July 2008 Archives

Could an optical technique used every day in laboratories all over the world help to answer the fundamental question of are we alone in the Universe? A team of scientists from the US and the UK certainly hopes so. The group believes that its laser fluorescence equipment can be made to withstand the harsh environment on Mars to search for life on the planet.

The researchers propose that the system could operate on any Mars lander or rover and be made ready for launch in just five years. The key challenge they face is to make the instrument light enough to be flown, and resilient enough to survive the cold, -120°C Martian nights.

Michael Storrie-Lombardi and Jan-Peter Muller, of the Mullard Space Sciences Laboratory in the UK are carrying out experiments both in the laboratory and at Silver Lake in California, US - a well-known Mars analogue study site. "Being able to test the fluorescence signal both under laboratory conditions and in the field has been critical in ensuring the system will work on the surface of Mars," said Muller.

The approach uses ultraviolet fluorescence to illuminate soil and rock in search of tell-tale signs of life. In particular the group is searching for chemical compounds called polycyclic aromatic hydrocarbons (PAHs), which are believed to be one of the earliest forms of organic matter in the Universe. And, just like living organisms, PAHs fluoresce when excited by ultraviolet light.

"While using fluorescence to illuminate organic material has been carried out for decades, light sources were too large and unwieldy to use for a robotic mission to another planet," said Storrie-Lombardi. "However, new generations of LEDs, which are very small, reliable and energy efficient make this possible."

"Placed on a Mars rover, one of these LEDs positioned a few centimetres from a target can easily provide enough light to produce fluorescence in small PAHs," Storrie-Lombardi added. "But even more encouraging is the very recent development of a small 375 nm laser diode that can illuminate geological layers and crevices high up on otherwise inaccessible rock outcrops."

The tool is ideal for initial surveys as it requires no sample preparation, does not destroy sample material and requires only electrical power to operate, conserving precious water and other consumable resources for sister instruments.

If you want to find out more about this work, the team has just published a paper in the journal Geophysical Research Letters.

A robot snake that can slide around narrow and intricate pipes checking for leaks along the way may sound far-fetched, but that's exactly what scientists in Norway are working on.

Cybernetic experts are joining forces with optical scientists at SINTEF to develop an inspection robot that will be able to move in pipes of various diameters, right down to 20 cm.

The group is building on the experience and knowledge acquired with previous snake robots called Anna Konda and AiKo. Now, it is developing an intelligent pipe inspection robot on wheels that will be able to climb, navigate intersections and at any given time know its location in the pipe system.

"We want to develop a robot with 10 or 11 joint modules, each with an identical pair of wheels cast in plastic," said Jens Thielemann, from the Optical Measurements and Data Analysis department at SINTEF. "The robot will function as a train when operating horizontally. Such robots already exist, but we want to develop a robot that can climb too."

A time-of-flight camera will provide the robot's vision, allowing it to navigate and move forward on its own. "The robot knows when a left or right turn is approaching and also contains a built-in path description detailing what tasks it should carry out in different situations," added Thielemann.

When the robot enters a vertical pipe, it will lift its head to meet the wall. It can then either move sideways with its abdomen against the pipe and twist itself upwards or it can topple backwards, attach itself to the pipe wall and roll upwards.

The scientists emphasise that the project is at the design stage but hope to demonstrate a prototype model by the end of the year. The final version of the robot will be constructed of aluminium and measure 1.5 m in length.

At first I wasn't sure how Sony could claim an energy efficiency of 232% for its new Bravia JE1 series of LCD televisions, but the answer was in the small print.

Under Japanese regulations, the standard reference point for the power consumption of a 32-inch LCD screen is 200 kWh per year, designated as 100%. Lower consumption is expressed as a higher percentage compared to the benchmark. Anything above a 164% rating is entitled to receive a five-star Energy Saving label.

By that measure Sony's existing Bravia KDL-32J1 series comes in at 173% energy efficiency, with an annual power consumption of 115 kWh per year.

The new JE1 screens go further, hitting an efficiency of 232% for the KDL-32JE1, said to be the highest on the market for a 32-inch screen, while also reducing the momentary power consumption to 89 W.

According to Sony, the secret lies in the use of high-efficiency fluorescent tubes, capable of delivering higher luminance efficiency at lower electric voltage, along with specialized optical film that possesses a higher light transmission rate.

With the KDL-32JE1, Sony has also started to recycle the waste material generated during the production of the optical film used in its LCD TVs, claiming that doing so will effectively reduce the CO₂ emissions from its production process by an impressive 40%.

Sony already practices in-house recycling to produce flame-retardant polystyrene for its Bravia sets, and some of that apparently recycles plastics from CRT TVs. As shipments of LCD TVs overtook CRT for the first time last year, this seems only right and proper, evolution in action.