Team prints 'world's first' 3D titanium car components

UK researchers claim to have produced the world’s first 3D-printed titanium car parts, demonstrating how the metal could become cheap enough for commercial production.

Titanium is usually considered too expensive for use in automotive manufacturing but a novel process for producing titanium powder from sand has opened the way for 3D printing parts cheaply enough for low-to-medium volume production, according to engineers from Sheffield University.

The process, created by Rotherham-based company Metalysis (originally a spin-out of Cambridge University), creates titanium powder at much lower cost than the conventional method of atomising blocks of metal, said Prof Iain Todd, director of the university’s Mercury Centre in the department of materials.

This means automotive parts can be made more economically using additive manufacturing rather than traditional subtractive techniques that waste large amounts of the expensive metal and use costly die set tools, he told The Engineer. 

‘If you wanted to make anything out of titanium you normally wouldn’t bother because it’s not a commodity metal. But also the process is getting a lot quicker. It’s certainly a lot better for moderate runs - it used to be very low-volume production runs.’

Todd’s team has used the material to 3D print parts including impellers and turbochargers, as well as aerofoils, using a Renishaw laser additive manufacturing machine and standard operating procedures based on the material’s thermal characteristics.

‘It processes beautifully,’ he said. ‘It’s probably one of the easiest materials we’ve ever put on.’

The research doesn’t take titanium automotive printing to the point where the material or the technique could be commonly used for mass production. But Todd is confident things are moving towards that.

‘Each time we change something we move closer to the point where titanium could be considered like something as stainless steel,’ he said.

‘That’s still a high-value steel but you’re looking that costs the same, is about half the density and has temperature capabilities that are quite attractive I think you’re looking at an interesting competitor to standard automotive material.’

The researchers now plan to work with Metalysis to create other materials from the titanium powder, particularly alloys that would normally separate when formed from conventional titanium.

Source: http://www.theengineer.co.uk/channels/design-engineering/news/team-prints-worlds-first-3d-titanium-car-components/1017653.article#ixzz2n04oYTV0

Copenhagen Wheel Turns Any Bicycle Into Hybrid ‘e-bike’

MIT-spinoff Superpedestrian unveiled a commercial version of its Copenhagen Wheel on Tuesday, allowing consumers to turn any ordinary bicycle into a hybrid “e-bike.”

The $700 rear wheel works in a fashion similar to a Toyota Prius or Chevy Volt, converting and storing energy during pedaling, braking and descending that is later used to boost riders as they accelerate or go uphill.

The wheel’s onboard electronics detect how hard the rider is pedaling, and trigger the motor to automatically assist when needed.

“The Wheel learns about the rider and intuitively recognizes how hard he or she pedals and the topography ahead to determine how much support the rider may need,” Superpedestrian said in a statement obtained by CNET. “There aren’t any additional throttles, wires, or buttons, maintaining the pure simplicity of cycling.”

The amount of assistance the Copenhagen Wheel provides can also be predetermined by the rider using a smartphone app, which provides riders with data such as distance traveled, calories burned and elevation gain.

The wheel – a sleek-looking, 12-pound red disk that sits within the spokes of the bike’s back wheel – features either a 250-watt or 350-watt hub motor, a rechargeable lithium-ion battery, a range of approximately 30 miles (48 km) and a top assisted speed of 20 mph (32 km/h). It is available in 26-inch, 27-inch and 700C sizes.

Battery life is typically extended through a regenerative braking system, although the battery can be removed and recharged when required, Superpedestrian said.

MIT’s SENSEable City first unveiled the prototype of the Copenhagen Wheel back in 2009, but the production version is being made by Superpedestrian, a company comprised of SENSEable City team members who licensed the technology from MIT.

The wheel’s development was sponsored by the Mayor of Copenhagen, after which the wheel is named.

