Satellites for peat sake - Peatlands play vital role in curbing climate change

                         Peatlands play vital role in curbing climate change Credit: JHU
Peatlands make up just 3% of land but capture twice as much carbon as all forests combined.

They are also an important source of drinking water and provide a home to many rare and threatened animals and plants.

Ecosystems work best when left intact but these wetland areas are being threatened by human exploitation, resulting in vast carbon emissions, frequent and uncontrollable fires and loss of valuable landscapes.

                                            Handheld devices for collecting ground data

Rezatec in Oxfordshire, UK, supported by ESA’s Integrated Applications Promotions programme, in the Peat spotter project will give landowners an easier and cheaper way of calculating the potential economic value of conserving or restoring their peatlands and monitoring the results of their investment.

“Peat spotter helps landowners to manage their peat resource more sustainably through mapping the area, measuring the carbon it contains and monitoring how its integrity is changing over time,” says Patrick Newton, CEO of Rezatec.

To do this, satellite imagery is used to locate and create initial mappings of peatlands. This information is enriched with ground data collected by field agents using handheld devices.

An app prompts users in the field for measurements, satnav adds location information, and the data are then sent directly to a centralised office via satcom for analysis.

The new approach is a cost-effective way of measuring peat extent and how intact it is over wide and potentially remote areas that are otherwise expensive to measure or inaccessible from the ground.

Rezatec expects water companies, conservation groups and those using typically state-owned land for uses such as plantations to sign up for this service.

Peatlands are an important source of drinking water. Water companies using these resources can significantly reduce the water treatment necessary to meet drinking water standards if they are able to identify areas of degraded peatland and make restoration efforts at source.

Water derived from degraded peatlands can contain raised levels of dissolved organic carbon causing significant discolouration.

On land that is typically used for plantations, peat assets are included in the measurement of the greenhouse gas balance, but only through a rough calculation.

                                                     Deforestation damages peatlands

Making it cheaper and easier to locate and monitor peatlands will make it simpler to calculate the economic value of conserving and restoring these areas and, in turn, this can be positive for society, the economy and the environment.

Within the mobile device apps Rezatec includes: guides to help identify flora and fauna, videocam monitoring of borders, photo uploading, alerts when levels are breached, and fire mapping.

“This innovative use of satellite data has far-reaching benefits for the space industry and the wider UK economy,” notes Alan Brunstrom, head of the Service Business Office in ESA’s Integrated Applications Promotion programme.

“Perhaps more importantly, it demonstrates how the scientific analysis of ‘big data’ can benefit the environment and, in this particular scenario, provide valuable information to allow sustainable peatland management practices on a global scale.”

Source: JHU

Tailored 'activity coaching' by smartphone

Tailored activity monitoring. Credit: Image courtesy of University of Twente

Today's smartphone user can obtain a lot of data about his or her health, thanks to built-in or separate sensors. Researcher Harm op den Akker of the University of Twente (CTIT Institute) now takes this health monitoring to a higher level. Using the system he developed, the smartphone also acts as an 'activity coach': it advices the user to walk or take a rest. In what way the user wants to be addressed, is typically something the system learns by itself. Op den Akker conducted his research at Roessingh Research and Development in Enschede. October 17, he defends his PhD-thesis.

The new telemedicine system was tested for three months, among a group of COPD patients -- a chronic lung disease. For these patients, physical activity is very important but it can also lead to an oppressed feeling and thus, to over-cautiousness. Using the coaching system of Van den Akker, the patients carry a small movement sensor and a smartphone. The system calculates if it is advisable to take a rest or, on the other hand, have a walk. The system is 'context aware': it looks at the time of day, the weather, the surroundings of the patient and determines if the time is right for taking some exercise.

Tone of voice

In addition, the system knows how the patient wants to be addressed. Some people don't mind an imperative tone of voice 'go for a 10 minutes' walk', others prefer a more friendly advice: 'what if you would take a walk in the park?' Op den Akker designed learning algorithms for this: the system learns the preferences of the user by itself. Future versions of the system may not use text messages anymore, but an 'avatar' on the screen, enabling interaction with the user as well. For this, Op den Akker has started starting cooperation with the Human Media Interaction group of the University of Twente.

Roessingh Research & Development (RRD) is the research department of Roessingh rehabilitation centre in Enschede, The Netherlands. RRD closely cooperates with the University of Twente in many projects. Op den Akker conducted his research at RRD and UT's CTIT Institute, under supervision of Hermie Hermens, Professor in Neuromuscular Control and Telemedicine. A spin-off company of the university, Inertia Technology, developed the movement sensor used in this project.

