'Smart material' chin strap harvests energy from chewing

 

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This is the experimental set up of an energy harvesting chin strap.

A chin strap that can harvest energy from jaw movements has been created by a group of researchers in Canada.

It is hoped that the device can generate electricity from eating, chewing and talking, and power a number of small-scale implantable or wearable electronic devices, such as hearing aids, cochlear implants, electronic hearing protectors and communication devices.

The first results of the device's performance have been published today, 17 September, in IOP Publishing's journal Smart Materials and Structures.

Jaw movements have proved to be one of the most promising candidates for generating electricity from human body movements, with researchers estimating that an average of around 7 mW of power could be generated from chewing during meals alone.

To harvest this energy, the study's researchers, from Sonomax-ÉTS Industrial Research Chair in In-ear Technologies (CRITIAS) at École de technologie supérieure (ÉTS) in Montreal, Canada, created a chin strap made from piezoelectric fiber composites (PFC).

PFC is a type of piezoelectric smart material that consists of integrated electrodes and an adhesive polymer matrix. The material is able to produce an electric charge when it stretches and is subjected to mechanical stress.

In their study, the researchers created an energy harvesting chin strap made from a single layer of PFC and attached it to a pair of ear muffs using a pair of elastic side straps. To ensure maximum performance, the chin strap was fitted snugly to the user, so when the user's jaw moved it caused the strap to stretch.

To test the performance of the device, the subject was asked to chew gum for 60 seconds whilst wearing the head-mounted device; at the same time the researchers recorded a number of different parameters.

The maximum amount of power that could be harvested from the jaw movements was around 18 µW, but taking into account the optimum set-up for the head-mounted device, the power output was around 10 µW.

Co-author of the study Aidin Delnavaz said: "Given that the average power available from chewing is around 7 mW, we still have a long way to go before we perfect the performance of the device.

"The power level we achieved is hardly sufficient for powering electrical devices at the moment; however, we can multiply the power output by adding more PFC layers to the chin strap. For example, 20 PFC layers, with a total thickness of 6 mm, would be able to power a 200 µW intelligent hearing protector."

One additional motivation for pursuing this area of research is the desire to curb the current dependency on batteries, which are not only expensive to replace but also extremely damaging to the environment if they are not disposed of properly.

"The only expensive part of the energy harvesting device is the single PFC layer, which costs around $20. Considering the price and short lifetime of batteries, we estimate that a self-powered hearing protector based on the proposed chin strap energy harvesting device will start to pay back the investment after three years of use," continued Delnavaz.

"Additionally, the device could substantially decrease the environmental impact of batteries and bring more comfort to users.

"We will now look at ways to increase the number of piezoelectric elements in the chin strap to supply the power that small electronic devices demand, and also develop an appropriate power management circuit so that a tiny, rechargeable battery can be integrated into the device."

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Story Source:

The above story is based on materials provided by Institute of Physics. Note: Materials may be edited for content and length.

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Journal Reference:

1. Aidin Delnavaz, Jérémie Voix. Flexible piezoelectric energy harvesting from jaw movements. Smart Materials and Structures, 2014; 23 (10): 105020 DOI: 10.1088/0964-1726/23/10/105020

Global shift away from cars would save US$100 trillion, eliminate 1,700 megatons of carbon dioxide pollution

 

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The "High Shift" scenario for global transportation: slashing CO2 pollution, saving money, improving lives.

More than $100 trillion in cumulative public and private spending, and 1,700 megatons of annual carbon dioxide (CO₂) -- a 40 percent reduction of urban passenger transport emissions -- could be eliminated by 2050 if the world expands public transportation, walking and cycling in cities, according to a new report released by the University of California, Davis, and the Institute for Transportation and Development Policy (ITDP).

Further, an estimated 1.4 million early deaths could be avoided annually by 2050 if governments require the strongest vehicle pollution controls and ultralow-sulfur fuels, according to a related analysis of these urban vehicle activity pathways by the International Council on Clean Transportation (ICCT) included in the report.

"Transportation, driven by rapid growth in car use, has been the fastest growing source of CO₂ in the world, said Michael Replogle, ITDP's managing director for policy and co-author of the report. "An affordable but largely overlooked way to cut that pollution is to give people clean options to use public transportation, walking and cycling, expanding mobility options especially for the poor and curbing air pollution from traffic."

