cafecuriosity

Revealing Hidden Charms

One of the charming necessities of live as an impoverished artist is the economic imperative to recycle materials - particularly unsuccessful canvasses and boards. This poses a problem when the artist becomes eminently collectable and has spawned a new geek sport - peering behind layers of old paint for ghostly images of pictures past. Recently, one such team got lucky when they detected a woman's portrait behind Vincent van Gogh's 'Patch of Grass'. Drawing collaborators from the Delft University of Technology and the University of Antwerp, the team used synchrotron radiation induced X-ray fluorescence spectroscopy, a new technique that measures the fluorescence of each chemical element, allowing large areas of canvass to be mapped quickly and in great detail. Art historians suspect around 30% of van Gogh's paintings may have been painted over, so the hunt is on - for funding as much as hidden images!  http://www.tudelft.nl/live/pagina.jsp?id=6383a391-d2c6-4341-bcd0-62cba4cff50b&lang=en   Image: Hidden portrait of an unknown woman behind Vincent van Gogh's Patch of Grass', Delft University of Technology

Automating Distruction

There's nothing like seemingly endless insurgency wars to stimulate human ingenuity. Iraq and Afghanistan are re-imagining robotics in labs such as Washington University in St Louis, where the computer science and engineering faculty are designing the US Military's next generation of robots. Early battlefield robots required a clumsy and heavy laptop and joystick for control - bringing a whole new meaning to 'Road Warrior'. The new toys use nothing more exotic than a Wii controller. Much easier to work with when people are shooting at you, as well as being cheaper and lighter to hump around! As well as changing the physical nature of the machines, imagination is being applied to how these metal servants are deployed. Robots now perform battlefield reconnaissance, making UAVs almost ubiquitous in the skies over the Afghanistan-Pakistan border. They already detect explosives and act as weapons carriers. Tomorrow will see the advent of self-driving trucks (being a truck driver is now one of the more hazardous occupations in a war zone). Unlike R2D2, these buckets of bolts are more autonomous systems than the intelligent decision making weapons wrought on the silver screen in 'Terminator' and by 2020 could make up 30% of the US Army. Imagine that, an army of Obi-won worshipping geeks, just the thing to put the frighteners into the Taliban!   http://news-info.wustl.edu/tips/page/normal/12080.html   Image: 1. Soldier humping a Packbot, iRobot, 2. iRobot stair climbing Packbot, Washington University in St Louis

High Lift, Low Drag Flippers (and tails)

Global warming and the search for alternative energy sources is driving the development of a new generation of wind turbine design. Engineers have traditionally plumped for simple, rigid lifting structures to deliver continuous, stable flow patterns. Nature however confounds conventional engineering theory by opting for bumpy flexible surfaces for whale flippers and dolphin tails. The bumpy leading edges of a humpback's flippers create vortices generating additional lift and improving the whale's maneuverability - useful in rounding up clouds of krill when feeding. For its part, the vertical motion of a dolphin's tail produces vortices, creating a jet in the dolphin's wake, and providing enormous thrust and swimming efficiency. Biomimetics is inspiring a new engineering approach to wind turbine designs that increase lift, reduce drag and delay stall.

Fish, F. E., Howle, L. E. and Murray, M. M. 2008. Hydrodynamic flow control in marine mammals;
Integrative and Comparative Biology 211: 1859-1867.   Image: 1. Dolphin, E. Paterson, 2. Large vortices forming behind leading edge, E. Paterson

