Swimming Robot Makes Waves At Bath.

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ScienceDaily (Sep. 25, 2009) — Researchers at the University of Bath have used nature for inspiration in designing a new type of swimming robot which could bring a breakthrough in submersible technology.

Conventional submarine robots are powered by propellers that are heavy, inefficient and can get tangled in weeds.
In contrast ‘Gymnobot', created by researchers from the Ocean Technologies Lab in the University's Department of Mechanical Engineering, is powered by a fin that runs the length of the underside of its rigid body; this undulates to make a wave in the water which propels the robot forwards.
The design, inspired by the Amazonian knifefish, is thought to be more energy efficient than conventional propellers and allows the robot to navigate shallow water near the sea shore.
Gymnobot could be used to film and study the diverse marine life near the seashore, where conventional submersible robots would have difficulty manoeuvring due to the shallow water with its complex rocky environment and plants that can tangle a propeller.
Dr William Megill, Lecturer in Biomimetics at the University of Bath, explained: "The knifefish has a ventral fin that runs the length of its body and makes a wave in the water that enables it to easily swim backwards or forwards in the water.
"Gymnobot mimics this fin and creates a wave in the water that drives it forwards. This form of propulsion is potentially much more efficient than a conventional propeller and is easier to control in shallow water near the shore."
Keri Collins, a postgraduate student who developed the Gymnobot as part of her PhD, added: "We hope to observe how the water flows around the fin in later stages of the project. In particular we want to look at the creation and development of vortices around the fin.
"Some fish create vortices when flicking their tails one way but then destroy them when their tails flick back the other way. By destroying the vortex they are effectively re-using the energy in that swirling bit of water. The less energy left in the wake when the fish has passed, the less energy is wasted.
"It will be particularly interesting to see how thrust is affected by changing the wave of the fin from a constant amplitude to one that is tapered at one end."
The lab was recently awarded a grant to work with six other European institutions to create a similar robot that reacts to water flow and is able to swim against currents.
In addition to studying biodiversity near the shore and in fast-flowing rivers, robots like Gymnobot could also be used for detecting pollution in the environment or for inspecting structures such as oil rigs.
The project was funded by BMT Defence Services and the Engineering & Physical Sciences Research Council.
Adapted from materials provided by University of Bath, via AlphaGalileo.

The Interoperable Telesurgical Protocol.

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ScienceDaily (Sep. 18, 2009) — Using a new software protocol called the Interoperable Telesurgical Protocol, nine research teams from universities and research institutes around the world recently collaborated on the first successful demonstration of multiple biomedical robots operated from different locations in the U.S., Europe, and Asia. SRI International operated its M7 surgical robot for this demonstration.

In a 24-hour period, each participating group connected over the Internet and controlled robots at different locations. The tests performed demonstrated how a wide variety of robot and controller designs can seamlessly interoperate, allowing researchers to work together easily and more efficiently. In addition, the demonstration evaluated the feasibility of robotic manipulation from multiple sites, and was conducted to measure time and performance for evaluating laparoscopic surgical skills.
New Interoperable Telesurgical Protocol The new protocol was cooperatively developed by the University of Washington and SRI International, to standardize the way remotely operated robots are managed over the Internet.
"Although many telemanipulation systems have common features, there is currently no accepted protocol for connecting these systems," said SRI's Tom Low. "We hope this new protocol serves as a starting point for the discussion and development of a robust and practical Internet-type standard that supports the interoperability of future robotic systems."
The protocol will allow engineers and designers that usually develop technologies independently, to work collaboratively, determine which designs work best, encourage widespread adoption of the new communications protocol, and help robotics research to evolve more rapidly. Early adoption of this protocol internationally will encourage robotic systems to be developed with interoperability in mind, and avoid future incompatibilities.
"We're very pleased with the success of the event in which almost all of the possible connections between operator stations and remote robots were successful. We were particularly excited that novel elements such as a simulated robot and an exoskeleton controller worked smoothly with the other remote manipulation systems," said Professor Blake Hannaford of the University of Washington.
The demonstration included the following organizations:
SRI International, Menlo Park, Calif., USA
University of Washington Biorobotics Lab (BRL), Seattle, Washington, USA
University of California at Santa Cruz (UCSC), Bionics Lab, Santa Cruz, Calif., USA
iMedSim, Interactive Medical Simulation Laboratory, Rensselaer Polytechnic Institute, Troy, New York, USA
Korea University of Technology (KUT) BioRobotics Lab, Cheonan, South Chungcheong, South Korea
Imperial College London (ICL), London, England
Johns Hopkins University (JHU), Baltimore, Maryland, USA
Technische Universität München (TUM), Munich, Germany
Tokyo Institute of Technology (TOK), Tokyo, Japan
For more information regarding availability of the Interoperable Telesurgical Protocol, please visit: http://brl.ee.washington.edu/Research_Active/Interoperability/index.php/Main_Page
Adapted from materials provided by SRI International.

