Hydrogen Technology Steams Ahead

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ScienceDaily (July 17, 2009) — Could the cars and laptops of the future be fuelled by old chip fat? Engineers at the University of Leeds believe so, and are developing an energy efficient, environmentally-friendly hydrogen production system. The system enables hydrogen to be extracted from waste materials, such as vegetable oil and the glycerol by-product of bio-diesel. The aim is to create the high purity hydrogen-based fuel necessary not only for large-scale power production, but also for smaller portable fuel cells.

Dr Valerie Dupont from the School of Process, Environmental and Materials Engineering (SPEME) says: “I can foresee a time when the processes we are investigating could help ensure that hydrogen is a mainstream fuel.
“We are investigating the feasibility of creating a uniquely energy efficient method of hydrogen production which uses air rather than burners to heat the raw product. Our current research will improve the sustainability of this process and reduce its carbon emissions.”
A grant of over £400k has been awarded to the University by the Engineering and Physical Sciences Research Council (EPSRC) within a consortium of 12 institutions known as SUPERGEN Sustainable Hydrogen Delivery.
Hydrogen is widely considered to be a potential replacement for fossil fuels, but it is costly to extract. There are also often high levels of greenhouse gases emitted during conventional methods of production.
The system being developed at Leeds – known as Unmixed and Sorption-Enhanced Steam Reforming - mixes waste products with steam to release hydrogen and is potentially cheaper, cleaner and more energy efficient.
A hydrocarbon-based fuel from plant or waste sources is mixed with steam in a catalytic reactor, generating hydrogen and carbon dioxide along with excess water. The water is then easily condensed by cooling and the carbon dioxide is removed in-situ by a solid sorbent material.
Dr Dupont says: “It’s becoming increasingly necessary for scientists devising new technologies to limit the amount of carbon dioxide they release. This project takes us one step closer to these goals – once we have technologies that enable us to produce hydrogen sustainably, the infrastructure to support its use will grow.”
“We firmly believe that these advanced steam reforming processes have great potential for helping to build the hydrogen economy. Our primary focus now is to ensure the materials we rely on - both to catalyse the desired reaction and to capture the carbon dioxide – can be used over and over again without losing their efficacy.”
Adapted from materials provided by University of Leeds.

Blind Can Take Wheel With Newly Designed Vehicle

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ScienceDaily (July 15, 2009) — A student team in the Virginia Tech College of Engineering is providing the blind with an opportunity many never thought possible: The opportunity to drive.