The Copenhagen Wheel is available for pre-order now through Superpedestrian’s website, although the handmade modules won’t begin shipping until the first quarter of 2014. The first 1,000 units are already in production, and will be available for mountain bike and road bike wheel sizes, the Boston-based startup said.

The $700 version of the wheel represents a single-gear configuration, with a multiple gear version available at additional cost.

Source: redOrbit.com

Sony's Smart Wig

As computer engineers continue to develop smaller and more adaptable technology, electronic devices are turning up in all kinds of places – from wristwatches to refrigerator doors.

In a step marking the latest evolution of this device culture, Sony has filed a patent with the US Patent & Trademark Office for a “Smart Wig” capable of functions such as giving driving directions, checking blood pressure or manipulating a slideshow presentation.

“The usage of a wig has several advantages that, compared to known wearable computing devices, include significantly increased user comfort and an improved handling of the wearable computing device,” the Sony patent said.

Filed in May — not made public until this week – the patent describes hidden input sensors in the wig that analyze data, communicate wirelessly and give tactile feedback. These sensors would be covered by parts of the wig and hidden from sight. According to the patent, the Smart Wig could be fashioned from horse hair, human hair, wool, feathers, yak hair, buffalo hair or synthetic materials.

The patent from the Japanese-based company also stated that the device has the potential to become “very popular” and could be a “technically intelligent item and fashion item at the same time.”

Sony said the device could be used for gaming applications or “any type of virtual reality appliance;” although it did not provide any specific examples.

While an actual product based on the patent may never come to market, Sony’s move continues the trend of developing wearable devices, a trend that has also been embraced by Google and Samsung.

“Wearable gadgets are definitely going to be one of the big areas of growth over the next two years,” Andrew Milroy, an analyst with consulting firm Frost & Sullivan, told the BBC. “And Sony – which is trying to regain some of the sheen it has lost in recent years – clearly understands that and wants to play a major role in the sector.”

“It’s an interesting idea but I think it would be very difficult for Sony to commercialize,” Mitsushige Akino, chief fund manager at the Japanese firm Ichiyoshi Asset Management Co., told Bloomberg News. “Who will want to use this wig will become a problem.”

Bloomberg also confirmed through a spokesperson that the device was conceived by Sony engineer Hiroaki Tobita.

“Smartwatches are already made by many companies, so this is something new and fun,” Junya Ayada, a Tokyo-based analyst at Daiwa Securities Group Inc., said in a phone interview with Bloomberg.

If Sony’s Smart Wig were to ever come to market, it would join other wearable devices from the company’s product line – such as its SmartWatch 2.

In October, the company’s CEO Kazuo Hirai told reporters that Sony was both developing new devices and studying consumer needs for wearable computers.

In a September interview with Bloomberg, Sony vice president Yasuhiro Ueda said the company is developing chips for products such as self-driving cars and medical devices. These chips are somewhat similar to those already being used for smartphones and digital cameras.

Source: redorbit.com

Wireless recharging on the move

Researchers have developed new technology and techniques for transmitting power wirelessly from a stationary source to a mobile receiver.

The research, conducted at North Carolina State University, could lead to so-called highway ‘stations’ that can recharge electric vehicles wirelessly as the vehicles drive by.

‘We’ve made changes to both the receiver and the transmitter in order to make wireless energy transfer safer and more efficient,’ said Dr Srdjan Lukic, an assistant professor of electrical engineering at NC State and senior author of a paper on the research.

The researchers developed a series of segmented transmitter coils, each of which broadcasts a low-level electromagnetic field. The researchers also created a receiver coil that is the same size as each of the transmitter coils, and which can be placed in a car or other mobile platform.

The researchers modified the receiver so that when it comes into range and couples with a transmitter coil, that specific transmitter coil automatically increases its current – boosting its magnetic field strength and the related transfer of energy by 400 per cent. The transmitter coil’s current returns to normal levels when the receiver passes out of the range of the transmitter.

These modifications are claimed to improve on previous mobile, wireless power transfer techniques.