Shakespear Done Elephants Wrong

Elephants it seems have been done an injustice. For centuries, writers such as Shakespeare have described the noble pachyderm as perambulating on stiff, pillar like legs. Not any more. Thanks to a team lead by John Hutchinson from the Royal Veterinary College, London we now know elephants enjoy significant movement in their  shoulders, hips, knees and elbow joints, although disappointingly, their ankles proved to be springy rather than flexible. Taking a lead out of Hollywood's bag of tricks, the team borrowed a couple of elephant from Colchester and Whipsnade Zoos, ranging from babies through to big mommas, dotted their legs with balls covered in infrared reflective tape, before coaxing the elephants to run (more or less) in front of a battery of infrared cameras. The test animals recorded speeds ranging from 0.62 m/s to a respectable 4.92 m/s. Keen to pit the pride of England against the world's best, the team popped over to Thailand to test the legendary Thai 'racing' elephants. The elite elephants easily whipped their UK opposition, recording a giddy 6.8 m/s! Having analyzed the stop action motion from the film, the team found elephants operate at almost the maximum of the mobility range, placing them somewhere near a trotting horse for mobility. So there Mr. Shakespeare - now you know!

PS. The hardest part of the project was keeping the baby elephants from pulling the infrared markers for the high speed cameras off the adults. The little buggers kept tugging them off with their trunks!  http://jeb.biologists.org/cgi/content/abstract/211/17/2735   Image: Asian elephant studded with infrared markers for the hgih speed cameras, Royal Veterinary College, London

Robot Life

That mechanical shark in Jaws had better be looking over its shoulder - Robofish is not far behind. The term 'robot' paints a wide canvass these days. Underwater robots have rarely been truly independent. They're usually tied to a parent ship or satellite communication system in order to receive their constant stream of directions. Not anymore. A University of Washington researcher inspired by the way schooling fish behave has built three ocean going robot fish able to communicate with each other. Roughly the size of a good salmon, Robofish use fins rather propellers and communicate with each other underwater using wireless. Now sending information underwater over long distances requires a lot of power - more than Robofish's batteries pack. Instead, Robofish swap instructions using sonar pulses - pressure waves. Even though the surrounding water interferes with the transmissions, Robofish's biomimicery based programming enables them to perform basic maneuvers based in concert with each other.

As anyone who has seen me walking home from a long, long Dubai brunch can attest, human walking is basically a controlled forward fall (or in my case, not-so-controlled!) forwards. Earlier this year I featured a snippet on Cornell's walking robot. Their robot set a long-distance walking record, marching resolutely around an indoor track. Across the other side of the world, Delft University of Technology has been doing some interesting work on walking robots for years. Now one of their researchers has received his PhD for his work in creating a way to measure the stability factor in how people work. Not content with a theoretical model, he demonstrated his model by building the world's most advanced walking robot 'Flame'. Flame is different to industrial robots in that it mimics the fluid, energy-efficient motion of a human walk. Flame achieves this thanks to seven motors, a balancing organ, some high spec algorithms and a pair of neat robotic ankles, making Flame the most advanced 'walking' robot in the world.

PS. The University of Washington's 'Seaglider' will be manufactured commercially after the University signed a production agreement with iRobot. 'Seaglider' is an ocean going sub-sea robot with an operating depth of 3,300 feet that currently holds the world record for autonomous underwater operation. 

http://uwnews.org/article.asp?articleID=42371   http://www.tudelft.nl/live/pagina.jsp?id=f58fa261-f359-4d83-81ce-78bc182750ea&lang=en   http://uwnews.org/article.asp?articleID=42437   Image: Fin-propelled Robofish, University of Washington, 2. Kristi Morgansen using a remote controller to direct Robofish, University of Washington, 3. Flame, Delft University of Technology, 4. Seaglider performing in the pool, University of Washington, 5. Seaglider, University of Washington

Bio Inspired Engineering #4

The future of computing lies with ultra high speed optical computers running on light in the form of photons. At the heart of these futuristic devices to function lies an exotic material able to manipulate visible light. Conventional science has failed miserably to develop photonic crystals.  Where to look? Nature came to the rescue in the form of the iridescent green scales of the Lamprocyphus augustus, an inch long Brazilian weevil. The weevil's chitin scales enjoy unique properties. Each scale is comprised of 200 individual chitin elements each with a diamond crystalline structure oriented in a different direction reflecting an individual wavelength of green light. The end result is a composite image our eye interprets as a very fetching iridescent green. Another example of where science fails nature triumphs! Now the only thing left to do is establish why a weevil needs such a distinctive colouration.

