Electric Solar Wind Sail Could Power Future Space Travel In Solar System

Source:

http://www.sciencedaily.com/releases/2008/04/080415162612.htm

ScienceDaily (Apr. 17, 2008) — The electric solar wind sail developed at the Finnish Meteorological Institute two years ago has moved rapidly from invention towards implementation. Electric sail propulsion might have a large impact on space research and space travel throughout the solar system.

The electric solar wind sail developed by Dr. Pekka Janhunen might revolutionise travelling in space. The electric sail uses the solar wind as its thrust source and therefore needs no fuel or propellant. The solar wind is a continuous plasma stream emanating from the Sun. Changes in the properties of the solar wind cause auroral brightening and magnetic storms, among other things.
The main parts of the device are long metallic tethers and a solar-powered electron gun which keeps the tethers positively charged. The solar wind exerts a small but continuous thrust on the tethers and the spacecraft.
“We haven't encountered major problems in any of the technical fields thus far. This has already enabled us to start planning the first test mission,” says Dr. Pekka Janhunen. An important subgoal was reached when the Electronics Research Laboratory of the University of Helsinki managed to develop a method for constructing a multiline micrometeoroid-resistant tether out of very thin metal wires using ultrasonic welding. The newly developed technique allows the bonding together of thin metal wires in any geometry; thus, the method might also have spinoff applications outside the electric sail.
Electric Sail For Space Travel
The electric sail could enable faster and cheaper solar system exploration. It might also enable economic utilisation of asteroid resources for, e.g. producing rocket fuel in orbit.
“The electric sail might lower the cost of all space activities and thereby, for example, help making large solar power satellites a viable option for clean electricity production. Solar power satellites orbiting in the permanent sunshine of space could transmit electric power to Earth by microwaves without interruptions. Continuous power would be a major benefit compared to, e.g. ground-based solar power where storing the energy over night, cloudy weather and winter are tricky issues, especially here in the far North,” says Dr. Pekka Janhunen.
Component work for the electric sail was carried out at the University of Helsinki and in Germany, Sweden, Russia and Italy. The electric sail was invented as a by-product of basic research done at the Finnish Meteorological Institute on the interaction of the solar wind with planets and their atmospheres. Work on the electric sail in Finland is currently funded by the Academy of Finland and private foundations.
The first international electric sail meeting will be arranged at ESA ESTEC in Noordwijk, The Netherlands on May 19, 2008.
Adapted from materials provided by Finnish Meteorological Institute.

Fausto Intilla

www.oloscience.com

Cycling More Intelligently

Source:

http://www.sciencedaily.com/releases/2008/04/080411150945.htm

ScienceDaily (Apr. 16, 2008) — Cycling is fun – if you can find the right tread. But those who tire themselves out quickly lose the desire to conquer the world on two wheels. A remedy could soon be available in the form of adaptronic components which report inappropriate biomechanical stress.

Modern bicycles leave nothing to be desired. 21, 24, 27 gears! For many amateur cyclists, such luxury is too much of a good thing. They change gear too infrequently and too late, get out of breath and don’t enjoy the ride. At the Hannover Messe in Germany (April 21 through 25), Fraunhofer researchers are presenting a bicycle with an intelligent pedal crank that helps the biker to direct his strength into the pedals.
There are two piezo-sensors integrated in one of the pedal cranks of this bicycle. One function of the sensors is to measure the forces that propel the rider forwards and show him how ‘evenly’ he is pedaling. In the exhibited prototype, the registered data are transmitted wirelessly in real time to a PC – in practical use this would be a device such as a PDA or a cell phone.
The integrated-function pedal crank is a result of the InGuss project, whose goal is to manufacture ‘intelligent’ cast parts, by directly integrating sensors, actuators and electronic components in the parts while they are being cast. In this project, researchers at the Fraunhofer Institutes for Manufacturing Technology and Applied Materials Research IFAM, for Structural Durability and System Reliability LBF and for Integrated Circuits IIS are developing the manufacturing technology and the components to be integrated.
The special feature of the bicycle pedal crank is that the piezoceramic actuators, sensors and electronic components are integrated in the light metal components during casting. This is no easy task, for the high temperatures of over 700°C that prevail during casting can destroy the sensitive electronic and electromechanical components. “We protect the components with special insulating materials, and adapt the process accordingly to prevent them from being damaged,” says Christoph Pille of the IFAM in Bremen. This would make it possible for the first time ever to integrate components such as RFID transponders during casting in such a way that they could not be lost, enabling components to be tracked, identified and protected against product piracy.
Heiko Atzrodt of the LBF is certain that this pedal crank demonstrator is just one example out of many potential applications for the technology: “Integrated sensor and adaptronic functions are likely to make their way into numerous products before long – for instance, sensors in aircraft parts could report material fatigue before it is too late. Integrated actuators make it possible to actively influence vibrations, too.”
Adapted from materials provided by Fraunhofer-Gesellschaft.

