A breakthrough in Australia draws tractor beams closer to reality
October 23, 2014
A tractor beam that works like the technology depicted in science fiction movies would have endless applications beyond luring cocksure smugglers and their furry alien friends into moon-sized space stations. Physicists and laser experts have labored for years to produce a beam of light capable of attracting and repelling matter, and are still stumped when it comes to scaling the technology for wider applications. A recent discovery by laser experts at the Australian National University may be the breakthrough that sci-fi fans and scientists alike have been searching for.
Star Wars gets real
Physicists at the Australian National University have developed a working tractor beam utilizing a single, hollow laser beam with bright edges and a dark center, according to the ANU website. Researchers have been able to move particles measuring 0.20 millimeter in diameter over a distance of up to 20 centimeters. This distance easily outpaces that of previous tractor beam experiments. Older tractor beam prototypes were only able to move particles by a fraction of the distance achieved by ANU's device, and researchers believe that the tractor beam could move particles over even longer distances if given a larger lab space. The breakthrough is so significant that Professor Wieslaw Krolikowski deemed the successful experiment as "a kind of holy grail for laser physicists."
The tractor beam designed by the Australian National University works by laser heating the particle's surface and surrounding air. The surfaces of particles trapped in the beam heats up as they are bombarded by laser, absorbing energy and producing hot spots on the surface of the particle. Air molecules, trapped in the dark center of the laser beam, collide with the heated particle surface before rebounding in another direction. This interaction impresses a recoil force on the particle, pushing it in the opposite direction of the fleeing air particles.
ANU's technique is also impressive because it employs a single laser beam to attract and repel objects. Laser physicists at the Australian National University are able to carefully control the polarization of the laser beam, subsequently manipulating where hotspots will appear on the particle being heated by the beam. The team can switch between polarization on the fly, and this flexibility allows the university's tractor beam go between pulling and pushing with ease.
An array of possibilities
Fully functional tractor beam technology would have nearly endless applications in a wide variety of industries. CNET pointed out that the technology could be used to improve pollution collection and help clean up the atmosphere. Alternatively, scientists could use the device to collect samples of dangerous particles from a safe distance. The technology has potential for advancing medical science as well. The New Yorker noted that such a device could improve the effectiveness of medicinal treatment by holding a targeted drug delivery systems in place within the body. With luck, the technology will one day assist astronauts to manipulate objects in outer space.
Recent tractor beam discoveries
NASA took up the challenge of designing a working tractor beam in 2011. The organization invested $100,000 to investigate three methods that showed promise in developing tractor beam technology that could collect and transport items directly to a containment unit. The tool would be a priceless addition to any planet rover or sample-collecting satellite.
The first approach NASA researched was the use of two beams of light to produce an optical vortex. The approach utilized a set of two lasers tuned to different intensities. Scientists were able to move particles caught in the overlap between the two lasers. Another strategy took advantage of electromagnetic properties to drive objects along a light-beam, and this approach showed promise for use in atmosphereless space. NASA also tested a laser beam that moves matter by emitting electric and magnetic fields in the object's path.
The University of St. Andrews and the Institute of Instruments later made a tractor beam breakthrough of their own as recently as January of 2013, according to the school's website. The technique developed by the two organizations generates a unique optical field that manipulates light's radiation pressure on matter trapped in the beam. Light photos naturally exert positive pressure on miniscule matter particles, guiding tiny particles along with the flow of light. The team's research revealed that it is possible to reverse light's radiation pressure under certain conditions.
These conditions are unique to each object, controlled by the particle's size and chemical properties. Scientists also observed that certain conditions influence particles into a configuration that actually reinforces the strength of the laser. A combination of this research and the new device developed by the Australian National University could transform tractor beam technology from bright idea to mainstream.
Rapid advances in 3-D bioprinting rewrite the script for surgery
October 20, 2014
Scientists have had access to methods for creating organs using 3-D printing technology for several years, and the technology is finally beginning to reach its initial stages of maturity. One notable breakthrough that could act as a turning point for the bioprinting community is the recent development of a cost-effective bioprinter by biotech company BioBots and the University of Pennsylvania, according to 3DPrint. The device will be able to put affordable 3-D bioprinting devices in the hands of researchers and non-scientists alike, and this expanded accessibility is bound to help drive innovation.
