryocooler introduced this week by Lockheed Martin is said to be the industry's highest power density cryocooling system. It delivers more than 150 watts per kilogram, compared to the 30-60 watts per kilogram rating of most space-rated cryocoolers, while maintaining roughly the same power efficiency rating, according to the company. It also weighs under a pound, which is less than half the weight of similar cooling systems, again according to Lockheed Martin.


The company’s previous tiny heat-rejecting device, introduced a year ago, was one-third the size of its predecessors and already the lightest in its class. The new unit packs three times the power density of the prior design.

Smaller cryocoolers mean more affordable satellites and launches. With higher power, the microcryocooler enables larger, more sensitive IR sensors, which is especially useful for very high-resolution images. Beyond enabling compact, higher-power spacecraft payloads the unit will help make possible smaller sensor platforms for manned aircraft and UAVs.



The Martian is an upcoming science fiction film directed by Ridley Scott and based on the 2011 novel of the same name by Andy Weir. The premise is that during a manned mission to Mars, Astronaut Mark Watney is presumed dead after a fierce storm and left behind by his crew. But Watney has survived and finds himself stranded and alone on the hostile planet. With only meager supplies, he must draw upon his ingenuity, wit and spirit to subsist and find a way to signal to Earth that he is alive.


While the film and book are, of course, fiction, NASA is hard at work trying to find a suitable location where humans could land, live and work on Mars. To that end scientists worldwide have been invitedto participate in the First Landing Site/Exploration Zone Workshop for Human Missions to the Surface of Mars. The workshop will be held October 27 to 30, 2015, three weeks after the film’s release, at the Lunar Planetary Institute (LPI) in Houston, TX. NASA hopes it will start the process for choosing sites on Mars that its Mars Reconnaissance Orbiter (MRO) and Mars Odyssey spacecraft along with any future missions over the coming decades could then further image to create better maps and provide valuable scientific data of potential Exploration Zones (EZ). The life expectancy of the existing MRO and Odyssey spacecraft being limited, NASA is eager to take advantage of the remaining operational years of those Martian imagers to gather high resolution maps of potential exploration zones while the spacecraft, already well beyond their design lifetime, are still operational.


Given current mission concepts, an Exploration Zone is a collection of Regions of Interest (ROIs) that are located within approximately 100 kilometers of a centralized landing site (see illustration above). ROIs are areas that are relevant for scientific investigation and/or development/maturation of capabilities and resources necessary for a sustainable human presence. The EZ also contains a landing site and a habitation site that will be used by multiple human crews during missions to explore and utilize the ROIs within the EZ. Potential Exploration Zones will need to offer compelling science research while also providing resources that astronauts can take advantage of during their pioneering of the Red Planet. First explorers are expected to be limited to about 60 miles (100 km) of travel from their landing site due to life support and exploration technology requirements.


The knowledge and capabilities that will be needed to send humans to Mars is being built: spacecraft are monitoring Mars from orbit, rovers are on the surface, the International Space Station is being used to test systems and to learn more about the health impacts of extended space travel, and NASA is developing development and testing the next generation of launch and crew vehicles, including the Space Launch System rocket and Orion crewed spacecraft.


The science of tracking and predicting the path of Hurricanes has improved in accuracy over the years but there has been little improvement in the accuracy of determining how intense the storms are going to be. Now, ten years after Hurricane Katrina formed in the Atlantic, construction of NASA's new hurricane-observing satellites is now underway in Texas. The space agency plans to use a constellation of eight micro-satellites to make accurate measurements of ocean surface winds in and near the eye of a storm throughout the lifecycle of tropical cyclones, typhoons and hurricanes.


The Cyclone Global Navigation Satellite System, or CYGNSS, will be the first to probe the inner core of hurricanes in greater detail to better understand their rapid intensification. The mission is scheduled to launch in late 2016 from Cape Canaveral Air Force Station, Florida, aboard a Pegasus XL rocket.