"The analysis shows that getting away from car-centric development will cut urban CO₂ dramatically and also reduce costs, especially in rapidly expanding economies," said report co-author Lew Fulton, co-director of NextSTEPS Program at the Institute of Transportation Studies at UC Davis. "It is also critical to reduce the energy use and carbon emissions of all vehicles."

The report, A Global High Shift Scenario, is the first study to examine how major changes in transport investments worldwide would affect urban passenger transport emissions as well as the mobility of different income groups. The authors calculated CO₂ emissions in 2050 under two scenarios, a business-as-usual scenario and a "High Shift" scenario where governments significantly increased rail and clean bus transport, especially Bus Rapid Transit (BRT), and helped urban areas provide infrastructure to ensure safe walking, bicycling and other active forms of transportation. The projections also include moving investments away from road construction, parking garages and other ways that encourage car ownership.

Under this High Shift, not only would CO₂ emissions plummet, but the net financial impact of this shift would be an enormous savings over the next 35 years, covering construction, operating, vehicle and fuel-related costs.

The report was released at the United Nations Habitat III Preparatory Meeting in New York on September 17th, in advance of the September 23rd United Nations Secretary-General's Climate Summit, where many nations and corporations will announce voluntary commitments to reduce greenhouse gas emissions, including new efforts focused on sustainable transportation.

"This timely study is a significant contribution to the evidence base showing that public transport should play central role in visions for the city of tomorrow" says Alain Flausch, Secretary General of the International Association of Public Transport, and member of UN Secretary General's Advisory Group on Sustainable Transport.

Better Mobility Leads to Social Mobility

The new report also describes sustainable transportation as a key factor in economic development. Under the High Shift scenario, mass transit access is projected to more than triple for the lowest income groups and more than double for the second lowest groups. Notably, the overall mobility evens out between income groups, providing those more impoverished with better access to employment and services that can improve their family livelihoods.

"Today and out to 2050, lower income groups will have limited access to cars in most countries under almost any scenario; improving access to modern, clean, high-capacity public transport is crucial," said Fulton.

"Unmanaged growth in motor vehicle use threatens to exacerbate growing income inequality and environmental ills, while more sustainable transport delivers access for all, reducing these ills. This report's findings should help support wider agreement on climate policy, where costs and equity of the cleanup burden between rich and poor are key issues," noted Replogle.

Emission Standards Save Lives

Air pollution is a leading cause of early death, responsible for more than 3.2 million early deaths annually. Exposure to vehicle tailpipe emissions is associated with increased risk of early death from cardiopulmonary disease and lung cancer, as well as respiratory infections in children. Car and diesel exhaust also increases the risk of non-fatal health outcomes, including asthma and cardiovascular disease.

The International Council on Clean Transportation evaluated the impacts of urban travel by cars, motorcycles, trucks and buses on the number of early deaths from exposure to soot emitted directly from vehicle tailpipes. "Future growth in vehicle activity could produce a four-fold increase in associated early deaths by 2050, even with a global shift to mass transit," said ICCT's Joshua Miller, a contributor to the study. "We could avoid about 1.4 million early deaths annually if national leaders committed to a global policy roadmap that requires the strongest vehicle pollution controls and ultralow-sulfur fuels." Cleaner buses alone would account for 20 percent of these benefits.

Fuel Economy Standards Save Fuel and Cut CO₂ Emissions

While this study has not focused on further actions to boost motor vehicle fuel economy, it takes into account existing policies that, in the International Energy Agency's Baseline scenario, improve average new car fuel economy by 32 percent in countries that belong to the Organisation for Economic Co-operation and Development (OECD), a group of 34 of the world's most developed, democratic, market economies, and 23 percent in non-OECD countries.

The High Shift scenario increases this to 36 percent and 27 percent respectively, due to improved in-use driving conditions and a slight shift to smaller vehicles. However, the Global Fuel Economy Initiative (GFEI) calls for much more: a 50 percent reduction in fuel use per kilometer for light-duty vehicles worldwide by 2030. Achieving the GFEI 2030 goal could reduce 700 megatons of CO₂ annually beyond the 1,700 reduction possible from a High Shift scenario. Taken together, achieving this fuel economy goal with better public transport, walking and cycling could cut annual urban passenger transport CO₂ emissions in 2050 by 55 percent from what they might otherwise be in 2050 and 10 percent below 2010 levels.

Cutting Emissions with Sustainable Transportation Across the World's Cities

Transportation in urban areas accounted for about 2,300 megatons of CO₂ in 2010, almost one quarter of carbon emissions from all parts of the transportation sector. Rapid urbanization -- especially in fast developing countries like China and India -- will cause these emissions to double by 2050 in the baseline scenario.