Op den Akker's PhD-thesis is titled 'Smart tailoring of real-time physical activity coaching systems'.

Source: University of Twente

Smartphone sensors leave trackable fingerprints

Example demonstrating how accelerometer data shared with separate traffic and health applications could indicate Bob's location. Credit: Image courtesy of University of Illinois College of Engineering

Fingerprints -- those swirling residues left on keyboards and doorknobs -- are mostly invisible. They can affirm your onetime presence, but they cannot be used to track your day-to-day activities.

They cannot tell someone in real time that after exercising at the gym, you went to office in a bus and played video games during lunch. But what if our hand-held electronics are leaving real-time fingerprints instead? Fingerprints that are so intrinsic to the device that, like our own, they cannot be removed?

Research by Associate Professor Romit Roy Choudhury and graduate students Sanorita Dey and Nirupam Roy has demonstrated that these fingerprints exist within smartphone sensors, mainly because of imperfections during the hardware manufacturing process.

In some ways, it's like cutting out sugar cookies. Even using the same dinosaur-shaped cutter, each cookie will come out slightly different: a blemish here, a pock there. For smartphone sensors, these imperfections simply occur at the micro- or nanoscale.

Their findings were published at the Network and Distributed System Security Symposium (NDSS), a major conference on wireless and web security, held last February in San Diego. 

The research also won the best poster award at the HotMobile international workshop in 

2013.

The researchers focused specifically on the accelerometer, a sensor that tracks three-dimensional movements of the phone -- essential for countless applications, including pedometers, sleep monitoring, mobile gaming -- but their findings suggest that other sensors could leave equally unique fingerprints.

"When you manufacture the hardware, the factory cannot produce the identical thing in millions," Roy said. "So these imperfections create fingerprints."

Of course, these fingerprints are only visible when accelerometer data signals are analyzed in detail. Most applications do not require this level of analysis, yet the data shared with all applications -- your favorite game, your pedometer -- bear the mark. Should someone want to perform this analysis, they could do so.

The researchers tested more than 100 devices over the course of nine months: 80 standalone accelerometer chips used in popular smartphones, 25 Android phones, and 2 tablets.

The accelerometers in all permutations were selected from different manufacturers, to ensure that the fingerprints weren't simply defects resulting from a particular production line.

With 96 percent accuracy, the researchers could discriminate one sensor from another.

"We do not need to know any other information about the phone -- no phone number or SIM card number," Dey said. "Just by looking at the data, we can tell you which device it's coming from. It's almost like another identifier."

In the real world, this suggests that even when a smartphone application doesn't have access to location information (by asking "this application would like to use your current location"), there are other means of identifying the user's activities. It could be obtained with an innocuous-seeming game or chatting service, simply by recording and sending accelerometer data. There are no regulations mandating consent.

To collect the data, the researchers -- as with any would-be attacker -- needed to sample the accelerometer data. Each accelerometer was vibrated using a single vibrator motor -- like those that buzz when a text message is received -- for two-second intervals. During those periods, the accelerometer detected the movement and the readings were transmitted to a supervised-learning tool, which decoded the fingerprint.

"Even if you erase the app in the phone, or even erase and reinstall all software," Roy said, "the fingerprint still stays inherent. That's a serious threat."

At this point, however, there is no absolute solution. Smartphone cases made of rubber or plastic do little to mask the signal. Deliberately injecting white noise in the sensor data can smudge the fingerprint, but such noise can also affect the operation of the application, making your pedometer inaccurate and functionally useless.

If accelerometer data were processed directly on the phone or tablet, rather than on the cloud, the fingerprint could be scrubbed before sending information to the application.

That is, the pedometer application might only receive basic information like "300 steps taken," rather than receiving the raw accelerometer data. This, however, imposes a load on the phone's processor and, more importantly, reduces the phone's battery life.

The research also suggests that other sensors in the phone -- gyroscopes, magnetometers, microphones, cameras, and so forth -- could possess the same types of idiosyncratic differences. So even if, at a large scale, the accuracy of accelerometer fingerprints diminishes, when combined with prints from other sensors, an attack could be even more precise.

"Imagine that your right hand fingerprint, by some chance, matches with mine," Roy Choudhury said. "But your left-hand fingerprint also matching with mine is extremely unlikely. So even if accelerometers don't have unique fingerprints across millions of devices, we believe that by combining with other sensors such as the gyroscope, it might still be possible to track a particular device over time and space."

For smartphone users and e-book readers, smartwatch wearers and tablet devotees, perhaps the most critical take-home message, in the short run anyway, is the importance of vigilance.

"Don't share your accelerometer data without thinking about how legitimate or how secure that application is," Dey said. "Even if it's using only the sensor data, still it can attack you in some way. The consumer should be aware."