Previously, measuring wind speed over the oceans from space employed a technique called scatterometry. A radar instrument aboard a satellite sent a signal to the ground, and measured the signal strength reflected back to it. Building both sending and receiving capabilities into a single instrument, however, is more expensive than the method being used on CYGNSS, which is being developed by the University of Michigan, whose role includes satellite design and production and science data processing. The CYGNSS satellites will only receive signals broadcast to them from GPS satellites already orbiting the Earth; it will use GPS signals bounced off of ocean surfaces to measure the height of waves and wind speeds. This data will be shared with NOAA and used to help emergency managers make decisions regarding extreme weather planning.


The use of eight satellites will increase the area on Earth that can be measured. The instruments will be deployed separately around the planet, with successive satellites passing over the same region every 12 minutes. As the CYGNSS and GPS constellations move around the Earth, the interaction of the two systems will result in a new image of wind speed over the entire tropics every few hours, compared to every few days for a single satellite.


Assembly of the first micro-satellite began Aug. 14, with the other seven to follow in the next few weeks. The body of each satellite measures about 20-x-25-x-11 inches and when fully assembled the satellites will each weigh about 64 pounds. With its solar panels deployed, each micro-satellite will have a wingspan of 5.5 feet.



While examining the fluid dynamics behind whisky “mellowing” would appear to be the perfect dissertation topic for a high-living doctoral student, Japanese distillery Suntory is serious about studying the impact of microgravity on its signature products. Serious enough to send five kinds of whisky (along with 40% ethanol as a sixth control sample) via the Kounotori 5 transfer vehicle to the International Space Station (ISS) to mature for two years.

Expected to take off from the Japan Aerospace Exploration Agency's Tanegashima Space Center on August 16, inclement weather caused a postponement of the launch of the Japan Aerospace Exploration Agency (JAXA) H-IIB rocket until tomorrow, Aug. 19, at 7:50 a.m. EDT.

Alcoholic beverages (with the exception of some items like beer) are widely known to develop a mellow flavor when aged for a long time. Although researchers have taken a variety of scientific approaches to understanding the underlying mechanism, they still do not have a full picture of how this occurs. Suntory has hypothesized that “the formation of high-dimensional molecular structure consisting of water, ethanol, and other ingredients in alcoholic beverages contributes to the development of mellowness,” and they have been conducting collaborative research on this topic with the research groups of Professor Shigenao Maruyama of Japan’s Institute of Fluid Science at Tohoku University and Professor Mitsuhiro Shibayama of the Institute for Solid State Physics at the University of Tokyo, as well as with the Japan Synchrotron Radiation Research Institute and Suntory Foundation for Life Sciences. The results of these collaborative research efforts suggest “the probability that mellowness develops by promoted formation of the high-dimensional molecular structure in the alcoholic beverage in environments where liquid convection is suppressed,” according to Suntory.

On the basis of these results, the space experiments will be conducted in the ISS’s Japanese Experiment Module (nicknamed “Kibo”), to verify the effect of the convection-free state created by a microgravity environment to the mellowing of alcoholic beverages. One set of samples consisting of various alcoholic beverages will be stored in a convection-free state in Kibo on the ISS and another set of the identical samples will be stored in Japan for the same period of time. The following methods will be then used to analyze and compare the two sets of samples.

  1.     Measurement of substance diffusion coefficient with the use of a phase-shifting interferometer in cooperation with the Institute of Fluid Science, Tohoku University.

  2.     Detection of high-dimensional structure by small angle X-ray scattering, in cooperation with the Japan Synchrotron Radiation Research Institute and the Institute for Solid State Physics, the University of Tokyo.

  3.     Measurement of substance diffusion with the use of the NMR method, in cooperation with the Suntory Foundation for Life Sciences.

With less gravity suppressing convection, there’s a possibility that the low-gravity environment will accelerate the whisky’s aging, causing a two-year batch to taste like it has been aged for a ten years. The samples’ age ranges from a freshly distilled whisky to a 21-year single malt.  For a variety of reasons (launch weight restrictions, etc.) the whisky is stored in glass flasks rather than wooden barrels.

