First flapping, two-winged aircraft takes flight

The world’s first successful flight of a self-powered, rudderless, flapping aircraft has been achieved by engineers from AeroVironment.The NAV, or nano air vehicle, operates by using two flapping wings, which also function as the rudder, elevators, ailerons and engine. With its two wings, the NAV is able to hover, move forward and backwards, and change its elevation.

In flight, the NAV almost appears to replicate the movements of a hummingbird.Simplified, most airplanes and helicopters today fly using the same principle: Air rushing over a shaped and immovable wing or helicopter blade produces an area of high pressure below the wing and an area of low pressure. The difference pushes the wing up in the direction of low pressure, creating lift.

An airplane is steered using adjustable flaps on the ends of the wings and at the tail, which also help steady the aircraft.

“It’s extremely complicated and technically challenging to come up with ways to control an aircraft with two flapping wings,” said Matt Keennon of AeroVironment, “but this is the closest anyone has come to a rudderless, flapping aircraft.

“AeroVironment wouldn’t explain how the two wings accomplish flight, citing its contract with the Defense Advanced Research Projects Agency DARPA.

However, Guido de Croon and Rick Ruijsink at Delft University of Technology in the Netherlands have their own theory about how AeroVironment’s NAV flies. The two men, along with their colleagues at Delft University, have created three flapping-wing aircraft of their own, known as Delfly I, II and Micro. The Delflys are flapping-wing aircraft, but differ significantly from AeroVironment’s NAV. The Delflys have four flapping wings and a rudder, which in theory makes it easier to control than the rudderless, two-winged NAV.

According to Ruijsink and de Croon, the shape of the wings isn’t quite as important for flapping-wing aircraft as it is for fixed-wing aircraft. While a fixed-wing uses a smooth flow of air over the wings to create lift, a flapping-wing separates the air into two flows.

The two European researchers also suspect that AeroVironment changes the wing’s angle to move NAV forwards or backwards. Tipping the lead edge up would move the airflows to the rear of the wing, moving the aircraft backwards. To move forward, the lead edge of the wing likely tips down, moving the airflows, and the craft, forward.

Achieving flight with a rudderless, flapping-wing aircraft is certainly an accomplishment, but like any DARPA-funded project, the defense agency asks for more. Possible applications for this small, maneuverable aircraft could include spying on enemies or finding victims in a natural disaster.

- via MSN

Cool, check out the video. What is the power supply and how long does it last?

One nano-step closer to weighing a single atom

Such ultrasensitive measurements could ultimately be used in areas such as medical research and diagnostics, enabling the detection of minuscule disease-causing agents such as viruses and prions at the single molecule level.

Researchers are interested in nanosized materials because the smaller the components of a detection device, the more sensitive it is.

In this study, the team from the University of Melbourne, Argonne’s Center for Nanoscale Materials in Illinois and the University of Chicago synthesized and studied tiny gold rods with a width 5000 times smaller than the thickness of a human hair.

The work will be published online this week in Nature Nanotechnology.

Professor John Sader from the Department of Mathematics and Statistics, University of Melbourne says that in the same way as a classroom ruler decreases its frequency of vibration when an eraser is attached, nanomechanical mass sensors work by measuring their change in vibration frequency as mass is added.

The sensitivity of such nanomechanical devices is intimately connected to how much energy they displace. So researchers needed to understand how damping (loss of energy) is transferred both to the fluid surroundings and within the nanostructures. With the lower the damping, the purer the mechanical resonance and higher the sensitivity.

It has not previously been possible to determine the rate at which vibrations in metal nanoparticle systems are damped, because of significant variations in the dimensions of the particles that have been studied – which masks the vibrations.

However, by studying a system of bipyramid-shaped gold nanoparticles with highly uniform sizes and shapes, the researchers overcame this limitation.

via One nano-step closer to weighing a single atom | The Melbourne Newsroom.

Video shows nanotube spins as it grows

Check out the video here:

New video showing the atom-by-atom growth of carbon nanotubes reveals they rotate as they grow, much like the halting motion of a mechanical clock’s second hand.

VIDEO CREDIT: Video courtesy of S. Purcell, LPMCN/Université Lyon1/CNRS. Posted with permission from Nano Letters DOI: 10.1021/nl901380u. Copyright 2009 American Chemical Society.

FEM video from Université Lyon1/CNRS shows the rotation of the nanotube during growth. The observation helps confirm a new rotational theory of carbon nanotube growth offered by Rice researchers in February.

Published online this month by researchers at France’s Université Lyon1/CNRS and Houston’s Rice University, the research provides the first experimental evidence of how individual carbon atoms are added to growing nanotubes.

“The key issue for realizing the potential of carbon nanotubes has always been better control of their growth,” said team lead Stephen Purcell of the Université Lyon1/CNRS. “Our findings offer new insights for better measurement, modeling and control of nanotube growth.”

Carbon nanotubes are long, hollow cylinders of pure carbon. They are hair-like in shape but are about 100,000 times smaller than human hair. They are also about six times stronger than steel, conduct electricity as well as copper and are almost impervious to radiation and chemical destruction. As a result, scientists are keen to use them in superstrong, “smart” materials, but they need to better understand how to produce them.

“The images from Dr. Purcell’s lab show the atom-by-atom ’self assembly’ of a nanotube,” said Rice co-author Boris Yakobson, professor in mechanical engineering and materials science and of chemistry. “The video offers compelling evidence of the rotational motion that accompanies nanotube growth. It brings to mind Galileo’s famous quote, ‘And yet, it does turn.’”

via Rice University | News & Media.