New technology controls research costs
Any research institution or amateur bioengineer will soon be able to beta test a device designed to print multiple forms of tissue for just $5,000, thanks to research lead by BioBots CEO Daniel Cabrera. The BioBots 3-D printer employs both U-V light and "Blue Light" to harden tissues as they are printed. The printer is able to switch between over a dozen types of tissue and non-organic scaffolding materials on the fly, greatly expanding the complexity of the organs the device can produce.
In addition to the 3-D bioprinter, BioBots will provide beta testers with several resources in an effort to support innovation by private health organizations and research universities. Those accepted into the beta test will also receive a one-year service agreement from BioBots, software resources and the ability the showcase any developments at BioBots' many scheduled appearances at several upcoming research conferences. Research institutions that are not accepted into the beta test will still be able to purchase the 3-D printer and its peripheral equipment for $25,000. BioBots also promises to provide testers with online channels for collaboration purposes. This widespread testing with the BioBots is sure to help to support current 3-D bioprinting research by cutting costs and streamlining the production of organic tissue.
3-D models provide tools for surgeons
One application where the new BioBots 3-D printer can have an immediate impact is the development of model organs for surgeons. Wired UK reported that surgeons at Kosair's Children's Hospital in Kentucky are utilizing 3-D printing technology to build organs based on the patient's affected tissue. The near-identical model of the heart can be used to give surgeons realistic, hands-on practice with a patient's organ's without performing invasive surgery. This priceless opportunity to simulate surgery's without risking the health of the patients will give surgeons worldwide a significant advantage in completing difficult surgeries once the technique is readily accessible. The price of the BioBots bioprinter will help to put this technique within reach for a larger number of health facilities.
Refining techniques to scale
Widespread access to BioBots' versatile 3-D printer could also help to drive the development of more accurate bioprinters that are closer to producing organs that seamlessly integrate into a patient's body. Modern 3-D bioprinting techniques have been used to create usable implants in orthopedic medicine, but the technology is still limited when it comes to producing functional organs that could be safely implanted into a patient.
Randy Haluck, a surgeon at Penn State Hershey Medical Center, recently offered perspective on the where current 3-D printing technology needs improvement at the school's Bio Life Sciences Future conference, says MedCity News. Haluck noted that the organs produced by current 3-D bioprinters "look more like the organs they're representing rather than function like them" and "need to be about 200 microns from a blood vessel." The BioBots 3-D printer, far cheaper than similar devices on the market that commonly cost as much as $250,000, will be instrumental in helping researchers to refine the 3-D bioprinting techniques and create functioning human organs.
Cutting-edge batteries can charge completely in minutes
October 17, 2014
Rechargeable lithium-ion batteries have become an integral part of everyday life. The innovative batteries can be found in smart phones, power drills, wheelchairs, digital camcorders, portable game consoles, consumer vehicles and space rovers. Lithium-ion batteries are used extensively despite key flaws, including their short life cycle and lengthy charge time, but a new breakthrough by researchers at Singapore's Nanyang Technological University may have helped to minimize these weaknesses. A team led by association professor Chen Xiaodong has invented a new lithium-ion battery that boasts a lifespan of two decades and can be charged to 70 percent in just two minutes.
Nanoparticles key to innovation
Integral to the discovery of quick-charging lithium-ion batteries was the development of a titanium oxide gel used to replace a lithium battery's graphite anode, according to CNET. The gel, comprised of titanium oxide nanoparticles, is able to bond with the battery's electrodes without the need for chemical additives. Eliminating this extra step from the chemical process allows the battery developed by NTU to charge substantially faster than traditional batteries. Professor Chen, who also invented the nanoparticle gel, is currently seeking a Proof-of-Concept grant to develop the new battery at industry scale, according to the Nanyang Technological University website.
Charged with potential
NTU's battery is expected to make its way to the market within two years. Not surprisingly, the innovation has already attracted interest from manufacturers - the list of potential applications for Chen's quick-charging battery is extensive. The discovery has even been praised by famed professor Rachid Yazami, co-developer of the very lithium-graphite anode technology that NTU's titanium dioxide gel was designed to replaced. The battery pioneer, who changed the face of battery design three decades ago, noted that the invention is key for the next generation of battery-powered cars.