Silicon With Afterburners: New Process Could Be Boon To Electronics Manufacturer

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ScienceDaily (July 24, 2009) — Scientists at Rice University and North Carolina State University have found a method of attaching molecules to semiconducting silicon that may help manufacturers reach beyond the current limits of Moore's Law as they make microprocessors both smaller and more powerful.

Moore's Law, suggested by Intel co-founder Gordon Moore in 1965, said the number of transistors that can be placed on an integrated circuit doubles about every two years. But even Moore has said the law cannot be sustained indefinitely.
The challenge is to get past the limits of doping, a process that has been essential to creating the silicon substrate that is at the heart of all modern integrated circuits, said James Tour, Rice's Chao Professor of Chemistry and professor of mechanical engineering and materials science and of computer science.
Doping introduces impurities into pure crystalline silicon as a way of tuning microscopic circuits to a particular need, and it's been effective so far even in concentrations as small as one atom of boron, arsenic or phosphorus per 100 million of silicon.
But as manufacturers pack more transistors onto integrated circuits by making the circuits ever smaller, doping gets problematic.
"When silicon gets really small, down to the nanoscale, you get structures that essentially have very little volume," Tour said. "You have to put dopant atoms in silicon for it to work as a semiconductor, but now, devices are so small you get inhomogeneities. You may have a few more dopant atoms in this device than in that one, so the irregularities between them become profound."
Manufacturers who put billions of devices on a single chip need them all to work the same way, but that becomes more difficult with the size of a state-of-the-art circuit at 45 nanometers wide -- a human hair is about 100,000 nanometers wide -- and smaller ones on the way.
The paper suggests that monolayer molecular grafting -- basically, attaching molecules to the surface of the silicon rather than mixing them in -- essentially serves the same function as doping, but works better at the nanometer scale. "We call it silicon with afterburners," Tour said. "We're putting an even layer of molecules on the surface. These are not doping in the same way traditional dopants do, but they're effectively doing the same thing."
Tour said years of research into molecular computing with an eye toward replacing silicon has yielded little fruit. "It's hard to compete with something that has trillions of dollars and millions of person-years invested into it. So we decided it would be good to complement silicon, rather than try to supplant it."
He anticipates wide industry interest in the process, in which carbon molecules could be bonded with silicon either through a chemical bath or evaporation. "This is a nice entry point for molecules into the silicon industry. We can go to a manufacturer and say, 'Let us make your fabrication line work for you longer. Let us complement what you have.'
"This gives the Intels and the Microns and the Samsungs of the world another tool to try, and I guarantee you they'll be trying this."
Journal reference:
He et al. Controllable Molecular Modulation of Conductivity in Silicon-Based Devices. Journal of the American Chemical Society, 2009; 131 (29): 10023 DOI: 10.1021/ja9002537
Adapted from materials provided by Rice University.

Music Is The Engine Of New Lab-on-a-chip Device

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ScienceDaily (July 23, 2009) — Music, rather than electromechanical valves, can drive experimental samples through a lab-on-a-chip in a new system developed at the University of Michigan. This development could significantly simplify the process of conducting experiments in microfluidic devices.