Source: University of Illinois College of Engineering

A medical lab for the home

Microchip for the electrochemical detection of markers. Credit: © Fraunhofer FIT

Fraunhofer FIT demonstrates a mobile wireless system that monitors the health of elderly people in their own homes, using miniature sensors. Besides non-invasive sensors this platform integrates technology to take a blood sample and to determine specific markers in the patient's blood. At its core is the home unit, a compact device located in the patient's home. It incorporates the necessary software as well as sensors and the analytical equipment.

For years, cardiac diseases have been the most important cause of death globally. Mobile assistance systems that monitor vital parameters, e.g. blood pressure or heart rate, of risk patients in their homes could make their lives safer and more satisfying. A platform supporting this kind was developed and tested by researchers from Fraunhofer FIT, the Berlin Charité, T-Systems and several international partners.

Besides non-invasive sensors this platform integrates technology to take a blood sample and to determine specific markers in the patient's blood while the patient is at home. At its core is the home unit, a compact device located in the patient's home. It incorporates the necessary software as well as sensors and the analytical equipment. Wearable sensors for measuring vital parameters can be linked to the home unit, e.g. a pulse oximeter with a Bluetooth module in the patient's ear or a blood pressure monitor that sends its data to the system via WLAN. Using a nanopotentiostat, an electrochemical sensor, the system can measure the patient's glucose, lactate or cholesterol level. In addition, a fluorescence sensor using a laser diode captures the concentration of several cardiac markers.

To detect the risk-indicating markers in the blood, the patient uses a cartridge that she fills with a drop of blood from a prick in her finger. The cartridge is equipped with a microchip and also specially designed, so that the markers in the blood can be detected. "Miniaturized sensors in the home unit, which can detect traces of the markers down to the nano level, analyze the blood sample," says Professor Harald Mathis, head of the department 

'Biomolecular Optical Systems' of the Fraunhofer Institute for Applied Information 

Technology FIT.

The home unit aggregates the sensor data and sends the results to the patient's doctor or a medical center via secure Internet connection. A smartphone app presents the health data and the physician's feedback to the patient.

The system was developed by Fraunhofer FIT in cooperation with Charité and T-Systems Deutschland in the BMBF/EU-funded project Nanoelectronics for Mobile AAL Systems -- MAS.

Source: Fraunhofer-Institut fuer Angewandte Informationstechnik (FIT)

Scientists twist radio beams to send data: Transmissions reach speeds of 32 gigibits per second

Graphic showing the intensity of the radio beams after twisting.
Credit: Courtesy of Alan Willner / USC Viterbi

Building on previous research that twisted light to send data at unheard-of speeds, scientists at USC have developed a similar technique with radiowaves, reaching high speeds without some of the hassles that can go with optical systems.

The researchers, led by electrical engineering professor Alan Willner of the USC Viterbi School of Engineering, reached data transmission rates of 32 gigabits per second across 2.5 meters of free space in a basement lab at USC.

For reference, 32 gigabits per second is fast enough to transmit more than 10 hour-and-a-half-long HD movies in one second and is 30 times faster than LTE wireless.

"Not only is this a way to transmit multiple spatially collocated radio data streams through a single aperture, it is also one of the fastest data transmission via radio waves that has been demonstrated," Willner said.

Faster data transmission rates have been achieved -- Willner himself led a team two years ago that twisted light beams to transmit data at a blistering 2.56 terabits per second -- but methods to do so rely on light to carry the data.

"The advantage of radio is that it uses wider, more robust beams. Wider beams are better able to cope with obstacles between the transmitter and the receiver, and radio is not as affected by atmospheric turbulence as optics," Willner said.

Willner is the corresponding author of an article about the research that will be published in Nature Communications on Sept. 16. The study's co-lead authors Yan Yan and Guodong Xie are both graduate students at USC Viterbi, and other contributors came from USC, the University of Glasgow, and Tel Aviv University.

To achieve the high transmission rates, the team took a page from Willner's previous work and twisted radio beams together. They passed each beam -- which carried its own independent stream of data -- through a "spiral phase plate" that twisted each radio beam into a unique and orthogonal DNA-like helical shape. A receiver at the other end of the room then untwisted and recovered the different data streams.

"This technology could have very important applications in ultra-high-speed links for the wireless 'backhaul' that connects base stations of next-generation cellular systems," said Andy Molisch of USC Viterbi. Molisch, whose research focuses on wireless systems, co-designed and co-supervised the study with Willner.

Future research will focus on attempting to extend the transmission's range and capabilities.

The work was supported by Intel Labs University Research Office and the DARPA InPho (Information in a Photon) Program.