Among the countries examined in the study, three stand out:

• United States: Currently the world leader in urban passenger transportation CO₂ emissions, with nearly 670 megatons annually, the US is projected to lower these emissions to 560 megatons by 2050 because of slower population growth, higher fuel efficiencies, and a decline in driving per person that has already started as people move back to cities. But this pace can be sharply accelerated with more sustainable transportation options, dropping to about 280 megatons, under the High Shift scenario.
• China: CO₂ emissions from transportation are expected to mushroom from 190 megatons annually to more than 1,100 megatons, due in large part to the explosive growth of China's urban areas, the growing wealth of Chinese consumers, and their dependence on automobiles. But this increase can be slashed to 650 megatons under the High Shift scenario, in which cities develop extensive BRT and metro systems. The latest data show China is already sharply increasing investments in public transport.
• India: CO₂ emissions are projected to leap from about 70 megatons today to 540 megatons by 2050, also because of growing wealth and urban populations. But this increase can be moderated to only 350 megatons, under the High Shift scenario, by addressing crucial deficiencies in India's public transport.

Math model designed to replace invasive kidney biopsy for lupus patients

 

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Mathematics might be able to reduce the need for invasive biopsies in patients suffering kidney damage related to the autoimmune disease lupus.

In a new study, researchers developed a math model that can predict the progression from nephritis – kidney inflammation – to interstitial fibrosis, scarring in the kidney that current treatments cannot reverse. A kidney biopsy is the only existing way to reach a definitive diagnosis of the damage and its extent.

The model could also be used to monitor the effectiveness of experimental treatments for inflammation and fibrosis.

This fibrosis can follow development of lupus nephritis, which occurs in about 60 percent of lupus patients, according to the National Institutes of Health. Inflammation is linked to the most common type of lupus, called systemic lupus erythematosus. The cause of lupus is unknown and it cannot be cured.

The research is published this week in the online early edition of Proceedings of the National Academy of Sciences.

The math model comprises a series of equations that account for the complex inflammatory process leading from nephritis to fibrosis in damaged kidneys. As designed, the model can detect the extent of kidney damage and predict how inflammatory processes will react to different therapies.

“The most important use of this model will be improving the design of clinical trials for new medications to treat the kidneys before they develop fibrosis,” said lead author Avner Friedman, a Distinguished University Professor in The Ohio State University’s Department of Mathematics. “Establishing a dose of an experimental therapy is the most difficult part of testing new drugs. The model could give a starting point for an effective dose.”

Better management of kidney damage in lupus is an urgent medical need because patients with moderate or severe fibrosis are more likely to develop chronic or end-stage kidney disease, said Brad Rovin, professor and director of the division of nephrology at Ohio State’s Wexner Medical Center and a co-author of the paper.

“If a kidney is already damaged, we can’t expect to go back in frequently to extract more tissue for multiple biopsies,” Rovin said.

Modeling by mathematicians with expertise in biomedical processes has become increasingly important in the health sciences. The modeling reduces the need for guesswork and time-consuming animal testing traditionally required as researchers pursue prevention, diagnosis and treatment of complex diseases. And in this case, math modeling would replace an invasive diagnostic test.

Lupus is an autoimmune disorder, meaning the immune system attacks healthy cells and tissue in the body. Lupus commonly affects the kidneys, where immune cells accumulate in the organ’s filtering units. This triggers an out-of-control inflammatory process that eventually leads to scarring and degradation of structures called tubules, which collect filtered fluid and are involved in the production of urine.

Further validation and refinement of the model is required, said Friedman, also founding director of the Mathematical Biosciences Institute (MBI) at Ohio State. But in this study, a comparison with human patient data showed that levels of inflammatory proteins in the urine of patients with mild, moderate or severe fibrosis matched levels predicted by the model.

The model also allows scientists to simulate the scarring injury and detect how the damage would respond to the therapies that target specific pathways to disease – either the inflammatory process or the scarring itself. By identifying vulnerabilities in the process from inflammation to scarring, the model could even point to the cells and proteins that would be the most promising treatment targets, Friedman said.

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Story Source:

The above story is based on materials provided by Ohio State University. The original article was written by Emily Caldwell. Note: Materials may be edited for content and length.