Fausto Intilla - www.oloscience.com

Road Safety: The Uncrashable Car?

Source:

http://www.sciencedaily.com/releases/2008/04/080412175201.htm

ScienceDaily (Apr. 15, 2008) — The largest road safety research project ever launched in Europe will usher in a series of powerful road-safety systems for European cars. But, in the long term, its basic, experimental research could lead to a car that is virtually uncrashable.

A truck exits suddenly from a side road, directly into your lane only dozens of metres ahead. Suddenly, your car issues a warning, starts applying the brakes and attempts to take evasive action. Realising impact is unavoidable; in-car safety systems pre-tension the safety belts and arm the airbag, timing its release to the second before impact.
Such is the promise of the uncrashable car, coming to a dealer near you in the perhaps not-too-distant future. The system is part of the basic research undertaken by the largest research initiative into road safety ever undertaken in Europe.
PReVENT has a budget of over €50 million and 56 partners pursuing a broad, but highly complementary programme of research. A dozen sub-projects focus on specific road-safety issues, but all projects support and feed into each other in some way.
PReVENT is studying relatively cheap, even simple, technologies – such as parking sensors and existing satellite navigation – that can be retooled to enhance driver safety. But as part of its broad and deep approach to car safety, it is also diving into more experimental and medium- to long-term systems, innovations that could appear in five-to-ten years.
The uncrashable car is a theoretical construct that concerned a handful of PReVENT’s sub-projects. But it could become far more of a reality than anyone expected.
Of course, it is impossible to stop all car collisions, but the technology could be pushed to make it increasingly unlikely and mitigate crashes when they do occur.
For example, PReVENT project WILLWARN uses wireless communication with other vehicles to alert the driver about potentially dangerous situations ahead, while MAPS&ADAS reads sat-nav maps to track approaching hazards, like bends, dips or intersections. SASPENCE looks at safe driving distances and speed, while LATERALSAFE finally brings active sensing to the blind spot.
All have their role in the uncrashable car, as do many others within the broader project. But two projects, APALACI and COMPOSE, take this a step further, actively tracking the speed and trajectories of surrounding vehicles and other road users in real time. If one vehicle suddenly stops, or a pedestrian suddenly steps onto the road, they swing into action to rapidly calculate the implications.
Predictive collision detection
APALACI is an advanced pre-crash mitigation system built round the registration of other motorists and cyclists. In the APALACI system, sensors monitor the street or road immediately around the vehicle and collect as much information about a collision as possible, before it even starts to take place.
The system uses this data to decide on the ideal safety reaction strategy. Examples include controlled braking manoeuvres, controlled activation of the occupant restraint systems or pre-arming airbag systems. The car can react far faster than the driver, cutting speed by crucial amounts to ensure unavoidable accidents are less severe.
APALACI also developed a so-called ‘Start Inhibit System’ for trucks. It surveys the blind spot immediately in front of a truck and protects pedestrians or cyclists by preventing dangerous manoeuvres.
APALACI was tested in a series of vehicles like the Fiat Stilo, the Volvo FH12 truck, the Alfa Romeo 156 and Mercedes E350. It used laser sensors, radar, software decision assistance and a variety of other technologies to achieve the goal.
Tiny changes have a huge impact
COMPOSE, on the other hand, aims more specifically to keep others, as well as its driver, safe. It can apply the brakes if a pedestrian steps onto the road, or extend the bumper, and raise the bonnet to enhance occupant protection.
Tiny differences have a huge impact on car safety. Dropping speed by 1km/h can reduce accidents with injury by 3 per cent, while braking fractions of a second sooner is enough to reduce the damage caused dramatically.
The systems were tested in the BMW 545i and the Volvo FH12 truck, and they do appreciably enhance safety. But, for all their potential, these systems remain, for now, the preserve of the future.
“The teams developed sophisticated algorithms to track all these elements in the landscape,” explains Matthias Schulze, coordinator of the EU-funded PReVENT project and Senior Manager for ITS & Services at Daimler AG. “But they require enormous computer power to keep track of all the various elements, so this work is aimed at basic research, establishing how it could be done. It will be a while before in-car computers are sophisticated enough to use these systems.”
Nonetheless, they do provide tools that automakers can use to mitigate the potential for accidents, and they provide a clear research roadmap for the uncrashable car of the future.
Adapted from materials provided by ICT Results.