One previous approach was to use large transmitter coils, but this approach created a powerful and imprecise field that could couple to the frame of a car or other metal objects passing through the field. Because of the magnetic field’s strength, which is required to transfer sufficient power to the receiver, these electromagnetic field ‘leaks’ raised safety concerns and reduced system efficiency.

Another previous approach used smaller transmitter coils, which addressed safety and efficiency concerns. But this approach would require a very large number of transmitters to effectively ‘cover’ a section of the roadway, adding substantial cost and complexity to the system, and requiring very precise vehicle position detection technology.

‘We tried to take the best from both of those approaches,’ Lukic said in a statement.

Lukic and his team have developed a small, functional prototype of their system, and are now working to both scale it up and increase the power of the system.

Currently, at peak efficiency, the new system can transmit energy at a rate of 0.5kW. ‘Our goal is to move from 0.5kW into the 50kW range,’ Lukic said. ‘That would make it more practical.’

The paper, ‘Reflexive Field Containment in Dynamic Inductive Power Transfer Systems,’ is published online in IEEE Transactions on Power Electronics.

Source: http://www.theengineer.co.uk/energy-and-environment/news/wireless-recharging-on-the-move/1017546.article#ixzz2lrEKfB8T

New Process Cuts 3D Print Time From Hours To Minutes

Researchers at the University of Southern California have developed a new 3D printing process, and are using it to model and fabricate heterogeneous objects comprised of multiple materials in minutes instead of hours.

3D printing has the potential to transform industries by providing faster, cheaper and more accurate manufacturing options. However, the lengthy fabrication times and complexity of multi-material objects have long been an obstacle to its widespread commercial use.

In the current work, USC Professor Yong Chen and his team were able to reduce the fabrication time to just minutes, bringing the manufacturing world one step closer to achieving its goal.

“Digital material design and fabrication enables controlled material distributions of multiple base materials in a product component for significantly improved design performance. Such fabrication capability opens up exciting new options that were previously impossible,” said Chen, professor in the Daniel J. Epstein Department of Industrial and Systems Engineering at USC and the study’s lead researcher.

Traditional modeling and prototyping approaches used to take days to complete. But over the past several decades various additive manufacturing (AM) processes have been developed to fabricate both homogeneous and heterogeneous objects more quickly. Existing AM processes such as multi-jet modeling, which creates a solid 3D object from a digital model by laying down successive layers of material, can fabricate a complex object in a matter of hours.

Last year, Chen and another team of USC researchers improved an AM-related process known as mask-image-projection-based stereolithography (MIP-SL) to dramatically accelerate the fabrication of homogeneous 3D objects. MIP-SL process begins with a 3D digital model of an object, which is then sliced by a set of horizontal planes. Each slice is then converted into a two-dimensional mask image, which is projected onto a photocurable liquid resin surface. Light is then projected onto the resin to cure it in the shape of the related layer.

The team also developed a two-way movement design for bottom-up projection, so that the resin could be quickly spread into uniform thin layers – cutting production time from hours to a few minutes.

In the current work, Chen and his team successfully applied this more efficient process to the fabrication of heterogeneous objects that comprise different materials that cure at different rates.

This new process allows heterogeneous prototypes and objects such as dental and robotics models to be fabricated in less costly and more time-efficient ways than ever before, the researchers said.

Chen and his team now plan to investigate ways to develop an automatic design approach for heterogeneous material distribution according to user-specified physical properties, and to find ways to improve the fabrication speed. The researchers presented their findings at ASME’s 2013 International Mechanical Engineering Congress and Exposition in San Diego on Wednesday.

Source: redOrbit Staff & Wire Reports - Your Universe Online

'Pressure cooker' method helps produce better batteries

US researchers claim they have found a way to improve battery technology by using a ‘pressure cooker’ technique to control the battery’s nanostructure.