CNET noted that the new batteries could allow electrical vehicles to theoretically charge 20 times less often than current litium-ion technology. The increased lifespan of the batteries would ease costs on consumers by requiring fewer and fewer battery replacements over the course of ownership. Reducing the need for replacement batteries will help to slow the production of waste materials as well. If NTU's new battery can address the major shortcomings of electric vehicles, then the invention may also be responsible for new advances in sustainable vehicle design.
Versatile titanium dioxide
Professor Chen's battery is just one of the many areas of research where scientists have found novel use for titanium dioxide nanoparticles. The chemical is cheaply acquired and easy to form into nanostructures, making factory-scale production of products like lithium-ion batteries feasible. Titanium dioxide nanoparticles are also especially adept at the absorption of various toxic chemicals, which makes the material ideal for several industrial and environmental solutions.
Plastic News reported that a team at Johnson Controls Inc. is currently studying the effectiveness of titanium oxide nanoparticles for the removal of volatile organic compounds from car interiors. Researchers hope to use a coating of titanium oxide nanoparticles to remove traces of chemicals used to seal and finish new car interiors. Overexposure to such chemicals can cause adverse health reactions, and manufacturers are required by the EPA to minimize emissions of VOCs.
The ability of titanium dioxide to purify waste materials may even be improved in the near future. Scientists at Tabriz University have found that producing titanium dioxide nanoparticles on a bed of montmorillonite produced a superior decontaminate particle, notes Nanotechnology Now. The composite nanoparticle displayed an even smaller diameter than normal titanium dioxide and was capable of removing 80 percent of test waste from a compromised water source.
New exoskeleton from Lockheed Martin exponentially improves worker productivity
October 15, 2014
Everyone has dreamed of having super powers, but for most of the history of humanity, attributes like x-ray vision or super-strength have been the stuff of comic books and Hollywood movies… until recently. Lockheed Martin, one of the innovating force behind America's armed forces, has created a device that can give workers unsurmountable strength and endurance, and, amazingly, it does not require an external power supply. Dubbed the FORTIS exoskeleton, this device may see use in combat, but its primary mission is to aid behind the scene by granting workers improved stamina.
FORTIS is the solution to a very real problem: the limitations of human strength. A Wired article that discusses the exoskeleton cites that most ship workers for the Navy have to carry upwards to 30 pounds of equipment while doing things like sandblasting, riveting and grinding excess metal. Naturally, these tasks are draining, especially when carrying that much weight. The article claims that even the most skilled and physical capable workers can only work for three or four minutes before they need to put their tools down and take a break. Imagine if you had to break every three or four minutes at your job just to be able to rest. How would that affect your productivity?
FORTIS is designed with exactly these parameters in mind. The exoskeleton can support up to 36 pounds by transferring the weight from the hands and arms of a worker to the ground. The Navy has already purchased two of these exoskeletons and intends to evaluate their effectiveness over the next six months to determine how useful they are in an industrial setting.
Pared down and sleek
This is not the first foray into exoskeleton technology for the U.S. armed services. Last year, DARPA revealed the tactical assault light operator suit, or TALOS, which is meant exclusively for military engagements. Unlike the FORTIS, TALOS is powered, so it can carry significantly heavier loads. It is also equipped with liquid armor capable of stopping high-caliber bullets and frag. Lightweight batteries also serve to power a built-in computer, night vision and sensors that monitor vital signs and apply wound-sealing foam. In comparison, FORTIS looks like a mini-van sitting next to a super car.
That, however, is part of the appeal. FORTIS is meant to be functional, affordable and widely available. The entire apparatus only weighs 30 pounds, so it is easily moved and donned by a single person. FORTIS is made from anodized aluminum and carbon fiber, and is worn on the outside of normal work clothes. It's joints correspond to the natural joints in a human body, such as ankles, knees and hips, and can flex from side to side at the waist. While wearing the exoskeleton, users do not suffer from reduced mobility - they can climb stairs and ladders, squat and crawl. Tools can be mounted to the front of the device, and that weight is directed through FORTIS' joints to the floor, relieving much of the stress of carrying and using cumbersome tools.