The unpiloted Kounotori cargo craft will also be loaded with more than 4.5 tons of other research materials and supplies, including water, spare parts and experiment hardware for the six-person space station crew.


Travelling wave tubes (TWT) amplify signals by exchanging kinetic energy in the electron beam (shown as a blue line) with electromagnetic energy in the signal. This figure represents a cutaway view of a TWT with all of the critical components: electron gun, magnetic circuit, electron collector, and the windows that keep the vacuum inside the tube while letting the signals flow in and out.(Source: DARPA)

Your first reaction to the idea that DARPA is trying to develop a new generation of more capable Vacuum Electron Devices (VED) might well be: “What is this, Back to the Future?  But hold on, put that DeLorean into neutral for a second. While it is true that we now live in a silicon not vacuum tube era, VEDs are critical components for Department of Defense (DoD) systems that require high power, wide bandwidth, and high efficiency. Traveling wave tubes (TWTs, pictured above) not solid-state amplifiers generate the strong electromagnetic signals in communication satellites because of their exceptional in-orbit reliability and high power efficiency. Space-qualified TWTs have a mean time to failure (MTTF) of over ten million hours with power efficiencies greater than 70 percent.

VED amplifiers also can exhibit wide operating bandwidths of over three octaves, and high output power levels up to thousands of watts from a single device. Higher power VED operation yields RF signals that are “louder” and thereby harder to jam and otherwise interfere with. What’s more, the unique ability of VEDs to generate high-frequency signals at chip-melting operating power makes possible modern aviation radar systems for navigation and collision avoidance. It is estimated that there are more than 200,000 VEDs now in service in the DoD, powering critical communications and radar systems.

While most VEDs in common use today (TWTs, klystrons, crossed-field amplifiers, magnetrons, gyrotrons and others) were invented in the first half of the 20th century, ongoing development efforts have produced dramatic advances in their performance and reliability. So, notwithstanding the popular notion that vacuum electronics are old-fashioned, the incentive to overcome technical and cost barriers to develop next-generation VEDs has been getting stronger.

With its new Innovative Vacuum Electronic Science and Technology (INVEST) program, DARPA aims to develop the science and technology base for a new generations of more capable VEDs. The DARPA INVEST program focuses on vacuum tubes operating at millimeter-wave frequencies above 75 GHz. Those awarded contracts under the program will take on fundamental research projects in areas that include physics-based modeling and simulation of VEDs, innovative component design, electron emission processes, and advanced manufacturing; this last element being important because as frequencies increase and you are dealing with the tiny size and precise alignment of millimeter-wave VED components, among them high-current-density cathodes, tiny vacuum envelopes, and the miniature parts that extract the RF signals amplified inside the component, you can’t use conventional manufacturing techniques.

A just-published Broad Agency Announcement (BAA) invites the technical community to submit proposals for research that would take VED technology to new heights of power and frequency. You can find DARPA-BAA-15-40 at FedBizOpps. Gov,  http://go.usa.gov/3HqK9.


Artist's impression of new racing wheelchair


Following up on its success at the Sochi Winter Olympics--the U.S. two-man bobsled team took home a bronze medal in a bobsled designed by BMW North America --BMW has announced plans to develop a new racing wheelchair for use by athletes of the U.S. Paralympics Track and Field Team in the Rio 2016 Paralympic Games.


BMW’s wholly-owned Designworks consultancy headquartered in California will collaborate with the U.S. Paralympics Track and Field team in identifying and addressing the need for potential improvements in the team’s racing wheelchair.


Although still under development, the new wheelchair’s improvements will include a complete redesign of its chassis, application of BMW-developed aerodynamic efficiencies, enhanced athlete restraint, carbon fiber durability and steering and braking advancements. The company reports it has been researching and learning know- how to develop these new machines for over a year. The racing wheelchair is slated to be delivered to U.S. Paralympics track and field elite racers in early 2016 to allow the athletes time to train and practice with their new BMW wheelchair before the September start of the games, which will follow the Summer Olympic Games in Rio de Janeiro.

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