The engineers from the University of California, Riverside, say creating nanoparticles with a controlled shape in the materials used for batteries’ cathodes could make them smaller, more powerful, more efficient.

They also hope to reduce charge times by modifying the size and shape of the battery components. This could make the technology particularly suitable for electric vehicle batteries, which are a major limiting factor in the cars’ performance.

The researchers have demonstrated their technique with cathodes made from lithium iron phosphate, which has been used in electric vehicles because of its low cost, low toxicity and thermal and chemical stability, but has limited commercial potential because of its poor electric conductivity.

The reactant materials used to make the cathode were heated under pressure with a mix of solvents to control the size, shape and crystallinity of the particles, making the lithium ions in the cathode more mobile and so improving its performance.

‘This is a critical, fundamental step in improving the efficiency of these batteries,’ said lead researcher David Kisailus in a statement.

The research was sponsored by the Winston Chung Global Energy Center and published in the journal Crystal Growth & Design.

Source: http://www.theengineer.co.uk/electronics/news/pressure-cooker-method-helps-produce-better-batteries/1017524.article#ixzz2lYbuR4Vg

Why we might not be able to live on the Moon

The suggestion that regions of the Moon have ancient ice triggered much hope that we could colonise it. Sadly, it’s looking ever less likely that it’s possible.

The US space agency Nasa sells dreams. There’s nothing wrong with that – after all, space and its exploration have always been a source of reverie, from Johannes Kepler’s youthful space-travel fantasy simply called The Dream to visions of the ‘final frontier’. The problem with dreams is that sooner or later you must wake up.

To judge from an article on lunar bases on Nasa’s web site, it’s reluctant to do that. “When multiple spacecraft all found unequivocal evidence for water on the moon it was a boon to possible future lunar bases, acting as a potential source of drinking water and fuel,” the article says. It explains that the atomic components of water – hydrogen and oxygen – on the lunar surface move towards the poles, “where [water] accumulates in the cold traps of the permanently shadowed regions.” Since it was first proposed several years ago, this idea that the polar craters, particularly the so-called Shackleton crater at the south pole, are lined with ancient ice has inspired many hyperbolic newspaper stories about colonising the Moon. But it’s looking ever less likely that it is true.

A new paper in the journal Geophysical Research Letters drives another nail into the coffin of lunar living. It suggests that what was at first taken to be bright, reflective ice in the Shackleton crater is in fact more likely to be white rock.

When the Apollo missions reached the Moon at the end of the 1960s, they brought back a sobering message: it seemed to be a dry, barren dustball. But the modern dream of “water on the Moon” began in earnest in 1994, whenNasa’s spacecraft Clementine orbited the Moon and studied the mineral composition of its surface. The reflections of radio waves beamed into the shadowed polar craters suggested that they might contain ice. But follow-up studies using radio telescopes on Earth failed to find any such evidence.

Then in 1998 another Nasa Moon mission, the Lunar Prospector spacecraft, used a special instrument to search for hydrogen atoms – a possible signature of water molecules – on the Moon’s surface. It detected the hydrogen signals from polar craters, but when at the end of its mission the spacecraft was purposely crashed into a south polar crater in the hope that it might send up a plume of water detectable from Earth, nothing of the sort was observed.

No Moon river

Each alleged sighting of lunar ice provoked new headlines forecasting future moon bases, feeding an apparent public thirst for space colonization. But for scientists, the debate has remained unresolved. In 2009 NASA launched theLunar Reconnaissance Orbiter, designed to map the Moon’s surface in even more detail and carrying several instruments that might be able to detect ice. Last year a team of planetary scientists reported that the south polar Shackleton crater has a bright floor and even brighter inside walls, suggesting that some material has gradually slipped down the slopes onto the bottom of the crater. The researchers suspected that this stuff could be simply lunar “soil”, called regolith because it is really just mineral dust, with no organic matter. Lunar regolith is bright and reflective when freshly exposed – the bombardment from cosmic rays, solar wind and meteorites gradually darkens it, but on the crater’s walls it is particularly well sheltered from such disturbances. But the team also offered the tentative possibility that the bright material could be a very thin layer of rock dust mixed with 20% ice.