Source: University of Southern California

World's first ZigBee-based inter-satellite comms system

This image depicts VELOX-I before and after deployment and a picosatellite. Credit: Shuanglong Xie, Guo Xiong Lee, Kay-Soon Low, Erry Gunawan, 2014

Engineers at the Nanyang Technological University in Singapore have successfully piloted the world's first ZigBee-based inter-satellite communication system.

The team at the Satellite Research Centre launched the VELOX-I, which consists of a nanosatellite weighing 3.5 kg and a piggyback picosatellite weighing 1.5 kg, from the two highest points on campus. Both miniature satellites were configured with a ZigBee wireless network and equipped with small sensor nodes that perform functions such as local sensing, distributed computing and data-gathering.

Designed to evaluate the performance of wireless sensor networks (WSNs) in space, the experiment marks a breakthrough in aeronautical engineering. After conducting Received Signal Strength Indicator tests on the satellites' radio frequency modules, a maximum range of 1 km was found to be achievable for inter-satellite communication in the campus environment. An even longer communication range can be expected in free space, due to the absence of signal attenuation caused by fading and diffraction.

To estimate the range of inter-satellite communication in free space, the team applied a link budget analysis based on the Friis transmission equation, deriving an average theoretical distance of 4.186 km and a maximum of 15.552 km. Published in the special issue of Unmanned Systems, these findings present a compelling case for further studies into inter-satellite communication systems with more complex designs.

In addition to their high performance in inter-satellite communication, WSNs are also remarkably suitable for intra-satellite communication. The team found that by replacing internally wired connections with wireless links, a satellite's mass could be reduced by as much as 10%. With the twin pressures of minimising development costs and maximising risk diversification imposing major constraints on satellite design, the production of comprehensive yet lightweight systems could benefit significantly from WSNs.

Although WSNs have been used in a wide range of applications in recent years, their use in space applications has, until now, remained limited. The Singaporean team's data-driven survey has established a sound platform for future formation-flying satellite missions, and seems poised to create subsequent revolutions in space.

Source: World Scientific

Li-fi protocol allows use of the Internet at the speed of light

Sisoft Company in Mexico has developed a technology that can illuminate a large work space, an auditorium or an office, while providing full mobile internet to every device that comes into the range of the light spectrum. Credit: SISOFT

Sisoft Company in Mexico has developed a technology that can illuminate a large work space, an auditorium or an office, while providing full mobile internet to every device that comes into the range of the light spectrum.

The Mexican group managed to transmit audio, video and Internet across the spectrum of light emitted by LED lamps. This new technology, called Li-Fi or light fidelity, is presented as an alternative to Wi-Fi because it will maximize the original provided speed of the internet to offer safer data transfer and a transfer rate of up to 10 gigabytes per second.

The Li-Fi device circulates data via LEDs that emit an intermittent flicker at a speed imperceptible to the human eye. "As Wi-Fi uses cables to spread our connections, wireless transmission Li-Fi uses LED lamps that emit high brightness light," said Arturo Campos Fentanes, CEO of Sisoft in Mexico.

Another advantage in comparison to Wi-Fi is that there is no way to hack the signal since the internet is transmitted by light, there is no way to "steal it." Furthermore, it can be installed in hospitals areas that use radiation apparatus and generally block or distort internet signal, Campos Fentanes said.

With this new technology expansion through the market is seeked, with lower costs and a service increased by five thousand percent internet speed. Currently in Mexico the highest transfer rate is 200 megabytes per second. Just to get an idea, with Li-Fi you could quickly download an entire HD movie in just 45 seconds.

Also known as visible light communications (VLC), this technology began with an internet speed of two Gigabits per second, but Sisoft along with researchers from the Autonomous Technological Institute of Mexico (ITAM) adapted the system to be multiplied five times.

Campos Fentanes explained that the first experiments were conducted with audio, in which a cable is connected via 3.5 mm audio Jack from a smartphone to a protoboard table to transform the auditory signal in optical waves. That way a special emitter transmits data across the spectrum of light generated by an LED lamp and is captured by a receptor located in a speaker that reproduces sound.

For wireless internet transmission, the mechanics is similar. The station developed by Sisoft of Mexico stands above the router device that distributes the internet signal and a lamp-LED is incorporated to maximize the speed of data transfer. Light will emulate an antenna, but only the electronic apparatus that has the receptor for the "optical audio" signal and is inside the range of the halo of light will have a connection. 