Fausto Intilla

www.oloscience.com

Car Prototype Generates Electricity, And Cash

Source:

http://www.sciencedaily.com/releases/2007/12/071203133532.htm

ScienceDaily (Dec. 9, 2007) — The price of oil nearly reached $100 a barrel recently, but a new University of Delaware prototype vehicle demonstrates how the cost of the black stuff could become a concern of the past.

A team of UD faculty has created a system that enables vehicles to not only run on electricity alone, but also to generate revenue by storing and providing electricity for utilities. The technology--known as V2G, for vehicle-to-grid--lets electricity flow from the car’s battery to power lines and back.
“When I get home, I’ll charge up and then switch into V2G mode,” said Willett Kempton, UD associate professor of marine policy and a V2G pioneer who began developing the technology more than a decade ago and who is now testing the new prototype vehicle. The UD V2G team includes Kempton as well as Ajay Prasad, professor of mechanical engineering; Suresh Advani, George W. Laird Professor of Mechanical Engineering; and Meryl Gardner, associate professor of business administration, along with several students.
When the car is in the V2G setting, the battery’s charge goes up or down depending on the needs of the grid operator, which sometimes must store surplus power and other times requires extra power to respond to surges in usage. The ability of the V2G car’s battery to act like a sponge provides a solution for utilities, which pay millions to generating stations that help balance the grid. Kempton estimates the value for utilities could be up to $4,000 a year for the service, part of which could be paid to drivers.
The technology will work on a large scale, he said, because on average 95 percent of all cars are parked at any given time. One hour a day of car usage is the average in America.
“A car sitting there with a tank of gasoline in it, that’s useless,” he said. “If it’s a battery storing a lot of electricity and a big plug that allows moving power back and forth quickly, then it’s valuable.”
Kempton already has one of those large plugs at his home. He has a 240-volt plug that gives the battery a full charge--or a range up to 150 highway miles--in just two hours. A smaller, standard 110-volt plug works but provides a full charge in about 12 hours. The smaller plug also moves less power for the grid operator when the car is in V2G mode, Kempton explained.
“The bigger the plug, the more power you can move, the more revenue,” he said, explaining that it cost about $600 to have the larger plug installed.
But even though Kempton is supplying power to the grid with the prototype car, he’s not getting paid for it--yet.
PJM, the grid operator for 14 states, including Delaware, is keen on the technology and hosted a demonstration of the V2G car. But PJM requires at least 300 megawatts to purchase power. That means the UD team and its collaborators must get 300 cars up and running.
The prototype car is a stepping-stone to that goal. Kempton is working with UD mechanical engineers Prasad and Advani, who plan to add V2G to the University’s hydrogen fuel cell bus. Next, the team, including the company that created the car, California-based AC Propulsion, will test the prototypes and fix any potential problems they bring to light. Then they’ll begin creating a user interface that will let drivers, for example, tell the car to never go below 50 percent charge while in V2G mode.
Helping him to learn what types of features potential buyers would want on the car and to identify potential buyers are business administration faculty member Gardner and her students. They’ve done a pilot survey of nearly 100 drivers that’s shown there’s a lot of interest in the technology, she said.
“We also want to provide information on how to market the car,” she said, so her team is asking people questions like how much they would be willing to pay for it and how they feel about driving a car that’s better for the environment than a gasoline-powered vehicle.
That last question gets Kempton, who also is involved in College of Marine and Earth Studies research on offshore wind farms, the most excited. He explained that even if the electricity used to charge the car is produced by a coal-fired power plant, the car itself produces no carbon dioxide emissions. If a wind farm fuels the electricity from the power plant, he explained, the car and its power source would be emissions free.
And even though the green aspect of the car is key for Kempton, he knows consumers might have some other, more practical, questions about the vehicle, such as, “What’s it like to drive?”
Zippy yet quiet, being behind its wheel is a thrill, he said. “I hate getting back in my gas car. It feels sluggish.”
V2G prototype specifications
The Car: Manufactured by vehicle technology company AC Propulsion; formerly a Toyota Scion, which was chosen because it is light yet provides plenty of passenger room
Emissions: The car itself produces no carbon dioxide emissions
Acceleration: 0 to 60 miles per hour in 7 seconds
Top Speed: 95 miles per hour
Range: 120 highway, 150 city
Battery Life: 5 years or about 50,000 miles (being tested and verified)
Recharge: 2 hours using 240-volt plug or overnight using 110-volt plug
Maintenance: No oil changes; brakes last three times longer because the car has regenerative braking, a mechanism that slows the car and returns power to the battery
Adapted from materials provided by University of Delaware.