Now along comes a team of Japanese space scientists to squash that enticing idea. Led by Junichi Haruyama of the Japan Aerospace Space Exploration Agency (Jaxa), based in Kanagawa, they have analysed data from Jaxa’s lunar orbiter Selene – better known in Japan as Kaguya after a legendary moon princess. Last year the team reported that Selene (which operated from 2007 to 2009) had found rocks made of the mineral anorthosite all over the Moon. This stuff is thought to be formed when meteorites hit the Moon and melt its surface, and the researchers suggested that the Moon might have a thick layer of it several kilometres beneath its surface, created by a massive impact soon after it was formed.

Lunar anorthosite is very pure and bright white, as shown by the lumps of it brought back by the Apollo missions. But here’s the clincher: unlike ice, anorthosite absorbs infrared radiation strongly at a wavelength of 1.25 micrometres, providing a distinctive signature of this mineral. And that absorption was just what was seen by Selene on the inner wall of the Shackleton crater. So it looks as though it isn’t ice.

Haruyama and colleagues don’t rule out the existence of water elsewhere on the Moon, for example hidden away in sub-surface caverns. But they suspect that the amounts might be small. That may still be scientifically interesting, raising questions about how it got there and how it might move around on the surface. Yet without a significant amount of water on the Moon, it is hard to see how any substantial space colony could be established there – the cost of sending up regular water supplies (which would be used not just for drinking but for making hydrogen as fuel) just doesn’t look viable.

That would be a shame, because there’s surely useful science that could be done from a moon base, not least in terms of finding out how this ball of rock formed in the first place (we still don’t really know). It might also literally bring us back down to Earth, forcing us to accept that the universe is a truly inhospitable place, so that we’d better take care to keep our house in order. 

Given the history so far, it would be unwise to imagine that this is the last we will hear of water on the Moon. But it would be unwiser still to start planning to build a colony up there.  

Source: bbc.co.uk/future

The Earthscraper

A team of Mexican architects have designed a 65-story glass and steel pyramid to sit in the middle of Mexico City's most historic plaza. But, if it ever gets built, you won't see it anywhere on the skyline.

That's because it would be the world's first ever "earthscraper" -- a 300-meter deep office and living space with ambitions to turn the modern high-rise, quite literally, on its head.

"There is very little room for any more buildings in Mexico City, and the law says we cannot go above eight stories, so the only way is down" explains Esteban Suarez, co-founder of BNKR Arquitectura, the firm behind the proposals.

"This would be a practical way of conserving the built environment while creating much-needed new space for commerce and living," he added.

But would it really be that practical? The design, which would cost an estimated $800 million to build, is the shape of an inverted pyramid with a central void to allow for some much-needed natural light and ventilation.

Suarez says the first 10 stories would hold a museum dedicated to the city's history and its artifacts. "We'd almost certainly find plenty of interesting relics during the dig -- dating right back to the Aztecs who built their own pyramids here," he says.

The following 10 floors are assigned to retail and housing, with the remaining 35 intended for commercial office space, says Suarez.

Suarez concedes that getting natural light and fresh air down to the lower floors will be a problem and he is investigating a "system of fiber optics" that could deliver sunlight from the surface.

The design also includes a series of a series of "earth lobbies" that would store plants and trees with the intention of improving air-quality and, no doubt, the gloomy subterranean landscape.

Suarez says renewable energy could be generated by a turbine powered from collected groundwater. Enough to keep the lights on in an underground office block 24 hours a day? "I couldn't say at this stage" replies Suarez.