A retrofitted four-wheel dirt buggy developed by the Blind Driver Challenge team (http://www.me.vt.edu/blinddriver/) from Virginia Tech's Robotics and Mechanisms Laboratory uses laser range finders, an instant voice command interface and a host of other innovative, cutting-edge technology to guide blind drivers as they steer, brake, and accelerate. Although in the early testing stage, the National Federation of the Blind -- which spurred the project -- considers the vehicle a major breakthrough for independent living of the visually impaired.
"It was great!" said Wes Majerus, of Baltimore, the first blind person to drive the buggy on a closed course at the Virginia Tech campus this summer. Majerus is an access technology specialist with the National Federation of the Blind's Jernigan Institute in Baltimore, a research and training institute dedicated to developing technologies and services to help the blind achieve independence.
Majerus called his drive a liberating experience, adding that he drove before on Nebraska farm roads with his father as a guide in the passenger seat.
Sitting inside the vehicle, a blind driver can turn the steering wheel, stop and accelerate by following data from a computing unit that uses sensory information from the laser range finder serving as the 'eyes' of the driver, in addition to a combination of voice commands and a vibrating vest as guides. A member of the Virginia Tech student team sat next to Majerus in the passenger seat to monitor the system's software operations.
"It's a great first step," Majerus added. "As far as the differences between human instructions and those given by the voice in the Blind Driver Challenge car, the car's instructions are very precise. You use the technology to act on the environment -- the driving course -- in a very orderly manner. In some cases, the human passenger will be vague, "turn left" -- does that mean just a small turn to the left, or are we going for large amounts of turn?"
Also driving the vehicle was Mark Riccobono, also of Baltimore, the executive director of the Jernigan Institute, who also is blind. He called his test drive historic. "This is sort of our going to the moon project," he said
In 2004 Jernigan Institute challenged university research teams to develop a vehicle that would one day allow the blind to drive. Virginia Tech was the only university in the nation to accept the nonprofit's call two years later, said Dennis Hong, director of the Robotics and Mechanisms Laboratory, part of the Virginia Tech mechanical engineering department. The National Federation of the Blind provided a $3,000 grant to launch the project.
"I thought it would be a very rewarding project, helping the blind," said Hong, the current faculty adviser on the project. "We are not only excited about the vehicle itself, but more than that, we are excited about the potential of the many spin-off technologies from this project that can be used for helping the blind in so many ways."
The team will bring the Blind Driver Challenge vehicle to the National Federation of the Blind's Youth Slam summer camp event held July 26 through Aug. 1 in College Park, Md. There, the team hopes to have teenagers who would be obtaining their driver's licenses, but cannot because of their blindness, drive the buggy.
Youth participants also are expected to remote control drive miniature cars. Additionally, the car is expected to ride in a National Federation of the Blind-sponsored parade in Washington D.C.
"I most look forward to learning as much as I can from these bright young students," said Greg Jannaman, who led the Virginia Tech student team in his senior year and graduated in May with a bachelor's degree in mechanical engineering. "Blind students from across the nation apply to be selected to attend this summer camp. While we are there to provide an educational experience for them, I can only imagine the invaluable feedback and fresh new ideas that they will provide in return."
Jannaman is excited about the vehicle's success. "There wasn't a moment's hesitation with any of our blind drivers, whereas blind-folded sighted drivers weren't as quick to let go of their preconceptions," said Jannaman of Hendersonville, Tenn. "The blind drivers actually performed better than their sighted counterparts. An overwhelming sense of accomplishment overcame me as I simply rode along while Wes and Mark successfully navigated the driving course without my assistance."
Early models of the Blind Driver Challenge vehicle relied more on technologies for fully autonomous vehicles, previously developed by Virginia Tech mechanical engineering students as part of the DARPA Urban Challenge (http://www.vt.edu/spotlight/achievement/2007-10-29_victortango/2007-10-29-victortango.html). The student team redesigned the vehicle so that the blind motorist has complete control of the driving process, as any sighted driver would.
This change in approach led to new challenges, including how to effectively convey the high bandwidth of information from the laser sensors scanning the vehicle's surrounding environment to the driver fast enough and accurate enough to allow safe driving. As a result, the team developed non-visual interface technologies, including a vibrating vest for feedback on speed, a click counter steering wheel with audio cues, spoken commands for directional feedback, and a unique tactile map interface that utilizes compressed air to provide information about the road and obstacles surrounding the vehicle.
Riccobono knows of mock ups and non-working "blind driver car" set-ups from the past, but says this is the first working vehicle to put the blind and visually impaired in control of the steering wheel. "Blind people have brains, the capacity to make decisions," he said. "Blind people want to live independent lives, why would they not want to drive?"
Even once the technology is perfected, laws now barring the blind from driving and public perception must be changed, Riccobono said. "This is the piece that we know will be the most difficult," said Riccobono, adding that the car must be near-perfected before the National Federation of the Blind can truly push the car to law-makers and the general public. He said this effort will take millions of dollars in development.
The 2009-10 student team already is planning major changes to the technology, including replacing the dirt buggy vehicle with a fully electric car commonly used by traffic officers in downtown city centers. The all-electric vehicle would reduce the vibration which can cause problems to the laser sensor, and it will provide clean electric power for the computing units and that is better for the environment.
Hong is a National Science Foundation CAREER Award recipient. He received his bachelor's degree in mechanical engineering from the University of Wisconsin-Madison in 1994, and his master's and doctoral degrees in mechanical engineering from Purdue University in 1999 and 2002, respectively.
Adapted from materials provided by Virginia Tech.

Physics Of Bumpy Roads: What Makes Roads Ripple Like A Washboard?

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ScienceDaily (July 9, 2009) — Just about any road with a loose surface — sand or gravel or snow — develops ripples that make driving a very shaky experience. A team of physicists from Canada, France and the United Kingdom have recreated this "washboard" phenomenon in the lab with surprising results: ripples appear even when the springy suspension of the car and the rolling shape of the wheel are eliminated. The discovery may smooth the way to designing improved suspension systems that eliminate the bumpy ride.

"The hopping of the wheel over the ripples turns out to be mathematically similar to skipping a stone over water," says University of Toronto physicist, Stephen Morris, a member of the research team.
"To understand the washboard road effect, we tried to find the simplest instance of it, he explains. We built lab experiments in which we replaced the wheel with a suspension rolling over a road with a simple inclined plow blade, without any spring or suspension, dragging over a bed of dry sand. Ripples appear when the plow moves above a certain threshold speed."
"We analyzed this threshold speed theoretically and found a connection to the physics of stone skipping. A skipping stone needs to go above a specific speed in order to develop enough force to be thrown off the surface of the water. A washboarding plow is quite similar; the main difference is that the sandy surface "remembers" its shape on later passes of the blade, amplifying the effect."
Washboard road is familiar to drivers of back country roads the world over but also appears in some other surprising places in nature and technology. Just about any time a malleable surface is acted upon by a sideways force, you will get ripples. Washboard road is analogous to the little ripples that form on wind- or water-driven sand at the beach, and to the moguls which develop on ski hills. Motocross bikes and snowmobiles also make ripples. Washboard can also cause tiny bumps on steel railway tracks and even the read head in a hard disk can sometimes hop along the surface of the disk to make a washboard pattern.
In addition to Morris, the research collaboration includes lead author Anne-Florence Bitbol and Nicolas Taberlet of Ecole Normale Superieure in Lyon and Jim McElwaine of the University of Cambridge. Experiments were done in Cambridge and Lyon and results published in Physical Review E on June 26, 2009.
Adapted from materials provided by University of Toronto.