Improved functionality with no compromise
The engineers at Lockheed Martin designed FORTIS by analyzing the ways in which the human body moves as well as the stress points that are first affected by physical exhaustion. With this in mind, FORTIS is able to transfer the weight of its load, as well as its own weight, directly to the ground, not the feet of the user. This is important because feet are often one of the first parts of the body to be affected by the discomfort caused by physical exhaustion. The Wired article likens the difference to jogging in uncomfortable, ill-fitting shoes versus specialized running sneakers.
The source claims that FORTIS has already been able to increase worker productivity by as much as 27 times. For instance, the team timed how long a worker could hold a 16-pound grinder overhead without having to rest his arms. Without any mechanical assistance, the test subject was able to work continuously for approximately three minutes. While wearing the FORTIS exoskeleton, the test subject was able to work for over half an hour before requiring a short break.
Although the FORTIS was designed for use by the armed services in its shipyards, this technology will surely prove useful to other, civilian industries. For example, mining and construction are two obvious areas that would benefit from Lockheed Martin's new exoskeleton. Of course, any worker who has to work with heavy objects or operate tools over their heads, such as dock and warehouse workers, would also want a FORTIS.
Quantum computing may help to address the robotics industry's shortcomings
October 7, 2014
While the field of modern robotics has made amazing advances in the past decade, the industry is still short of reaching the standards of science fiction. Robots are capable of walking on two legs, but still have difficulties dealing with uneven surfaces and unexpected obstacles. Factory machines have taken over jobs that are dangerous for humans, but simple artificial intelligence has lead to several robot-related fatalities. Robots are still incapable of thinking for themselves, and this limitation has stunted the development of humanity's inorganic helpers. Quantum computing research at the University of Innsbruck and the Complutense University of Madrid may may be the key to reaching the next era of robotics.
Quantum in action
The challenge of helping robots to think for themselves is also the challenge of designing computers that are as powerful as the human brain. An article from ExtremeTech reports that over 80,000 processors are needed to simulate just one second of human brain activity, so achieving this goal with current technology seems impossible. Thankfully, quantum computing offers new doors to scientists, programmers and engineers.
Quantum computing make use of quantum states and quantum systems to perform calculations that are far more complex than those possible with normal computers, according to sinc. Key to the ability of quantum computers to perform faster, more complicated computations is a phenomenon called "quantum reinforcement learning." When quantum states (energy level, spin, magnetism, angular momentum) are superimposed across multiple systems, the adjacent states naturally adopt and reinforce the behaviors of their neighbors. This quantum behavior is known as "quantum logic." Quantum systems are able to facilitate numerous computations of quantum states occurring concurrently, and this property allows quantum computers to deal with an exponentially greater volume of data than today's most powerful computers.
Quantum computers are also ideal for robotics thanks to a process referred to as "quantum searching." An quantum system's entire set of states can be measured simultaneously, allowing a quantum computer to quickly isolate information that corresponds with a specific quantum state in the system. This process is referred to as "Quantum Random Walks" according to the Institute for Ethics and Emerging Technology.
Advances in quantum computing translate directly to new opportunities for the science of robotics. After all, quantum robots are quantum computer systems loaded onto physical hardware and programmed to perform certain tasks. These quantum computer systems would include searching algorithms and reinforcement learning algorithms to help robots move beyond the limitations of modern artificial intelligence.
This technology would provide robots with a capacity to learn that has never before been seen. Searching algorithms will make it easier for robots to identify and apply proper programming in every environment, while quantum reinforcement learning assists the entire system in solving complex problems. A switch to quantum computing would also greatly expand the types of complex actions that a robot could perform. Miguel A. Martin-Delgado, a researcher at the Complutense University of Madrid, noted that quantum computing breakthroughs give researchers more room to build robots that are "adapting better to environments where the classic agent does not survive." Quantum robots have the capacity to generate their own solution based on information collected from the environment, just like human beings, according to sinc.