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Journal Reference:

1. W. Hao, B. H. Rovin, A. Friedman. Mathematical model of renal interstitial fibrosis. Proceedings of the National Academy of Sciences, 2014; DOI: 10.1073/pnas.1413970111

Engineers develop algorithms to switch out and recharge battery modules in electric cars

 

Rather than swapping out the whole battery, which is cumbersome and requires large, heavy equipment, engineers plan to swap out and recharge smaller units within the battery, known as modules. They named the project Modular Battery Exchange and Active Management, or M-BEAM for short.

Engineers have already purchased and converted a car, a 2002 four-door Volkswagen Golf. They also built all the modules for one of the two battery packs they plan to use and are now looking for sponsors for their project, including companies or individuals that appreciate the benefits of having small exchangeable battery modules in an electric vehicle.

"This is a game-changing technology," said Lou Shrinkle, an electrical engineer who is one of the major sponsors of the project. "This idea may seem straightforward, but there were some tough technical challenges that we had to solve to make this system robust and practical."

Swapping battery modules could also have far-reaching implications for mobile and decentralized electrical energy storage systems such as solar backup and portable generators. The technology can make energy storage more configurable, promote safety, simplify maintenance and eventually eliminate the use of fossil fuels for these applications, Shrinkle pointed out.

Engineers not only believe that their approach is viable, but also plan to prove it. They will embark on a cross-country trip with a car powered by the removable, rechargeable M-BEAM battery modules. They plan to drive from coast to coast only taking breaks that are a few minutes long to swap out the modules that will be recharged in a chase vehicle. They believe they can drive from San Diego to the coast of South Carolina less than 60 hours -- without going over the speed limit.

"This requires a completely different way of thinking on battery management," said Raymond de Callafon, a mechanical engineering professor at the Jacobs School of Engineering at UC San Diego. "Electric storage capacity is increased when modules are connected in parallel, but this requires a careful control of stray currents between modules."

Algorithms for charge estimation and current control

A team led by de Callafon is designing the algorithms for charge estimation and current control, implemented in an embedded system that is part of the battery management system for each module. The algorithms will be able to handle battery modules with different charge levels, chemistry, age and condition and keep the modules working together uniformly. The team has published their findings in a recent paper titled "Current Scheduling for Parallel Buck Regulated Battery Modules" in the IFAC World Congress held in Cape Town, South Africa in August, 2014.

Xin Zhao, the graduate student that is part of the team, explains in the paper that rechargeable, removable battery modules in electric cars would solve numerous problems. Being able to simply swap and combine battery modules would eliminate range anxiety and extend the range that cars are able to travel indefinitely -- the average range of most affordable electric vehicles is about 70 to 100 miles per charge. Batteries themselves take 4 to 12 hours to charge with conventional power sources. Newer, fast-charge technology still takes about 30 minutes and involves running very high power through batteries, shortening their lifetime and reducing safety.

What would change

The team says there are many advantages in their approach of recharging and swapping out smaller modules within a large battery. The approach allows for a separation between the purchase of an electric vehicle and its battery pack. The price of electric vehicles would drop by about $10,000 if removable battery modules are leased rather than built into an electric vehicle.

Also, as of today, more than 40 percent of people living in cities don't have access to wall outlets to charge their electrical vehicles at the curb or in a garage. Exchangeable modules could be taken out of the car and recharged at home. Exchangeable modules would also allow an expanded mix of chemistries and energy densities lowering costs and improving range. Removable batteries could even be brought into the home to be charged and be part of an electricity back-up system.

Challenges and future work

But there are challenges. At 20 to 30 lbs. each, the modules are not exactly light-weight. Researchers believe that as battery technology matures, module size will shrink to about the size of a tissue box, weighing less than 10 lbs. The ability to swap battery modules from an electric vehicle allows easy adaptation of such new battery technology.

A battery system based on exchangeable modules would also need an infrastructure that allows users to lease or purchase the rechargeable modules. Businesses that either charge the modules or rent out pre-charged modules would also need to be available throughout the country. But engineers point out that electric vehicle charging stations, especially fast-charge stations, are not widely available either. Exchange stations could easily be gradually deployed. Imagine simply exchanging your modules at the local gas station that charges them for you, much like you can fill up propane tanks today.

Electric shock can also be a risk during removal and replacement of high voltage modules. The battery management system developed by the research team ensures that the output voltage of the battery is equal to zero unless the battery is in the vehicle and enabled by a key switch. Modules are configured to exhibit only safe low voltages even when fully compromised during and after a crash and have built-in solid-state switches to handle a short circuit condition.

