Technology

NASA appears to have cancelled its research into space-based solar power (SBSP) systems – orbiting solar arrays that beam microwaves to receivers on the ground, where the energy is converted to electricity.

Seen as one technology for combating climate change, SBSP faces major challenges – including the cost of launching hundreds of square kilometres of solar arrays to an altitude of 36,000 kilometres. Now a letter leaked to the NasaWatch.com blog says the space agency “does not have the resources available to support a proposed demo for SBSP”.

Advocates of the technology are still urging President-Elect Obama to adopt it by posting pro-SBSP research papers on his change.gov website. Some members of his transition team are also thought to support solar power from space.

BEING held in a robot’s steely grasp need not be as uncomfortable as it sounds.

Previous attempts to use robots to guide limbs have required the person concerned to be strapped to them. Now a team at the University of Karlsruhe , Germany, is developing a human-sized machine which is able to lightly hold a person’s forearm and steer

36gigabytes of data have been sent back by NASA’s Spirit and Opportunity rovers during their five years on Mars

Forensics experts and road-accident investigators could soon revisit the scene of a crime without leaving their office, thanks to a 3D scanner that “paints” a virtual model of the area.

The hand-held scanner makes it possible to record a scene with millimetre accuracy and creates a computerised 3D model that can be navigated as if investigators were at the site, says Robert Valkenburg of Industrial Research in Auckland, New Zealand, which developed the technology.

The device consists of a laser scanner coupled to a digital camera. The scanner creates a 3D model of the scene, onto which images from the camera are overlaid. To ensure this is done accurately, the device needs to keep a constant track of its position. It achieves this using a sort of local GPS

system, in which a number of “satellites” placed on tripods around the scene emit laser pulses. These are detected by sensors fitted to the scanner, allowing the device to calculate its position by triangulation. At least 20 of these laser beacons are needed, says Valkenburg – the more beacons, the greater the accuracy.

As the device is swiped in front of objects, walls or other surfaces, they automatically appear on screen “like brushstrokes”, says Valkenburg, as part of the emerging 3D model. A number of other scanning technologies are available, but none can capture scenes with such photorealism, he adds.

The device could also be used to scan heritage sites, historical artefacts and movie and video game props, Valkenburg says.

AN EVERLASTING CRIME SCENE

them in the appropriate direction.The team has equipped the

robot with a camera at neck height that detects the person’s position. A sensor on its palm guides its movements as it reaches out to touch the person’s forearm, while touch sensors on its fingertips adjust its grip to prevent it being too heavy-handed. If the person starts to wriggle, the robot quickly releases its hold.

The work was presented at the Humanoids 2008 conference in Daejeon, South Korea, last month.

Touch-screen technology looks set to flood shopping malls in 2009. At the Consumer Electronics Show this week in Las Vegas, KYE Systems of Taiwan introduced hi-fi speakers with an illuminated touch panel that lets users change volume, bass and treble “with a glide of the finger”. It also introduced a digital photo frame that allows the picture or slide show to be changed using a similar touch screen.

Nanotechnologists have built a mechanical switch that changes with temperature. A team at Osaka University in Japan constructed a carbon nanotube that moves back and forth inside a larger closed nanotube (Nano Letters, DOI: 10.1021/nl802323n). Electrostatic forces bind the internal nanotube to one end of its container, but heat breaks this bond, allowing the tube to slide and bind to the other end.

GIZMO

INFORMATION COLLEGE STUDENTS SAY THEY

INCLUDE ON THEIR SOCIAL NETWORKING SITES

FULL PROFILE VIEWABLE 74%

INSTANT MESSAGING ADDRESS 49%

EMAIL ADDRESS 35%

PHONE NUMBER 9.4%

HOME ADDRESS 9.4%

PHOTOGRAPH 86%

CALL ME

One in 10 students display their phone number on their social networking web page

Silicon Valley venture capitalist Paul Holland, a general partner at Capital Foundation, puts a brave face on the prospects for 2009 on the principle that bad times produce the best investment opportunities (The New York Times, 4 January)

“Cisco was founded two weeks before a stock market crash”

–Always there if you need it–

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Lack of cash sinks power from space

The robot with the tender touch

www.newscientist.com 10 January 2009 | NewScientist | 19