Source: Investigación y Desarrollo

That smartphone is giving your thumbs superpowers

While neuroscientists have long studied brain plasticity in expert groups--musicians or video gamers, for instance--smartphones present an opportunity to understand how regular life shapes the brains of regular people. Credit: © Antonioguillem / Fotolia

When people spend time interacting with their smartphones via touchscreen, it actually changes the way their thumbs and brains work together, according to a report in the Cell Press journal Current Biology on December 23. More touchscreen use in the recent past translates directly into greater brain activity when the thumbs and other fingertips are touched, the study shows.

"I was really surprised by the scale of the changes introduced by the use of smartphones," says Arko Ghosh of the University of Zurich and ETH Zurich in Switzerland. "I was also struck by how much of the inter-individual variations in the fingertip-associated brain signals could be simply explained by evaluating the smartphone logs."

It all started when Ghosh and his colleagues realized that our newfound obsession with smartphones could be a grand opportunity to explore the everyday plasticity of the human brain. Not only are people suddenly using their fingertips, and especially their thumbs, in a new way, but many of us are also doing it an awful lot, day after day. Not only that, but our phones are also keeping track of our digital histories to provide a readymade source of data on those behaviors.

Ghosh explains it this way: "I think first we must appreciate how common personal digital devices are and how densely people use them. What this means for us neuroscientists is that the digital history we carry in our pockets has an enormous amount of information on how we use our fingertips (and more)."

While neuroscientists have long studied brain plasticity in expert groups--musicians or video gamers, for instance--smartphones present an opportunity to understand how regular life shapes the brains of regular people.

To link digital footprints to brain activity in the new study, Ghosh and his team used electroencephalography (EEG) to record the brain response to mechanical touch on the thumb, index, and middle fingertips of touchscreen phone users in comparison to people who still haven't given up their old-school mobile phones.

The researchers found that the electrical activity in the brains of smartphone users was 

enhanced when all three fingertips were touched. In fact, the amount of activity in the cortex of the brain associated with the thumb and index fingertips was directly proportional to the intensity of phone use, as quantified by built-in battery logs. The thumb tip was even sensitive to day-to-day fluctuations: the shorter the time elapsed from an episode of intense phone use, the researchers report, the larger was the cortical potential associated with it.

The results suggest to the researchers that repetitive movements over the smooth touchscreen surface reshape sensory processing from the hand, with daily updates in the brain's representation of the fingertips. And that leads to a pretty remarkable idea: "We propose that cortical sensory processing in the contemporary brain is continuously shaped by personal digital technology," Ghosh and his colleagues write.

What exactly this influence of digital technology means for us in other areas of our lives is a question for another day. The news might not be so good, Ghosh and colleagues say, noting evidence linking excessive phone use with motor dysfunctions and pain.

Source: Cell Press

Breezy science, plant studies and more head to space station on SpaceX-4

This Artist's rendering of the ISS-RapidScat instrument (inset), will measure ocean surface wind speed and direction and help improve weather forecasts. It will be installed on the end of the station's Columbus laboratory. Credit: NASA/JPL-Caltech/Johnson Space Center

Imagine a dragon flying through the heavens on mighty, outstretched wings. The majestic beast knows the currents of winds and how to harness their power as it soars above the clouds. SpaceX's real Dragon -- the company's spacecraft that transports supplies and science to the International Space Station (ISS) -- will deliver, and later return, new technology, biology and biotechnology and Earth and space science research to the orbiting outpost.

One of the new Earth science investigations heading into orbit is the ISS-Rapid Scatterometer (ISS-RapidScat). ISS-RapidScat monitors ocean winds from the vantage point of the space station. This space-based scatterometer is a remote sensing instrument that uses radar pulses reflected from the ocean's surface at different angles to calculate surface wind speed and direction. This information will be useful for weather forecasting and hurricane monitoring.

"We'll be able to see how wind speed changes with the time of day," said Ernesto Rodríguez, principal investigator for ISS-RapidScat at NASA's Jet Propulsion Laboratory in Pasadena, California. "ISS-RapidScat will link together all previous and current scatterometer missions, providing us with a more complete picture of how ocean winds change. Combined with data from the European ASCAT scatterometer mission, we'll be able to observe 90 percent of Earth's surface at least once a day, and in many places, several times a day."

In addition to improving weather models, RapidScat enhances measurements from other international scatterometers by cross-checking their data. Due to its unique orbit, RapidScat will observe different parts of the planet at different times of day. This allows the instrument to track the effects of the sun on ocean winds as the day progresses. Because the instrument reuses leftover hardware originally built to test parts of the now inoperable NASA QuikScat scatterometer, this investigation demonstrates a unique way to replace an instrument aboard an aging satellite.