Fausto Intilla

www.oloscience.com

Wireless Sensors To Monitor Bearings In Jet Engines Developed

Source:

http://www.sciencedaily.com/releases/2007/10/071030160933.htm

ScienceDaily (Nov. 5, 2007) — Researchers at Purdue University, working with the U.S. Air Force, have developed tiny wireless sensors resilient enough to survive the harsh conditions inside jet engines to detect when critical bearings are close to failing and prevent breakdowns.

The devices are an example of an emerging technology known as "micro electromechanical systems," or MEMS, which are machines that combine electronic and mechanical components on a microscopic scale.
"The MEMS technology is critical because it needs to be small enough that it doesn't interfere with the performance of the bearing itself," said Farshid Sadeghi, a professor of mechanical engineering. "And the other issue is that it needs to be able to withstand extreme heat."
The engine bearings must function amid temperatures of about 300 degrees Celsius, or 572 degrees Fahrenheit.
The researchers have shown that the new sensors can detect impending temperature-induced bearing failure significantly earlier than conventional sensors.
"This kind of advance warning is critical so that you can shut down the engine before it fails," said Dimitrios Peroulis, an assistant professor of electrical and computer engineering.
Findings will be detailed in a research paper to be presented on Tuesday (Oct. 30) during the IEEE Sensors 2007 conference in Atlanta, sponsored by the Institute of Electrical and Electronics Engineers. The paper was written by electrical and computer engineering graduate student Andrew Kovacs, Peroulis and Sadeghi.
The sensors could be in use in a few years in military aircraft such as fighter jets and helicopters. The technology also has potential applications in commercial products, including aircraft and cars.
"Anything that has an engine could benefit through MEMS sensors by keeping track of vital bearings," Peroulis said. "This is going to be the first time that a MEMS component will be made to work in such a harsh environment. It is high temperature, messy, oil is everywhere, and you have high rotational speeds, which subject hardware to extreme stresses."
The work is an extension of Sadeghi's previous research aimed at developing electronic sensors to measure the temperature inside critical bearings in communications satellites.
"This is a major issue for aerospace applications, including bearings in satellite attitude control wheels to keep the satellites in position," Sadeghi said.
The wheels are supported by two bearings. If mission controllers knew the bearings were going bad on a specific unit, they could turn it off and switch to a backup.
"What happens, however, is that you don't get any indication of a bearing's imminent failure, and all of a sudden the gyro stops, causing the satellite to shoot out of orbit," Sadeghi said. "It can take a lot of effort and fuel to try to bring it back to the proper orbit, and many times these efforts fail."
The Purdue researchers received a grant from the U.S. Air Force in 2006 to extend the work for high-temperature applications in jet engines.
"Current sensor technology can withstand temperatures of up to about 210 degrees Celsius, and the military wants to extend that to about 300 degrees Celsius," Sadeghi said. "At the same time, we will need to further miniaturize the size."
The new MEMS sensors provide early detection of impending failure by directly monitoring the temperature of engine bearings, whereas conventional sensors work indirectly by monitoring the temperature of engine oil, yielding less specific data.
The MEMS devices will not require batteries and will transmit temperature data wirelessly.
"This type of system uses a method we call telemetry because the devices transmit signals without wires, and we power the circuitry remotely, eliminating the need for batteries, which do not perform well in high temperatures," Peroulis said.
Power will be provided using a technique called inductive coupling, which uses coils of wire to generate current.
"The major innovation will be the miniaturization and design of the MEMS device, allowing us to install it without disturbing the bearing itself," Peroulis said.
Data from the onboard devices will not only indicate whether a bearing is about to fail but also how long it is likely to last before it fails, Peroulis said.
The research is based at the Birck Nanotechnology Center in Purdue's Discovery Park and at Sadeghi's mechanical engineering laboratory.
Adapted from materials provided by Purdue University.

Fausto Intilla

www.oloscience.com

Acoustic Sensor Being Developed In New Anechoic Chamber

Source:

http://www.sciencedaily.com/releases/2007/10/071030103916.htm

ScienceDaily (Nov. 4, 2007) — The University of Alabama College of Engineering is developing a new acoustic sensor to be tested in UA’s new hemi-anechoic chamber. This new sensor could one day be used to help locate individuals trapped in collapsed buildings, such as after natural or man-made disasters.