A paper on the research will be published online in the Proceedings of the National Academy of Sciences the week of July 20.
A lab-on-a-chip, or microfluidic device, integrates multiple laboratory functions onto one chip just millimeters or centimeters in size. The devices allow researchers to experiment on tiny sample sizes, and also to simultaneously perform multiple experiments on the same material. There is hope that they could lead to instant home tests for illnesses, food contaminants and toxic gases, among other advances.
To do an experiment in a microfluidic device today, researchers often use dozens of air hoses, valves and electrical connections between the chip and a computer to move, mix and split pin-prick drops of fluid in the device's microscopic channels and divots.
"You quickly lose the advantage of a small microfluidic system," said Mark Burns, professor and chair of the Department of Chemical Engineering and a professor in the Department of Biomedical Engineering.
"You'd really like to see something the size of an iPhone that you could sneeze onto and it would tell you if you have the flu. What hasn't been developed for such a small system is the pneumatics—the mechanisms for moving chemicals and samples around on the device."
The U-M researchers use sound waves to drive a unique pneumatic system that does not require electromechanical valves. Instead, musical notes produce the air pressure to control droplets in the device. The U-M system requires only one "off-chip" connection.
"This system is a lot like fiberoptics, or cable television. Nobody's dragging 200 separate wires all over your house to power all those channels," Burns said. "There's one cable signal that gets decoded."
The system developed by Burns, chemical engineering doctoral student Sean Langelier, and their collaborators replaces these air hoses, valves and electrical connections with what are called resonance cavities. The resonance cavities are tubes of specific lengths that amplify particular musical notes.
These cavities are connected on one end to channels in the microfluidic device, and on the other end to a speaker, which is connected to a computer. The computer generates the notes, or chords. The resonance cavities amplify those notes and the sound waves push air through a hole in the resonance cavity to their assigned channel. The air then nudges the droplets in the microfluidic device along.
"Each resonance cavity on the device is designed to amplify a specific tone and turn it into a useful pressure," Langelier said. "If I play one note, one droplet moves. If I play a three-note chord, three move, and so on. And because the cavities don't communicate with each other, I can vary the strength of the individual notes within the chords to move a given drop faster or slower."
Burns describes the set-up as the reverse of a bell choir. Rather than ringing a bell to create sound waves in the air, which are heard as music, this system uses music to create sound waves in the device, which in turn, move the experimental droplets.
"I think this is a very clever system," Burns said. "It's a way to make the connections between the microfluidic world and the real world much simpler."
The new system is still external to the chip, but the researchers are working to make it smaller and incorporate it on a microfluidic device. That would be a step closer to a smartphone-sized home flu test.
The paper is called, "Acoustically-driven programmable liquid motion using resonance cavities." Other authors are U-M chemical engineering graduate students Dustin Chang and Ramsey Zeitoun. The research is funded by the National Institutes of Health and the National Science Foundation. The University is pursuing patent protection for the intellectual property.
Adapted from materials provided by University of Michigan.

Cell Phones Turned Into Fluorescent Microscopes

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ScienceDaily (July 22, 2009) — Researchers at the University of California, Berkeley, are proving that a camera phone can capture far more than photos of people or pets at play. They have now developed a cell phone microscope, or CellScope, that not only takes color images of malaria parasites, but of tuberculosis bacteria labeled with fluorescent markers.

The prototype CellScope, described in the journal PLoS One, moves a major step forward in taking clinical microscopy out of specialized laboratories and into field settings for disease screening and diagnoses.
"The same regions of the world that lack access to adequate health facilities are, paradoxically, well-served by mobile phone networks," said Dan Fletcher, UC Berkeley associate professor of bioengineering and head of the research team developing the CellScope. "We can take advantage of these mobile networks to bring low-cost, easy-to-use lab equipment out to more remote settings."
The engineers attached compact microscope lenses to a holder fitted to a cell phone. Using samples of infected blood and sputum, the researchers were able to use the camera phone to capture bright field images of Plasmodium falciparum, the parasite that causes malaria in humans, and sickle-shaped red blood cells. They were also able to take fluorescent images of Mycobacterium tuberculosis, the bacterial culprit that causes TB in humans. Moreover, the researchers showed that the TB bacteria could be automatically counted using image analysis software.
"The images can either be analyzed on site or wirelessly transmitted to clinical centers for remote diagnosis," said David Breslauer, co-lead author of the study and a graduate student in the UC San Francisco/UC Berkeley Bioengineering Graduate Group. "The system could be used to help provide early warning of outbreaks by shortening the time needed to screen, diagnose and treat infectious diseases."
The engineers had previously shown that a portable microscope mounted on a mobile phone could be used for bright field microscopy, which uses simple white light - such as from a bulb or sunlight - to illuminate samples. The latest development adds to the repertoire fluorescent microscopy, in which a special dye emits a specific fluorescent wavelength to tag a target - such as a parasite, bacteria or cell - in the sample.
"Fluorescence microscopy requires more equipment - such as filters and special lighting - than a standard light microscope, which makes them more expensive," said Fletcher. "In this paper we've shown that the whole fluorescence system can be constructed on a cell phone using the existing camera and relatively inexpensive components."
The researchers used filters to block out background light and to restrict the light source, a simple light-emitting diode (LED), to the 460 nanometer wavelength necessary to excite the green fluorescent dye in the TB-infected blood. Using an off-the-shelf phone with a 3.2 megapixel camera, they were able to achieve a spatial resolution of 1.2 micrometers. In comparison, a human red blood cell is about 7 micrometers in diameter.
"LEDs are dramatically more powerful now than they were just a few years ago, and they are only getting better and cheaper," said Fletcher. "We had to disabuse ourselves of the notion that we needed to spend many thousands on a mercury arc lamp and high-sensitivity camera to get a meaningful image. We found that a high-powered LED - which retails for just a few dollars - coupled with a typical camera phone could produce a clinical quality image sufficient for our goal of detecting in a field setting some of the most common diseases in the developing world."
The researchers pointed out that while fluorescent microscopes include additional parts, less training is needed to interpret fluorescent images. Instead of sorting out pathogens from normal cells in the images from standard light microscopes, health workers simply need to look for something the right size and shape to light up on the screen.
"Viewing fluorescent images is a bit like looking at stars at night," said Breslauer. "The bright green fluorescent light stands out clearly from the dark background. It's this contrast in fluorescent imaging that allowed us to use standard computer algorithms to analyze the sample containing TB bacteria."
Breslauer added that these software programs can be easily installed onto a typical cell phone, turning the mobile phone into a self-contained field lab and a "good platform for epidemiological monitoring."
While the CellScope is particularly valuable in resource-poor countries, Fletcher noted that it may have a place in this country's health care system, famously plagued with cost overruns.
"A CellScope device with fluorescence could potentially be used by patients undergoing chemotherapy who need to get regular blood counts," said Fletcher. "The patient could transmit from home the image or analyzed data to a health care professional, reducing the number of clinic visits necessary."
The CellScope developers have even been approached by experts in agriculture interested in using it to help diagnose diseases in crops. Instead of sending in a leaf sample to a lab for diagnosis, farmers could upload an image of the diseased leaf for analysis.
The researchers are currently developing more robust prototypes of the CellScope in preparation for further field testing.
Other researchers on the team include Robi Maamari, a UC Berkeley research associate in bioengineering and co-lead author of the study; Neil Switz, a graduate student in UC Berkeley's Biophysics Graduate Group; and Wilbur Lam, a UC Berkeley post-doctoral fellow in bioengineering and a UCSF pediatric hematologist.
Funding for the CellScope project comes from the Center for Information Technology Research in the Interest of Society (CITRIS) and the Blum Center for Developing Economies, both at UC Berkeley, and from Microsoft Research, Intel and the Vodafone Americas Foundation.
Journal reference:
David N. Breslauer et al. Mobile Phone Based Clinical Microscopy for Global Health Applications. PLoS One, July 22, 2009 DOI: 10.1371/journal.pone.0006320
Adapted from materials provided by University of California - Berkeley.