New biomedical hardware launching on SpaceX's fourth commercial resupply mission to the space station will facilitate prolonged biological studies in microgravity. The Rodent Research Hardware and Operations Validation (Rodent Research-1) investigation provides a platform for long-duration rodent experiments in space. These experiments examine how microgravity affects animals, providing information relevant to human spaceflight, discoveries in basic biology and knowledge that may have direct impact toward human health on Earth. Rodent Research-1 tests the operational capabilities of the new hardware system, including the transporter, rodent habitat and access unit.

Because rodents experience developmental stages and aging processes more quickly than humans, they make ideal research model organisms to infer information about disease development and progression in humans. Model organisms are non-human species with characteristics that allow them easily to be maintained, reproduced and studied in a laboratory.

"In the coming years, rodent studies conducted aboard the space station will gather foundational data that will help advance human space exploration and provide new opportunities to improve quality of life on Earth," said Ruth Globus, Ph.D., Rodent Research Project scientist and researcher in the Space Biosciences Division at NASA's Ames Research Center in Moffett Field, California.

Another biological research investigation aboard Dragon includes a new plant study. The Biological Research in Canisters (BRIC) hardware has supported a variety of plant growth experiments aboard the space station. The BRIC-19 investigation, the first to collect data for the geneLAB research platform, will focus on the growth and development of Arabidopsis thaliana seedlings in microgravity. A. thaliana is a small flowering plant related to cabbage, and its genetic makeup is simple and well-understood by the plant biology community. This knowledge offers easy recognition of any changes that occur as a result of microgravity adaptation.

Plant development on Earth is impacted by mechanical forces such as wind or a plant's own weight. Researchers hope to get a better understanding of how the growth responses of plants are altered by the absence of these forces when grown in microgravity.

The BRIC hardware helps to maximize research and minimize space and crew time since it does not use power to operate and the canister is the size of a bread box. This study may add to the collective body of knowledge about basic plant growth phenomena and could help improve farming practices on Earth.

In addition to Earth and biological science studies, several new technology demonstrations are making their way to the space station. One of those, known as the Special Purpose Inexpensive Satellite, or SpinSat, will test how a small satellite moves and positions itself in space using new thruster technology. It will launch into orbit from the space station through the new Cyclops small satellite deployer, also known as the Space Station Integrated Kinetic Launcher for Orbital Payload Systems (SSIKLOPS).

SpinSat is a spherical satellite measuring 22 inches in diameter. It will test advanced thruster technology that uses a new class of non-pyrotechnic materials known as Electrically-Controlled Solid Propellants (ESP). ESPs are ignited only by electric current.

Researchers can use high-resolution atmospheric data captured by SpinSat to determine the density of the thermosphere, one of the uppermost layers of the atmosphere. With better knowledge of the thermosphere, engineers and scientists can refine satellite and telecommunications technology.

Another new technology demonstration catching a ride on the Dragon is the 3-D Printing In Zero-G Technology Demonstration (3-D Printing In Zero-G), which will be the first ever 3-D printer in space. Additive manufacturing could enable parts to be manufactured quickly and cheaply in space, instead of waiting for the next cargo resupply vehicle delivery. The research team also can gain valuable insight into improving 3-D printing technology on Earth by demonstrating it in microgravity.

With so many new investigations that directly impact human life, this Dragon's delivery is helping the space station make discoveries off the Earth, for the Earth.

Source: Nasa

First broadband wireless connection ... to the moon: Record-shattering Earth-to-Moon uplink

The ground terminal, with the sun reflecting off of the solar windows of the uplink telescopes, is shown. Credit: Robert LaFon, NASA/GSFC

If future generations were to live and work on the moon or on a distant asteroid, they would probably want a broadband connection to communicate with home bases back on Earth. They may even want to watch their favorite Earth-based TV show. That may now be possible thanks to a team of researchers from the Massachusetts Institute of Technology's (MIT) Lincoln Laboratory who, working with NASA last fall, demonstrated for the first time that a data communication technology exists that can provide space dwellers with the connectivity we all enjoy here on Earth, enabling large data transfers and even high-definition video streaming.

At CLEO: 2014, being held June 8-13 in San Jose, California, USA, the team will present new details and the first comprehensive overview of the on-orbit performance of their record-shattering laser-based communication uplink between the moon and Earth, which beat the previous record transmission speed last fall by a factor of 4,800. Earlier reports have stated what the team accomplished, but have not provided the details of the implementation.

"This will be the first time that we present both the implementation overview and how well it actually worked," says Mark Stevens of MIT Lincoln Laboratory. "The on-orbit performance was excellent and close to what we'd predicted, giving us confidence that we have a good understanding of the underlying physics," Stevens says.