Typically, multiple microphones are used to measure the location of an acoustic source, but this project is aimed at developing a single sensor that performs the same task. Its applications will be useful in aiding the military, homeland security and emergency rescue efforts.
“It’s exciting to work on a project that could dramatically change the effectiveness of emergency response teams,” said Dr. Steve Shepard, associate professor in mechanical engineering. “For instance, if a building collapses, our sensor could locate the noises made by victims trapped under debris and help rescue those victims more quickly. The sensor could also be used for security purposes, such as monitoring the location and motion of vehicles.”
Once a prototype is developed, the sensor will be tested in UA’s new hemi-anechoic chamber, which is one of the largest in the Southeast. The chamber is a room that is isolated from external sounds. The walls and ceiling are covered with a very-thick, foam-like material that eliminates all acoustic reflections. Shepard stated that being in the chamber is, “like standing in a very large quiet field. You can almost hear your own heartbeat.” This isolation allows for detailed acoustic measurements on a wide range of structures.
Visually, the chamber resembles a high-tech recording studio. The chamber walls are covered by 2-foot thick, gray, triangular-shaped foam wedges. The 8-inch thick metal walls are filled with insulation made from recycled denim material. Additionally, the entire chamber and the supporting concrete floor, all 150,000 pounds, float on springs to prevent outside vibrations from interfering with acoustic testing. The entire chamber is located in the AIME Building, which has 18-inch thick exterior concrete walls, another sound barrier.
“This chamber gives UA unique acoustic testing capabilities that most research organizations simply don’t have,” said Shepard. “This is true particularly when it comes to testing large machines, structures, and even automobiles. We can now take acoustic measurements on a machine and not worry about the effects of reflections or outside noise. Our ability to better understand how that machine radiates noise – and develop ways to make it quieter – has been greatly extended.”
Shepard said there are several areas researchers hope to explore, including:
reducing noise through powered systems and soundproofing
health monitoring of machines
heating and air conditioning system components
Gear, bearings, motor and engine noise
Consumer product noise and vibration
Shepard was awarded the $120,000 grant from the National Science Foundation to develop the new sensor. UA’s College of Engineering is partnering with Tuskegee University, where researchers received an additional $100,000 grant for their contribution to this research project. Throughout the project, UA and Tuskegee faculty and students will have an opportunity to use the chamber to evaluate prototypes for the acoustic sensor.
Adapted from materials provided by University of Alabama.

Fausto Intilla

www.oloscience.com

New Wireless Bridge Sensors Powered By Passing Traffic

Source:

http://www.sciencedaily.com/releases/2007/10/071019175317.htm

ScienceDaily (Oct. 22, 2007) — Clarkson University researchers have developed technology that uses the vibrations caused by passing traffic to power wireless bridge monitoring sensors.

Wireless battery-powered sensors that monitor bridges and report changes that may lead to failure are easy to install, but it is unwieldy to provide power for the sensors. Each bridge needs at least several sensors, many installed in hard-to-access locations. Replacing millions of batteries could become a problem, adding to the expense of maintaining the bridges. The Clarkson researchers have found a way around this problem.
"We have completely eliminated the battery from the equation," says Assistant Professor Edward S. Sazonov, who developed the technology along with Professor Pragasen Pillay. "Hermetically sealed wireless sensors powered by bridge vibration can remain on the bridge without need of maintenance for decades, providing continuous monitoring of such parameters as ice conditions, traffic flows and health status."
The two electrical and computer engineering professors, along with graduate students Darrell Curry and Haodong Li, used the New York State Route 11 bridge, a steel girder structure, which runs over the Raquette River in Potsdam, N.Y., as a case study.
Energy was harvested by locating an electromagnetic generator on a girder. The harvester responded to one of the natural vibration frequencies of the bridge. Each time a car or a truck passed over the bridge, even in a different lane from the sensor installation, the whole structure vibrated and excited the mover in the generator, producing electrical energy. Harvested electrical energy powered unique wireless sensors that increased energy output of the harvester and consumed only microwatts of power while performing useful tasks.
Sazonov and Pillay have been invited to present their work at the Transportation Research Board of the National Academies Meeting in Washington, D.C., in January. The board provides support for their research.
They are also working on using the energy harvesting technology to power the various sensors in passenger cars.
Wireless monitoring of bridges and overpasses has gained much attention in the past few years. Bridge collapses happen suddenly and unpredictably, often leading to tragic loss of human life. In 2006, the Federal Highway Administration listed 25.8 percent of the nation\'s 596,842 bridges as either structurally deficient or functionally obsolete. While many of these bridges will remain in service for years, they need monitoring and rehabilitation. Currently, bridge monitoring is performed through periodic visual inspections. In the tragic example of I-35W Mississippi River bridge collapse, the bridge passed a visual inspection a year prior to failure.
Adapted from materials provided by Clarkson University.

Fausto Intilla

www.oloscience.com