Electronic Nose Created To Detect Skin Vapors

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ScienceDaily (July 21, 2009) — A team of researchers from the Yale University (United States) and a Spanish company have developed a system to detect the vapours emitted by human skin in real time. The scientists think that these substances, essentially made up of fatty acids, are what attract mosquitoes and enable dogs to identify their owners.

"The spectrum of the vapours emitted by human skin is dominated by fatty acids. These substances are not very volatile, but we have developed an 'electronic nose' able to detect them", Juan Fernández de la Mora, of the Department of Mechanical Engineering at Yale University (United States) and co-author of a study recently published in the Journal of the American Society for Mass Spectrometry, says.
The system, created at the Boecillo Technology Park in Valladolid, works by ionising the vapours with an electrospray (a cloud of electrically-charged drops), and later analysing these using mass spectrometry. This technique can be used to identify many of the vapour compounds emitted by a hand, for example.
"The great novelty of this study is that, despite the almost non-existent volatility of fatty acids, which have chains of up to 18 carbon atoms, the electronic nose is so sensitive that it can detect them instantaneously", says Fernández de la Mora. The results show that the volatile compounds given off by the skin are primarily fatty acids, although there are also others such as lactic acid and pyruvic acid.
The researcher stresses that the great chemical wealth of fatty acids, made up of hundreds of different molecules, "is well known, and seems to prove the hypothesis that these are the key substances that enable dogs to identify people". The enormous range of vapours emitted by human skin and breath may not only enable dogs to recognise their owners, but also help mosquitoes to locate their hosts, according to several studies.
World record for detecting explosives
Aside from identifying people from their skin vapours, another of the important applications of the new system is that it is able to detect tiny amounts of explosives. The system can "smell" levels below a few parts per trillion, and has been able to set a world sensitivity record at "2x10-14 atmospheres of partial pressure of TNT (the explosive trinitrotoluene)".
The "father" of ionisation using the mass spectrometry electrospray is Professor John B. Fenn, who is currently a researcher at the University of Virginia (United States), and in 2002 won the Nobel Prize in Chemistry for using this technique in the analysis of proteins.
Journal references:
Pablo Martínez Lozano y Juan Fernández de la Mora. Online Detection of Human Skin Vapors. Journal of the American Society for Mass Spectrometry, 20 (6): 1060-1063, 2009
Martínez-Lozano et al. Secondary Electrospray Ionization (SESI) of Ambient Vapors for Explosive Detection at Concentrations Below Parts Per Trillion. Journal of the American Society for Mass Spectrometry, 2009; 20 (2): 287 DOI: 10.1016/j.jasms.2008.10.006
Adapted from materials provided by FECYT - Spanish Foundation for Science and Technology, via EurekAlert!, a service of AAAS.