The team made history last year when their Lunar Laser Communication Demonstration (LLCD) transmitted data over the 384,633 kilometers between the moon and Earth at a download rate of 622 megabits per second, faster than any radio frequency (RF) system. They also transmitted data from Earth to the moon at 19.44 megabits per second, a factor of 4,800 times faster than the best RF uplink ever used.

"Communicating at high data rates from Earth to the moon with laser beams is challenging because of the 400,000-kilometer distance spreading out the light beam," Stevens says. "It's doubly difficult going through the atmosphere, because turbulence can bend light -- causing rapid fading or dropouts of the signal at the receiver."

To outmaneuver problems with fading of the signal over such a distance, the demonstration uses several techniques to achieve error-free performance over a wide range of optically challenging atmospheric conditions in both darkness and bright sunlight. A ground terminal at White Sands, New Mexico, uses four separate telescopes to send the uplink signal to the moon. Each telescope is about 6 inches in diameter and fed by a laser transmitter that sends information coded as pulses of invisible infrared light. The total transmitter power is the sum of the four separate transmitters, which results in 40 watts of power.

The reason for the four telescopes is that each one transmits light through a different column of air that experiences different bending effects from the atmosphere, Stevens says. This increases the chance that at least one of the laser beams will interact with the receiver, which is mounted on a satellite orbiting the moon. This receiver uses a slightly narrower telescope to collect the light, which is then focused into an optical fiber similar to fibers used in terrestrial fiber optic networks.

From there, the signal in the fiber is amplified about 30,000 times. A photodetector converts the pulses of light into electrical pulses that are in turn converted into data bit patterns that carry the transmitted message. Of the 40-watt signals sent by the transmitter, less than a billionth of a watt is received at the satellite -- but that's still about 10 times the signal necessary to achieve error-free communication, Stevens says.

Their CLEO: 2014 presentation will also describe how the large margins in received signal level can allow the system to operate through partly transparent thin clouds in Earth's atmosphere, which the team views as a big bonus.

"We demonstrated tolerance to medium-size cloud attenuations, as well as large atmospheric-turbulence-induced signal power variations, or fading, allowing error-free performance even with very small signal margins," Stevens says.

While the LLCD design is directly relevant for near-Earth missions and those out to Lagrange points -- areas where the forces between rotating celestial bodies are balanced, making them a popular destination for satellites -- the team predicts that it's also extendable to deep-space missions to Mars and the outer planets.

Presentation SM4J.1, titled "Overview and On-orbit Performance of the Lunar Laser Communication Demonstration Uplink," will take place Monday, June 9.

Source: The Optical Society

Gecko grippers get a microgravity test flight

Scientists at NASA's Jet Propulsion Laboratory in Pasadena, California, are working on adhesive gripping tools that could grapple objects such as orbital debris or defunct satellites that would otherwise be hard to handle.
Credit: Image courtesy of NASA/Jet Propulsion Laboratory

There are no garbage trucks equipped to leave the atmosphere and pick up debris floating around Earth. But what if we could send a robot to do the job?

Scientists at NASA's Jet Propulsion Laboratory in Pasadena, California, are working on adhesive gripping tools that could grapple objects such as orbital debris or defunct satellites that would otherwise be hard to handle.

The gecko gripper project was selected for a test flight through the Flight Opportunities Program of NASA's Space Technology Mission Directorate. As a test, researchers used the grippers in brief periods of weightlessness aboard NASA's C-9B parabolic flight aircraft in August.

"Orbital debris is a serious risk to spacecraft, including the International Space Station," said Aaron Parness, a JPL robotics researcher who is the principal investigator for the grippers. "This is definitely a problem we're going to have to deal with. Our system might one day contribute to a solution."

The gripping system developed by Parness and colleagues was inspired by geckos, lizards that cling to walls with ease. Geckos' feet have branching arrays of tiny hairs, the smallest of which are hundreds of times thinner than a human hair. This system of hairs can conform to a rough surface without a lot of force. Although researchers cannot make a perfect replica of the gecko foot, they have put "hair" structures on the adhesive pads of the grippers.

The synthetic hairs, also called stalks, are wedge-shaped and have a slanted, mushroom-shaped cap. When the gripping pad lightly touches part of an object, only the very tips of the hairs make contact with that surface.

"The stickiness of the grippers can be turned on and off, by changing the direction in which you pull the hairs," Parness said.

To get the gripper to stick to a surface, force is applied to the adhesive pad material in a manner that makes the hairs bend. This increases the real area of contact between the hairs and the surface, which corresponds to greater adhesion. When the force is relaxed and the hairs go back to being upright, this process turns off the stickiness.