Professor de Callafon is excited about the design and testing of the battery modules using a cross-country trip with an electric vehicle. "The cross-country trip will generate a wealth of scientific data on the performance of the battery modules we have designed." The team hopes that the cross-country trip will change the way we think about mobile energy storage for electric transportation.

Nature's designs inspire research into new light-based technologies

 

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Understanding how particle scatter (above) and minerals (top) affect water color in pools at Yellowstone National Park may provide important information for the development of alternative fuels. Phenomena of light in nature such as this were the topic of a conference at SPIE Optics + Photonics, with results published in the SPIE Digital Library.

"Nature has developed, very cleverly, some lessons on how to create the features that we desire in optical design," said Joseph Shaw, director of the Optical Technology Center at Montana State University. "As we explore surfaces and structures at the nanoscale, we'll discover them."

Some of those lessons were presented in San Diego in August during a conference called "The Nature of Light: Light in Nature" chaired by Shaw and Rongguang Liang of the University of Arizona College of Optical Sciences. The conference was part of SPIE Optics + Photonics, sponsored by SPIE, the international society for optics and photonics.

The conference is particularly relevant as the optics and photonics community prepares for the United Nations International Year of Light 2015, Shaw said. "Such lessons from nature not only remind us of how light-based technologies touch all of our lives and help solve challenges in energy, healthcare, communications, and other areas, but they also remind us to pause and appreciate the visual beauty found throughout nature."

Shaw, whose research as a professor in electrical and computer engineering involves developing optical sensors for applications ranging from imaging of clouds to laser-detection of fish, said that observing how nature solves problems is particularly helpful for optical designers and engineers working with very small structures.

Insect wings that absorb all of the visible light spectrum and iridescent shells, for example, each possess optical surfaces that might find design applications one day, perhaps as camouflage.

Some wings have antireflective cone-like structures of a few nanometers that absorb virtually the entire visible spectrum, a team from the University of Namur (Louis Dellieu, et al.) reported. In the grey cicada, absorption is a product of the distinctive shape of tiny surface cones.

Iridescence of the lining of mollusk shells was explored by a team from Colgate University (R. A. Metzler, et al.), who reported on the polarization effects of the lining, known as nacre, or mother of pearl. It consists of up to 30,000 layers of tiny calcium carbonate "bricks" -- just 0.5 microns, or a 200th of the diameter of a human hair -- held together by a "mortar" of organic chitin. Reflected light from the lining produces the shells familiar array of colors.

"We have the tools for nanoengineering and nanoexploration," Shaw said. "We can do reverse engineering of the structures."

Color of vivid blue pools, some as hot as 250 degrees Fahrenheit, at Yellowstone National Park in Wyoming and Montana has only little to do with reflection of sky light, a paper by Shaw and others reported. The blue comes from the scatter of particles in the water. The deeper the water, the more dominant the scatter and the richer the blue. Red, orange, and yellow colors of other pools are driven by varieties of microbes on the rock surfaces under the water and related to the temperature of water in each pool.

Applications of these findings could include using a color imager to infer information about such pools and their resident microbe communities and what causes their presence. This could connect with NASA-funded research, because of the similarity of Yellowstone microbes with possible early forms of life on Earth and other planets. Ongoing Yellowstone research is even exploring how these microbes might inspire development of alternative fuels.

Optical labs looking for higher-efficiency solar cells or light-emitting diodes (LEDs) might one day use genetic algorithms to streamline their work. A team from Namur University of Namur (Alexandre Mayer, et al.), noting that thinking through a design question could mean millions or billions of options to check, demonstrated that a genetic algorithm can quickly make many small changes. A lab might need to explore only a few hundred options instead of millions. The genetic algorithm would work the way natural evolution does: scanning all the possibilities and quickly narrowing down the search.

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Story Source:

The above story is based on materials provided by SPIE. Note: Materials may be edited for content and length.

Reduce traffic congestion: Wirelessly route drivers around congested roadways

 

September 17, 2014

Massachusetts Institute of Technology

At the Intelligent Transportation Systems World Congress last week, MIT researchers received one of the best-paper awards for a new system, dubbed RoadRunner, that uses GPS-style turn-by-turn directions to route drivers around congested roadways. In simulations using data supplied by Singapore's Land Transit Authority, the researchers compared their system to one currently in use in Singapore, which charges drivers with dashboard-mounted transponders a toll for entering congested areas.

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At the Intelligent Transportation Systems World Congress last week, MIT researchers received one of the best-paper awards for a new system, dubbed RoadRunner, that uses GPS-style turn-by-turn directions to route drivers around congested roadways.