Human-like Vision Lets Robots Navigate Naturally

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ScienceDaily (July 17, 2009) — A robotic vision system that mimics key visual functions of the human brain promises to let robots manoeuvre quickly and safely through cluttered environments, and to help guide the visually impaired.

It’s something any toddler can do – cross a cluttered room to find a toy.
It's also one of those seemingly trivial skills that have proved to be extremely hard for computers to master. Analysing shifting and often-ambiguous visual data to detect objects and separate their movement from one’s own has turned out to be an intensely challenging artificial intelligence problem.
Three years ago, researchers at the European-funded research consortium Decisions in Motion (http://www.decisionsinmotion.org/) decided to look to nature for insights into this challenge.
In a rare collaboration, neuro- and cognitive scientists studied how the visual systems of advanced mammals, primates and people work, while computer scientists and roboticists incorporated their findings into neural networks and mobile robots.
The approach paid off. Decisions in Motion has already built and demonstrated a robot that can zip across a crowded room guided only by what it “sees” through its twin video cameras, and are hard at work on a head-mounted system to help visually impaired people get around.
“Until now, the algorithms that have been used are quite slow and their decisions are not reliable enough to be useful,” says project coordinator Mark Greenlee. “Our approach allowed us to build algorithms that can do this on the fly, that can make all these decisions within a few milliseconds using conventional hardware.”
How do we see movement?
The Decisions in Motion researchers used a wide variety of techniques to learn more about how the brain processes visual information, especially information about movement.
These included recording individual neurons and groups of neurons firing in response to movement signals, functional magnetic resonance imaging to track the moment-by-moment interactions between different brain areas as people performed visual tasks, and neuropsychological studies of people with visual processing problems.
The researchers hoped to learn more about how the visual system scans the environment, detects objects, discerns movement, distinguishes between the independent movement of objects and the organism’s own movements, and plans and controls motion towards a goal.
One of their most interesting discoveries was that the primate brain does not just detect and track a moving object; it actually predicts where the object will go.
“When an object moves through a scene, you get a wave of activity as the brain anticipates its trajectory,” says Greenlee. “It’s like feedback signals flowing from the higher areas in the visual cortex back to neurons in the primary visual cortex to give them a sense of what’s coming.”
Greenlee compares what an individual visual neuron sees to looking at the world through a peephole. Researchers have known for a long time that high-level processing is needed to build a coherent picture out of a myriad of those tiny glimpses. What's new is the importance of strong anticipatory feedback for perceiving and processing motion.
“This proved to be quite critical for the Decisions in Motion project,” Greenlee says. “It solves what is called the ‘aperture problem’, the problem of the neurons in the primary visual cortex looking through those little peepholes.”
Building a better robotic brain
Armed with a better understanding of how the human brain deals with movement, the project’s computer scientists and roboticists went to work. Using off-the-shelf hardware, they built a neural network with three levels mimicking the brain’s primary, mid-level, and higher-level visual subsystems.
They used what they had learned about the flow of information between brain regions to control the flow of information within the robotic “brain”.
“It’s basically a neural network with certain biological characteristics,” says Greenlee. “The connectivity is dictated by the numbers we have from our physiological studies.”
The computerised brain controls the behaviour of a wheeled robotic platform supporting a moveable head and eyes, in real time. It directs the head and eyes where to look, tracks its own movement, identifies objects, determines if they are moving independently, and directs the platform to speed up, slow down and turn left or right.
Greenlee and his colleagues were intrigued when the robot found its way to its first target – a teddy bear – just like a person would, speeding by objects that were at a safe distance, but passing nearby obstacles at a slower pace.
”That was very exciting,” Greenlee says. “We didn’t program it in – it popped out of the algorithm.”
In addition to improved guidance systems for robots, the consortium envisions a lightweight system that could be worn like eyeglasses by visually or cognitively impaired people to boost their mobility. One of the consortium partners, Cambridge Research Systems, is developing a commercial version of this, called VisGuide.
Decisions in Motion received funding from the ICT strand of the EU’s Sixth Framework Programme for research. The project’s work was featured in a video by the New Scientist in February this year.
Adapted from materials provided by ICT Results.