But although it has the hallmarks of a fossil-fuel guzzling Goliath -- and a name to match -- Suarez says the "Earthscraper" has great eco-credentials. "In many ways, this project is all about the environment -- not just in how we preserve our historic skyline, but how we prevent the serious problem of urban sprawl into the countryside," he says.

According to the 32-year-old architect, Mexico City's main square -- commonly known as the "Zocalo" -- is one of the biggest city plazas in the world. "It's a massive empty plot, which makes it the ideal site for our program," he said.

To conserve the numerous activities that take place on the 190,000 square-foot plaza throughout the year -- including concerts, protests, open-air exhibitions and military parades -- the void will be covered with a glass floor that Suarez believes will allow the life of the "Earthscraper" to blend with everything happening on top.

Source: http://edition.cnn.com/

Toylike blocks make lightweight, strong structures

Instead of reducing parts, engineers suggest building planes from thousands of identical pieces

A carbon-fiber skeleton of Tinkertoy-like building blocks is 10 times as stiff as structures of similar densities. And because the framework is made of mostly identical pieces, broken parts can be easily swapped out for new ones, its inventors report in the Aug. 16 Science. The new design could one day form light, stiff, easy-to-repair bones of airframes, bicycles, bridges and even buildings.

“It’s fascinating,” says materials scientist Rainer Adelung of Kiel University in Germany. “When you read this article, you think, ‘Why hasn’t anyone done this before?’ It’s a simple idea, but it has such a large impact.”

For years, fancy bicycles and luxury cars have used glued-together carbon fibers, called composites, to trim weight from their frames. Now, manufacturers are starting to craft huge sections of airplanes in single swaths of the lightweight materials. Fewer parts means fewer joints, which tend to be heavy and tricky to fix.

So manufacturers want to make even bigger plane pieces. In 2008, Spirit AeroSystems, a manufacturer that makes parts for Boeing and Airbus, came to MIT materials engineer Kenneth Cheung and his lab leader, Neil Gershenfeld, with a wild idea: What if they could 3-D print an entire plane in one gigantic piece?

So Cheung and Gershenfeld came up with an idea to assemble a plane out of millions of identical pieces, rather than one enormous one.Cheung and Gershenfeld had doubts. Though a giant piece of composite has fewer joints, it can be hard to repair, Cheung says. When composites break, they break big-time. A wallop violent enough to crack a composite part in one place has a domino effect. The energy of the crash rebounds through the part, busting it in multiple places.

Cheung played with several designs, slicing shapes out of cardboard and plywood before settling on the repeatable unit: a flat “X” of carbon-fiber composite, with a hole in the center and a loop at the end of each arm. The unit is 2 inches long, Cheung says, but could scale to virtually any size. “You can think of it as a really high-performing Lego,” he says.

Cheung hooked the Xs together to make cube-shaped lattices of repeating triangular pyramids and then crushed the structures to measure their strength and stiffness. An 8-inch cube about as heavy as an egg could hold more than 650 pounds before crumpling, Cheung says. And given the material’s very low weight, Adelung says, the lattice is “remarkably stiff.”

The geometry of the cube’s lattice is a key part of its stiffness and strength. “If you built a bunch of triangular pyramids out of toothpicks and marshmallows, you could probably rest a book on top,” Cheung says.

When Cheung and Gershenfeld’s composite structures hit their breaking point, individual pieces in the lattice snapped, confining breaks to discrete spots. This useful property would allow manufacturers using the design to gain structural damage control. “You could incrementally replace single parts, knowing that the structure is completely stable while going through that process,” Cheung says. He envisions using robots to build the structures and crawl through them, inspecting parts and switching out cracked pieces. 

The researchers also tinkered with their structures’ flexibility by plugging thinner, more bendable, pieces into the lattice. By fitting these pieces into specific parts of the lattice, the researchers could force certain areas to buckle while keeping other areas rigid. In an airplane, this type of design could let pilots maneuver their crafts by flexing the wings instead of lifting and lowering flaps.