While medical science typically sees muscles as simply electric motors, there is a growing belief that muscles actually operate more like springs, storing energy and rapidly releasing it to generate force. Inspired by a toad's ability to snatch insects on the fly with its rapid action tongue, Northern Arizona researcher Kiisa Nishikawa is pioneering a new neuromuscular model. When it catches that juicy fly, a toad actually shortens the muscles in its lower jaw, then opens its jaws to unload the force stored in its tingue. In the process, the toad's jaw muscles produces loads greater than 700 times its own weight while an electric motor struggles to generate one-third of its weight! Figuring out how nature designed the toad and chameleon has implications for anything that moves and will contribute to new designs for electric motors and treatments for neuromuscular diseases such as Parkinson's.   

http://unews.utah.edu/p/?r=050908-7   http://www.onlinepressroom.net/nau/   Image: 1. Brazil's Lamprocyphus augustus weevil, Jeremy Galusha, University of Utah, 2. Professor Kiisa Nishikawa with cane toad from Suriname, Danielle Borth

Sailing the Briny Deep

Poor Ferdinand Magellan! You'd think having captained the first circumnavigation of the Earth (1519-22) discovering Guam and reaching The Philippines in the process, he would be forgiven for overshooting Indonesia's Spice islands by a mere 1,500 miles! Now through a combination of computer modeling and historical data, two researchers have fingered El Nino as the invisible hand guiding Magellan's voyage of discovery. The researchers hypothesised Magellan sailed around Cape Horn and into the remnants of an El Nino event. While the drought typically associated with El Nino events may have devastated island food supplies prompting Magellan to sail north, its prevailing northerly winds and current, combined with benign weather made for easy sailing. If correct, this would be the earliest record of an El Nino climate event.

Still on things nautical, a former MIT undergraduate student took time out from her dual majors in nuclear and mechanical engineering to mess about with a replica of the large ocean going rafts which plied the seas between Chile and western Mexico over a thousand years ago. A strong pre-Columbian connection between the Andean and Mesoamerican civilizations emerged from analysis of the metallurgy used in producing silver and copper goods, as well as the trade in the prized spondylus shell beads. Now detailed computer analysis of the replica's seaworthiness, handling and cargo capacity demonstrate the feasibility of ancient oceanic trade routes. At 10-30 tons capacity, the rafts could make the six to eight week voyage during the trade wind window (the rafts couldn't sail again the wind). The MIT paper is the first to use advanced marine engineering analysis to identify the design parameters of ancient water craft - quite a stretch from nuclear engineering!

http://news.ncsu.edu/news/2008/05/wmsfitzpatrickmagellan.php   http://web.mit.edu/newsoffice/2008/raft-tt0319.html   Image: 1. Ferdinand Magellan, Wikipedia, 2. Magellan's voyage of discovery, www.oceansatlas.com 2. MIT students aboard the replica raft, Dinna Coveney, MIT, 3. Early 17th Century sketch of native raft, Joris von Spilbergen

Engineering Our Future

Size of often the engineers enemy, particularly in the emerging 'wireless body area network' biosensor technology sector. Too big and the sensors are uncomfortable to wear, too small and the sensors lack adequate battery life or signal strength. Engineers at Queen's University Belfast have developed a new antenna that skirts these obstacles. The technology exploits the 'creeping wave' effect. When a signal is broadcast from an on-body sensor, most of the signal strength is either absorbed by the body or radiated outwards. The remainder (the creeping wave) hugs the surface of the skin. The novel antenna is 50 times more efficient than its predecessors, allowing its thickness to drop from 34mm to under 5mm. The signal is simply transmitted to a control unit on the body, where it can be accessed by doctors over the internet or by mobile phone!