A phenomenon called van der Waals forces, named for Nobel Prize-winning physicist Johannes Diderik van der Waals, explains the non-permanent stickiness of the grippers, as well as gecko feet. These temporary adhesive forces happen because electrons orbiting the nuclei of atoms are not evenly spaced, creating a slight electrical charge. Such forces persist even in extreme temperature, pressure and radiation conditions.

"The reliability of van der Waals forces, even in severe environments, makes them particularly useful for space applications," Parness said.

"The system could grapple objects in space that are spinning or tumbling, and would otherwise be hard to target," he said.

In the recent tests, the grippers were able to grapple a 20-pound cube as it floated. The grippers also were able to grapple a researcher wearing a vest made of spacecraft material panels, representing a 250-pound "object." 

Members of the research team held the device with adhesive pads during the test, but the eventual idea is to integrate the grippers into a robotic arm or leg.

In total, the grippers have been tested on more than 30 spacecraft surfaces at JPL. They also have been tested successfully in a JPL thermal vacuum chamber, with total vacuum conditions and temperatures of minus 76 degrees Fahrenheit (minus 60 degrees Celsius) to simulate the conditions of space. While Parness was in graduate school at Stanford University in Palo Alto, California, the grippers were tested separately in more than 30,000 cycles of "on" and "off," with the adhesive staying strong. Several prototypes have since been designed.

There are more than 21,000 pieces of orbital debris larger than 3.9 inches (10 centimeters) in Earth's orbit. The U.S. Space Surveillance Network routinely tracks these objects. In 2009, an accidental collision occurred between an operational communications satellite and a large piece of debris, destroying the satellite.

Besides grappling orbital debris, the grippers could help inspect spacecraft or assist small satellites in docking to the International Space Station. The grippers are another example of how technology drives exploration.

The California Institute of Technology manages JPL for NASA.

Source: NASA/Jet Propulsion Laboratory

How and When disaster strikes: Safeguarding networks

Safeguarding networks

Disasters both natural and human-caused can damage or destroy data and communications networks. Several presentations at the 2014 OFC Conference and Exposition, being held March 9-13 in San Francisco, Calif., USA will present new information on strategies that can mitigate the impacts of these disasters.

New Algorithm Finds Safe Refuge for Cloud Data
Much of our computing these days, from browsing websites and watching online videos to checking email and following social networks, relies on the cloud. The cloud lives in data centers -- massive warehouses filled with thousands of servers that run constantly. Disasters such as earthquakes, tornadoes, or even terrorist attacks, can damage the data centers and the communication links between them, causing massive losses in data and costly disruptions.

To mitigate such potential damage, researchers from the University of California, Davis (UC Davis), Sakarya University in Turkey, and Politecnico de Milano in Italy, first analyzed the risk that a disaster may pose to a communications network, based on the possible damage of a data center or the links that connect them to users. Then, they created an algorithm that keeps data safe by moving or copying the data from data centers in peril to more secure locations away from the disaster. The algorithm assesses the risks for damage and users' demands on the network to determine, in real-time, which locations would provide the safest refuge from a disaster.

"Our content placement solution can be implemented with some modifications on any existing settings of data centers and it is adaptable to different dynamic disaster scenarios," said researcher Sifat Ferdousi of UC Davis. "This can highly benefit the network providers in designing disaster-resilient cloud networks."

Integrating Wireless with Fiber for Temporary Emergency Networks
Earthquakes, tsunamis, and other natural disasters can sever the optical fibers that carry data across long distances, leaving telecommunications networks useless. If fiber-optic cables are down, wireless communication can fill the void and be part of a temporary, emergency network. But for such a system to work, wireless technology would have to be integrated with the fiber-optic network that transports data around the world.

Such an integrated wireless optical system would combine the speed and bandwidth of fiber optics with the mobility and range of a wireless network. This system could also be applied in home networks, in which data is sent via optical cables to the home then broadcasted wirelessly.

One big challenge of an integrated system, however, is to develop the wireless links that can handle the speed and capacity of optical cables. Researchers from Fudan University in Shanghai and ZTE (TX), Inc. in Morristown, N.J., USA have now developed a new antenna architecture that allows for a simple and high-speed integrated wireless optical system. The design relies on two pairs of antennas, explains Jianjun Yu of ZTE. Because each pair is polarized differently and isolated, there's no interference between the two pairs, allowing for a simpler structure and a larger transmission capacity. The new system achieves a data-transmission rate of 146 gigabits per second (Gb/s), which is the highest bit-rate-per-channel in a wireless signal shown so far, Yu says.

Source: The Optical Society
Summary: Disasters both natural and human-caused can damage or destroy data and communications networks. New information on strategies that can mitigate the impacts of these disasters.