Uniting dreamers and pragmatists
The promise of a quantum robots creates an opportunity for the robotics industry to move even further into the mainstream. Space rovers will have more tools for analyzing the delicate ecosystems found on other planets, while weather robots could be used to identify slight fluctuations in magnetic, helping humans to anticipate natural disasters. In countries that have already invested heavily in robotics solutions, like Japan, the potential for alleviating societal ills with the help of robots skyrockets immensely with quantum robotics.
The key to these advancements is the ability of quantum robots to perform tasks far more complex operations than classical robots, and IEEE Spectrum notes that this technological limitations prevent manufacturers from completely committing to robotics. Companies prefer to play it safe with machines that are unambitious in design and adept at performing a single, uncomplicated procedure. Quantum robots, an era beyond the simple mechanized arms found in today's factories, will provide more tempting investments for investors.
Ironically, the standards for evaluating a quantum robot's aesthetic quality are unlikely to differ much from how modern robots are measured. Clean lines, inviting colors and human-like features are sure to dominate quantum robot designs as much as they influence the design of current machines. Dmitry Grishin, co-founder of one of the Russia's tech giants, bluntly encapsulated these aesthetic requirements in a recent interview with IEEE Spectrum. He stresses that visually interesting designs are crucial because, "nobody will buy an ugly robot."
New detection technique used gold nanoparticles to read plasmons
October 10, 2014
A team of researchers at the University of Washington in St. Louis has discovered a new application for gold nanoparticles that could make waves in forensics, improve the effectiveness of bomb squads and help environmental scientists to detect pollutants. By coating laboratory filter paper with a gold nanoparticle substrate, researchers were able to create a "plasmonic paper," a powerful new detection tool that can characterize tiny amounts of relevant molecules. The discovery is both notable for the widespread potential applications of plasmonic paper and for advancing a commonly utilized lab technique known as surface-enhanced Raman scattering.
Enter plasmonic paper
The research team was lead by assistant professor of mechanical engineering Srikanth Singamaneni and postdoctoral scholar Limei Tian. Singamaneni and Tian produced the new detection tool by submerging cellulosic filter paper in a gold nanoparticle solution. The team hoped to create a simple visual-detection platform that could be easily used in the field to detect trace chemicals or fingerprints. The tool is particularly impressive for both enhancing the signal of detectable chemicals and for collecting protein samples that produce optical clues as they bind to the gold paper. In an article hosted by Science Daily, Tian noted that these properties make plasmonic paper uniquely advantageous for homeland defense, diagnostic science and environmental protection.
The plasmonic paper technology devised by Tian and Singamaneni is far from perfect, however. The scientists noted that the technology is not yet able to distinguish between the wide range of trace chemicals that exist in the "chemical space" encountered by police, soldiers and physicians in the field. Though the technique is effective enough to identify molecules that might predict cancer, scientists lack a strategy for making the process sufficiently selective for real-world applications. The team plans to overcome this barrier by incorporating biomimetic target-recognition elements into the gold nanoparticle substrate.
Utilizing gold in SERS
The lab technique utilized by University of Washington team in developing plasmonic paper is called surface-enhanced Raman scattering. SERS takes advantage of the Raman photon scattering that occurs when a trace chemical comes in contact with the surface of a metallic nanoparticle, according to the International Society for Optics and Phonotics. The energy carried by scattered photons corresponds with the energy of the molecule the photon was originally scattered from, and this property allows scientists to use Raman scattering as a means of distinguishing the identity of unknown molecules.
Previously, experiments with SERS utilized nanoparticle substrates made from glass, alumina or silicon. These substances are commonly used in nanoparticle science, so the academic community is quite experienced with manipulating the surfaces of these nanoparticles and utilizing their unique properties for lithography. Substrates made from glass or silicon are typically stiff and brittle, which makes them ineffective for collecting samples with a swab or from a rounded surface. This limitation has also posed a barrier for utilizing surface-enhanced Raman scattering in the field.
Tian and her team aimed to resolve these issues by creating a substrate that employed gold nanorods. In addition to having different physical properties as glass substrates, gold nanorods can be tuned to react to a specific localized surface plasmon resonance. This tuning enhances the plasmonic paper's ability to detect plasmons being emitted from a material surface.