Serendipity made it into space in April when a Finnish design for a solar wind sail went from design to prototype. Born from the Finnish Meteorological Institute's research into how the solar wind interacts with the planets and their atmosphere, the design might just revolutionize space exploration. The solar sail traps the continuous gentle pressure of the solar wind to provide thrust. The design features long metallic tethers and a solar powered electron gun to maintain the tethers positive charged, maintaining the sail's shape. Prototyping the new solar sail hinged on successfully developing a new technique for ultrasonic welding to bond the thin metal wire comprising micrometeoroid-resistant tethers.

http://www.eurekalert.org/pub_releases/2008-05/eaps-iam051408.php   http://www.fmi.fi/news/index.html?Id=1208243495.html   Image: 1. Wearable antennas being tested, Engineering and Physical Sciences research Council, 2. Electric sail design, Antonin Halas, Finnish Meteorological Institute

Hand (and Eye) of Fate

There is nothing like a war to stimulate new ideas and technology developments and as usual, the Germans have been beavering away on the engineering front. Two interesting examples came across my desk last week. First we have yet another artificial hand - the Fluidhand. Developed in Karlsruhe, this artificial hand employs biomimickery to simulate the human hand's moveable finger joints. To flex each joint, elastic chambers within the finger are pumped up using miniature hydraulics, enabling the index and middle fingers and the thumb to move independently. It uses a similar biological engineering approach to the one powering spider legs. Fluidhand provides a better grip than other prosthetic hands thanks to its large contact area and soft finish. Thanks to its programmable grip, power feedback and easily adjustable controls, it can hold a credit card, use a keyboard and lift a 20kg bag. Unfortunately, it's not a prototype only and not in production.

Our other example of Germanic ingenuity is the 'Kolbi Cordless'. I know that sounds like a sewing machine or an electric drill but in real life it's a nifty three-dimensional imaging camera. Developed by the Fraunhofer Institute for Applied Optics and Precision Engineering IOF in Jena, the mighty 'Cordless' comprises two camera with a projector mounted between them. It works by projecting a pattern of stripes one the object being imaged. Recording the disruption to the stripes allows the geometry of the object to be imaged. While other 3-D devices exist, they are twice the size and too heavy to be really portable. The breakthrough came through substituting light emitting diodes for the then-standard halogen light in the 'Cordless's' projector. This enabled significant reductions in size and weight, making the 'Cordless' cordless operational possible. The 'Kolbi Cordless' will image everything from tire tracks in a muddy road (useful for frustrated CSI types) to the human face.

http://www.klinikum.uni-heidelberg.de/ShowSingleNews.7870.0.html?&cHash=9e3ce13ea3&tx_ttnews%5BbackPid%5D=7868&tx_ttnews%5BpS%5D=1209114667&tx_ttnews%5Btt_news%5D=3730   http://www.fraunhofer.de/EN/press/pi/2008/04/ResearchNews42008Topic3.jsp   Image: 1. Fluidhand, Orthopedic University Hospital in Heidelberg, 2. A 3-D sensor, Fraunhofer IOF, 3. Three dimensional image of a ar tyre track,Fraunhofer IOF

When Soap Bubbles Go Bad

Curiosity sets us exploring the most unlikely phenomena. No where is this more so than at the Centre National de la Recherche Scientifique (CNRS). Their boffins study our atmosphere using, amongst other models, soap bubbles! It seems soap bubbles make very good atmospheric models indeed! Like the Earth's atmosphere, soap bubbles have a very thin film in relation to their diameter. Now when the pointy heads took a quietly unassuming soap bubble, heated it in the middle and cooled it at the ends, they created a single vortex - a cyclone in perfect miniature. What they saw then surprised them. The movement of the vortex behaved in exactly the same random way as recent hurricanes. For the first time, researchers could understand the random factor that associated with a vortex's movements. Is this useful? Well, scientists may get better at predicting the behaviour of hurricanes and cyclones and they do have the pleasure of blowing some beautiful bubbles while they're doing it!

http://www.cnrs.fr/index.html   Image: Thermal convection bubble with large vortex in the upper part of the picture, American Physical Society