The structures don’t come close to rivaling the strength and stiffness of denser materials, says James Tour, a materials chemist at Rice University in Houston. But they’re incredibly lightweight — and for cars, planes and spacecraft, he says, “weight is a huge, huge concern.”

This September, Cheung will join NASA to craft lattices for structures in space.

Source: sciencenews.org (Written by Meghan Rosen)

New Suspension Generates Power From Bumps and Curves

Every time your car bounces or sways, energy is being lost to the ether, and two companies have developed a way to harness that energy to boost fuel economy while keeping your ride taut and smooth.

ZF Friedrichshafen AG and Levant Power Corp. have created the world’s first active suspension system equipped with an energy recovery function. It’s called the GenShock and if an automaker signs up with the project, it could hit roads within the next few years.

The principle behind the system is to recoup lost energy from the motions of the suspension and then feed that power back into the car’s electrical system. Students at MIT developed a similar system in 2009, and claimed to generate enough power to replace a vehicle’s alternator.

The system from ZF and Levant uses active dampers that change the pressure inside the shock based on the type of road surface, and a new valve mounted outside the shock, along with a control unit, gear pump, and electric motor, controls the flow of fluid, smoothing out the ride. When there’s an overabundance of motion created by braking, accelerating or running over rough terrain, fluid is pushed through the pump, driving the electric motor and converting the kinetic energy into electricity. And the rougher the road surface the more energy it can create.

Even better, because each shock can be individually controlled, the system can push more fluid into the shock to raise or lower the vehicle, so the car jack’s days could be numbered.

Source: wired.com

The Terrafugia TF-X: The Flying Car That Will Change The World

Remember when you were a kid and dreamed of one day flying through town? Well, it seems as though we’re one day closer, as a real flying car may be on the market sooner than you think.

Although the company Terrafugia has been working on a flying car called the Transition for years that’s expected to hit the market in 2015, a better option has seemed to come along.

The Transition isn’t exactly a take-off-in-traffic flying car, but rather a small airplane that happens to be street legal, as well. The clunky machine needs a runway to take off in the same way as a traditional airplane.

At a price tag of $300,000, the Transition doesn’t deliver the way a flying car should.

The future, however, is here. The TF-X, Terrafugia’s recently announced alternate model, is the flying car we’ve all been waiting for.

The TF-X is a sleek looking car, shaped like a bullet and when it comes time to fly, it opens up gracefully the way a flying car out of a science-fiction movie would.

Taking off with rotor propellers, the TF-X eventually makes the transition to a 300-hp engine that allows jet-like flight at speeds up to 200 mph.

With a flying range of 500 miles and a four person capacity  with “in car-like comfort,” the TF-X may be the flying car thatactually is a flying car.

We will certainly be bypassing the Transformation and save our money for the TF-X.

Source: http://elitedaily.com

Glasgow scientists create single-pixel camera for 3D images

Scientists in Glasgow have discovered a low-cost way to create 3D images.

Their system uses detectors which have a single pixel to sense light instead of the millions of pixels used in the imaging sensors of digital cameras.

The detectors can "see" frequencies beyond visible light, which researchers say could open up new uses for 3D imaging in medicine and geography.

They said the single-pixel detectors cost "a few pounds" compared to current systems, which cost "thousands".

It is hoped that the system's ability to senses wavelengths far beyond the capability of digital cameras and its low cost, could make it a valuable tool for a wide range of industries.

Researchers said possible uses could range from locating oil to helping doctors find tumours.

Crossword patterns

Prof Miles Padgett led the team at University of Glasgow's School of Physics and Astronomy, which developed the technique.

He said: "Single-pixel detectors in four different locations are used to detect light from a data projector, which illuminates objects with a rapidly-shifting sequence of black-and-white patterns similar to crossword puzzles.

"When more of the white squares of these patterns overlap with the object, the intensity of the light reflected back to the detectors is higher.