Carbon Nanotubes — tiny tubes about 10,000 times thinner than a human hair — consist of rolled up sheets of carbon hexagons. Discovered in 1991 by researchers at NEC, they have the potential for use as minuscule wires or in ultrasmall electronic devices. – ibm

What makes them spin? Spin may be built in to the universe.

Swine flu spreads in Britain

British health officials reported 100,000 new cases of swine flu in the country in the week ending July 17, double the number the week before.

The country has reported more cases of flu caused by the H1N1 virus than any other except the United States and Mexico, The Times of London reported Saturday. British officials worry the country could run out of beds in hospital intensive-care wards if the disease continues to spread this winter.

The country has begun screening incoming passengers at Heathrow International Airport for symptoms of swine flu. At least 160 British citizens were in quarantine in China, Singapore, India and Egypt because of swine flu fears.

Pharmacies have been reporting a run on surgical masks and other supplies, CNN reported. One pharmacy said a six-month supply of masks was snapped up in three days.

“People are very panicked,” an assistant at Zafash Pharmacy in southwest London said. “That’s why everyone is running for thermometers, surgical masks and anti-bacterial gels.”

via Swine flu spreads in Britain – UPI.com.

The record-breaking kayaker risks life and limb

Perched on the brink of a 186ft drop, this was the moment when Tyler Bradt probably felt the urge to start frantically paddling backwards.

Less than four seconds later, he was celebrating a world record for kayak descents.

The 22-year-old American touched 100mph as he plummeted over Palouse Falls in eastern Washington.

‘Then an acceleration, speed, and impact unlike anything I’ve ever felt before. I wasn’t sure if I was hurt or not. My body was just in shock.’

Bradt, from Montana, had prepared for the attempt by plunging over 70-80ft high waterfalls in Oregon.

His previous best attempt was 107ft down Alexandra Falls along the Hay River in Canada’s Northwest Territories in 2007.

He was spurred on to conquer Palouse Falls by Olivia’s 127ft fall in the Amazon.

In preparation Bradt visited Palouse Falls several times to observe the water and to see if it was humanly possible to survive the descent.

The first time I saw the Palouse, I knew it was runnable,’ he said.

‘There’s a smooth green tongue of water that carries about a third of the way down the falls. That was my route.’

As rescue teams waited at the base of the falls Bradt calmly steered his fiberglass kayak into the raging water.

After disappearing under the water he emerged within six seconds with his broken paddle and sprained wrist.

‘Considering the waterfall, the injuries were pretty minor,’ he said.

Bradt said he wanted to attempt the plunge not to set a record but to show what humans are capable of achieving.

The motivating factor for all this was just that I thought it was possible. I wanted to do it, I guess, because I can.

‘It was a calculated risk, no doubt dangerous but also one of the most amazing days of my life.

‘It’s a personal thing and nothing exterior, especially negativity, affects that.’

Bradt has faced criticism that his stunt will encourage others to try the extreme sport of kayak free-falling.

But he dismissed the suggestions, saying: ‘I hope it encourages people not to run huge waterfalls but to understand that the only limits that exist are the ones you create, no matter what you are doing.’

via Pictured: The record-breaking kayaker who risked life and limb in a 186ft waterfall drop | Mail Online.

Taiwan, China leaders exchange 1st direct messages

The Taiwanese and Chinese presidents swapped messages Monday, the first such exchange since the two sides split amid civil war 60 years ago.

They did so in their capacity as ruling party leaders, rather than as heads of state, to skirt the disputed issue of Taiwan’s sovereignty.

It was the latest sign in rapidly improving relations between the once bitter enemies. In the 14 months since Taiwanese President Ma Ying-jeou took power, those ties have morphed from mutual suspicion and antipathy to bilateral expressions of amity and understanding, amid thriving trade and investment.

According to a statement from Ma’s Nationalist Party, Chinese President and Communist Party chief Hu Jintao sent a telegram to the Taiwanese leader congratulating him on his election Sunday as party chairman, and told him he hopes his party can work with the Nationalists in the best interest of both sides.

via Taiwan, China leaders exchange 1st direct messages – Yahoo! News.

The Komfysaki

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Stop Motion Sand Sculpture

Interesting thing to try with your video camera:

Women are getting more beautiful

FOR the female half of the population, it may bring a satisfied smile. Scientists have found that evolution is driving women to become ever more beautiful, while men remain as aesthetically unappealing as their caveman ancestors.

The researchers have found beautiful women have more children than their plainer counterparts and that a higher proportion of those children are female. Those daughters, once adult, also tend to be attractive and so repeat the pattern.

Over generations, the scientists argue, this has led to women becoming steadily more aesthetically pleasing, a “beauty race” that is still on. The findings have emerged from a series of studies of physical attractiveness and its links to reproductive success in humans.

In a study released last week, Markus Jokela, a researcher at the University of Helsinki, found beautiful women had up to 16% more children than their plainer counterparts. He used data gathered in America, in which 1,244 women and 997 men were followed through four decades of life. Their attractiveness was assessed from photographs taken during the study, which also collected data on the number of children they had.

via Women are getting more beautiful – Times Online.

Real Oakland officer arrests fake officer who tries to pull him over

Oakland police say a man impersonating a police officer tried to pull over a real undercover officer and was arrested.

Police say 21-year-old Antonio Fernandez Martinez of Oakland was arrested Wednesday in the Fruitvale district after trying to pull over an unmarked police vehicle. Martinez was driving a Ford Crown Victoria outfitted with flashing lights, a microphone and speakers.

Martinez, a convicted car thief, will have his felony probation revoked and could face a prison term.

The officer, Jim Beere, says Martinez probably thought he’d be an easy mark to rob.

via Real Oakland officer arrests fake officer who tries to pull him over.