In simulations using data supplied by Singapore's Land Transit Authority, the researchers compared their system to one currently in use in Singapore, which charges drivers with dashboard-mounted transponders a toll for entering congested areas.

The Singapore system gauges drivers' locations with radio transmitters mounted on dozens of gantries scattered around the city, like the gantries used in many U.S. wireless toll systems. RoadRunner, by contrast, uses only handheld devices clipped to cars' dashboards. Nonetheless, in the simulations, it yielded an 8 percent increase in average car speed during periods of peak congestion.

Moreover, for purposes of comparison, the MIT researchers restricted themselves to road-access patterns dictated by Singapore's existing toll system. Modifying those patterns -- encouraging or discouraging the use of different stretches of road -- could, in principle, lead to even greater efficiency gains.

"With our system, you can draw a polygon on the map and say, 'I want this entire region to be controlled,'" says Jason Gao, a graduate student in electrical engineering and computer science who developed the new system together with his advisor, Professor of Electrical Engineering and Computer Science Li-Shiuan Peh. "You could do one thing for a month and test it out and then change it without having to dig up roads or rebuild gantries."

Gao and Peh also tested their system on 10 cars in Cambridge, Mass. Of course, 10 cars is not enough to dramatically affect local traffic patterns. But it was enough to evaluate the efficiency of the communications system and of the vehicle-routing algorithm. It also provided reliable data about the system's performance for use in simulations.

Max capacity

Urban toll systems like the one in Singapore designate certain regions -- with gantries at every entry point -- as prone to congestion. Drivers are charged a fee for entering any such region, so they have an incentive to avoid it. The fee fluctuates over the course of the day, according to historical traffic data.

RoadRunner, by contrast, assigns each such region a maximum number of cars. Any car entering the region must acquire a virtual authorization that Gao and Peh call a "token." If no tokens are free, RoadRunner routes the car around the region using turn-by-turn voice prompts.

The version of RoadRunner used in the Cambridge tests was largely decentralized: A car leaving a region would wirelessly announce that its token was available, and a car seeking to enter the region would request it. The system used a wireless standard called 802.11p, a variation on Wi-Fi that uses a narrower slice of the electromagnetic spectrum but is licensed for higher-power transmissions, so that it has a much larger broadcast range.

It could be that the time savings promised by RoadRunner would be enough to induce commuters to use it. But it would also be possible to modify the system so that any car entering a congestion-prone region without a token would be assessed a small fine.

Reporting a car for tokenless entry would require uploading data to a central server, but it wouldn't require specifying the car's location at a resolution finer than that of the region. So Gao believes that, even though RoadRunner relies on GPS data, it wouldn't compromise drivers' privacy any more than existing urban toll systems do. In fact, he argues, it would compromise privacy less, since cars that followed the system's routing instructions would never have their locations reported.

An app for that

In their experiments, Gao and Peh used cellphones to control commercial 802.11p radios, which are about the size of a typical electronic-toll dashboard transponder. But in the future, it may be possible to embed the radios directly into cellphones.

At the International Symposium on Low Power Electronics and Design in August, Gao, Peh, and lead author Pilsoon Choi, a postdoc in Peh's group, together with researchers at Nanyang Technological University in Singapore, presented a paper demonstrating that an 802.11p radio built from gallium nitride and controlled by silicon electronics would consume half the power that existing radios do.

Moreover, the Singapore-MIT Alliance for Research and Technology (SMART) has developed a technique for integrating gallium nitride into existing silicon-chip manufacturing processes and is currently building a chip-fabrication facility to implement it.

"In Singapore, the government already requires every single registered vehicle to have a dash-mounted transponder," Gao says. "That's already there, so you might as well take advantage of it. In other places, where you don't have that in place, it would be easier to deploy it if you said, 'You can download this app and just leave your cellphone on your dashboard.'"

"A distributed decision process is an alternative to centralized models that has to be explored and, as far as I know, has been rarely if not ever addressed," says Jean Bergounioux, secretary general of ATEC ITS France, a French industrial research consortium dedicated to novel transportation systems. "RoadRunner offers the possibility of decentralizing as many decisions as possible at the lower level, without excluding that global decisions be made at the upper level."

"It's worth getting into field trial as soon as possible to test and evaluate the feasibility of its industrial development and deployment," Bergounioux adds.

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Story Source:

The above story is based on materials provided by Massachusetts Institute of Technology. Note: Materials may be edited for content and length.