Continue reading the main story

"A series of projected patterns and the reflected intensities are used in a computer algorithm to produce a 2D image."

He said a 3D image was then created by combining images from the four detectors using a well-known technique called "shape from shade".

This 3D computational imaging, or ghost imaging produces detailed images of objects in just a few seconds.

Conventional 3D imaging systems uses multiple digital camera sensors to produce a 3D image from 2D information.

Careful calibration is required to ensure the multi-megapixel images align correctly.

Beyond the visible

Prof Padgett said: "Our single-pixel system creates images with a similar degree of accuracy without the need for such detailed calibration."

Lead author on the paper Baoqing Sun said: "It might seem a bit counter-intuitive to think that more information can be captured from a detector which uses just a single pixel rather than the multi-megapixel detectors found in conventional digital cameras.

"However, digital camera sensors have a very limited sensitivity beyond the spectrum of visible light, whereas a single-pixel detector can easily be made to capture information far beyond the visible, reaching wavelengths from X-ray to TeraHertz."

The team's paper, 3D Computational Imaging with Single-Pixel Detectors, is published in the journal, Science.

Source: bbc.co.uk

Sound cloaks enter the third dimension

Concept could lead to sonar-defeating submarines or noise-cancelling highway barriers

A simple plastic shell has cloaked a three-dimensional object from sound waves for the first time. With some improvements, a similar cloak could eventually be used to reduce noise pollution and to allow ships and submarines to evade enemy detection. The experiments appear March 20 in Physical Review Letters.

“This paper implements a simplified version of invisibility using well-designed but relatively simple materials,” says Steven Cummer, an electrical engineer at Duke University, who was not involved in the study. Cummer proposed the concept of a sound cloak in 2007.

Scientists’ recent efforts to render objects invisible to the eye are based on the fact that our perception of the world depends on the scattering of waves. We can see objects because waves of light strike them and scatter. Similarly, the Navy can detect faraway submarines because they scatter sound waves (sonar) that hit them.

So for the last several years scientists have been developing cloaks that prevent scattering by steering light or sound waves around an object. The drawback of this approach, however, is that it requires complex synthetic materials that are difficult to produce.

José Sánchez-Dehesa, an electrical engineer at the Polytechnic Institute of Valencia in Spain, and his colleagues pursued a different method: Instead of preventing sound waves from hitting an object — in this case an 8-centimeter plastic sphere — they built a cloak to eliminate the scattered waves left in the sphere’s wake.

Using computer algorithms, the researchers came up with a design made up of 60 rings of various sizes that form a cagelike structure around the sphere. Simulations indicated that sound waves scattering off the sphere and the ringed cloak would interfere with each other and cancel out. (Noise-cancelling headphones exploit this phenomenon by emitting sound waves that minimize ambient sounds in a room.)

Because the cloak did not need to steer sound waves in complicated ways, Sánchez-Dehesa and his team built it out of plastic with the help of a 3-D printer.  They hung their creation from the ceiling of an echo-free chamber, pointed a speaker at it and played a range of sound frequencies. For most frequencies, the sphere scattered an easily detectable amount of sound. But at 8.55 kilohertz — an audible high pitch — the cloaked sphere became imperceptible to the sensors behind it.

The study marks the first time scientists have ever cloaked a three-dimensional object from sound. That’s probably music to the ears of the U.S. Office of Naval Research, which partially funded the study to explore the possibility of sonar invisibility.

However, this cloak is just a small step toward stealth submarines. It has to be custom designed and built for each object, and it works only for a narrow frequency range coming from one direction. If the speaker had been set up anywhere else, the cloak would not have worked. Sánchez-Dehesa’s team plans to develop broadband and multidirectional cloaks.

But Cummer points out that even a limited cloak can have useful applications. He suggests that structures capable of manipulating a specific sound frequency from one direction could help minimize noise pollution from a congested highway. “The cloak does one thing quite well, with a very simple structure,” he says.

Source: sciencenews.org