Eye-safe dazzler could prevent eye injuries

Eye-safe dazzler could prevent eye injuries

For daily technology stories, visit www.NewScientist.com/technology OWEN FRANKEN/CORBIS TECHNOLOGY Halt or we’ll dazzle you THE Pentagon is working...

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For daily technology stories, visit www.NewScientist.com/technology

OWEN FRANKEN/CORBIS

TECHNOLOGY

Halt or we’ll dazzle you THE Pentagon is working on a laser dazzler that will force drivers to stop without harming their eyes. When a vehicle approaches a checkpoint at speed, ignoring warning signs to slow down, troops do not know whether the driver is simply careless or a suicide bomber. They need a clear and harmless way of forcing drivers to stop. Green laser dazzlers designed to temporarily blind drivers were sent to US forces in Iraq and Afghanistan for just this purpose. But at short range they can damage the eye, and a number of US troops and civilians have ended up in hospital with eye injuries after “friendly fire” incidents. Now the US Department of Defense’s Joint Non-Lethal Weapons Directorate (JNLWD) in Quantico, Virginia is developing a pulsed laser

designed to prevent eye damage. Its wavelength means a portion of the light is absorbed by the vehicle windscreen, vaporising the outer layer of the glass and producing a plasma. This absorbs the rest of the

“US troops and civilians have been sent to hospital with eye injuries after ‘friendly fire’ incidents” pulse and re-emits the energy as a brilliant white light that is dazzling but harmless. Because the light is emitted from the windscreen, the effect on the driver’s eyes should be the same regardless of the vehicle’s distance from the laser. Scott Griffiths of the JNLWD says it hopes to have a working prototype ready by next year.

-Close your eyes–

Taxibot could save airlines billions

Feathers hold hydrogen promise

ROBOTIC tractors could one day be used to tow aircraft between the airport gate and the edge of the runway. This could save airlines $7 billion a year in fuel costs and cut 18 million tonnes of carbon dioxide from aviation’s annual emissions. Jet engines run at their most inefficient when used to propel planes around the taxiways. To get around this problem, the European aircraft manufacturer Airbus and the military robot maker Israel Aerospace Industries are working together to create a “taxibot” that docks with an aircraft’s nose landing gear to tow the plane. Pilots would guide the taxibot using their regular joystick and pedal controls. “To the pilot it would feel no different to normal taxiing with the engines,” says Airbus engineer Marc Lieber.

NEED a cheap way to store hydrogen? Put chicken feathers in your tank. The unlikely material may one day compete with more high-tech solutions such as carbon nanotubes for storing hydrogen for fuel-cell-powered vehicles. Hydrogen is difficult to store safely in a tank because it is potentially explosive. So researchers are looking for materials that can stabilise hydrogen by weakly bonding with it. Richard Wool’s team at the University of Delaware in Newark heated chicken feather fibres to 400 °C without burning. The

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The quantity of data in exabytes (1018 bytes) sent round the world on 15 June Source: Digital Britain report, published by UK government last week

process resulted in stable, porous carbonised fibres. When cooled to -266 °C, the material could store almost 2 per cent of its weight in hydrogen – almost as much as carbon nanotubes. While still shy of the US Department of Energy’s target of 6.5 per cent, the feathers’ abundance and price hold promise: chicken feathers are a huge waste problem in Delaware. “You can afford carbon nanotubes if you want to go to the moon, but if you just want to go to the grocery store, you need something cheaper,” says Wool, who presented the results last week at the Technologies for a Hydrogen Economy symposium at the University of Maryland University College in Adelphi.

“Another month for me!” Japanese astronaut Koichi Wakata, who is on board the International Space Station, reacts favourably to the news that a fuel leak has prevented the launch of the space shuttle Endeavour, delaying his ride home until at least 11 July (NASA Twitter feed, 17 June)

27 June 2009 | NewScientist | 19