The researchers at the University of Washington aren't the only team to take advantage of gold nanoparticles to refine surface-enhanced Raman scattering. A report from NanoTechWeb reveals that a group research project by the Institute of Laser and Information Technologies and Institute of Biochemistry and Physiology of Plants and Microorganisms in Russia have developed a similar technique using ring-shaped arrangements of gold nanoparticles. Queen Mary University in the United Kingdom is also contributing to the research.
Russian scientists approached the University of Washington's problem from a different angle. The research team aimed to use colloidal gold to enhance the strength of Raman signals by passing them through nanoscale gaps between gold particles. However, the process of ordering colloidal gold into a manageable nanoparticle array proved to be prohibitively difficult. Researchers got around this problem by instead producing high-quality silica colloidal crystals at the appropriate scale and then coating said crystals with gold nanoparticles. The result was a highly repeatable SERS response that offered greater than 10 times the enhancement of a random nanoparticle assembly. There is likely potential for cross-application between this technique and the one devised by Tian and Singamaneni. For instance, the Russian model of gold nanoparticle SERS analysis could be used to provide greater selectivity to the plasmonic paper devised at the University of Washington.
Researchers on three continents develop nanoparticle eye drops
October 10, 2014
Millions of Americans over the age of 50 suffer from severe dry eye syndrome. The conditions symptoms can be painful and debilitating, including string discharge from the eye, blurred vision and grating eyelids, according to the National Eye Institute. Dry eye can even cause permanent damage to the eye when untreated. However, modern treatments up to this point have been inconvenient for dry eye sufferers. Most require multiple applications of moisturizing eye drops every day to mitigate their symptoms. Three educational institutions worldwide have recently released studies on applications for drug-carrying nanoparticles to succeed traditional eye drops.
University of Waterloo
The University of Waterloo's nanoparticle eye drops are designed to replace over 15 doses of topical eye drop solutions. Sufferers of dry eyes will be able to be able to go an entire week between another application of the nanoparticle eye drop is necessary. The secret to the new delivery method lies in the nanoparticles added to the eye drops, laced with Cyclosporine A. This unique properties of nanoparticle allow help make this approach much more effective than using traditional eye drops.
The new technique is also significantly more efficient than traditional dry eye remedies as well. The nanoparticle solution uses only 5 percent of the amount of Cyclosporine A per dose. Shengyan Liu, PhD candidate at the University of Waterloo's Faculty of Engineering, noted that the feeling of miniscule nanoparticles resting on the eye were indistinguishable from were impossible to distinguish. Direct contact with the eyelid also allows dry eyes to absorb Cyclosporine A from the nanoparticles over five days. This extended release period is frees users from the hassle of a daily eye drop routine. Liu says that reducing the frequency that dry eye patients utilize their topical solutions will also protect them from potential over-exposure to traces amounts of toxic chemicals in found in eye drops.
The next step for the University of Waterloo's research team is to move the product into the clinical trials. Given successful trial runs, the Canadian team's nanoparticle eye drop product may be on the store shelves by 2020. However, University of Waterloo's product may not be the only nanoparticle eye drop available in the next five years.
University of Reading
A teal lead by professor Vitaliy Khutoryanskiy at the University of Reading have also recently completed research on drug carrying nanoparticles that provide long-term relief from dry eye symptoms. On average, less than 5 percent of the actual medicine found in traditional eye drops actually manages to penetrate the eye before being washed away by tears. Professor Khutoryanskiy decided to focus on maximizing the ability of nanoparticles to cling to the surface of the eye to ensure that medicine is consistently applied, according to Controlled Environments.
Another unique research approach taken by the University of Reading team is investigating is how the nanoparticle delivery method can help patients with serious eye-disorders. For instance, the team theorizes that repeated applications of drug-carrying nanoparticles may offer a less invasive form of healthcare that injecting medicine directly into a patient's eye. Khutoryanskiy points out that developing medicines that can comfortable penetrate the eye is difficult because the cornea acts as a natural defense against errant microbes or chemicals. Khuoryanskiy's team also believes that all types of drug-carrying nanoparticle applications can be improved with the addition of enhancers like cyclodextrins. Maximizing the efficiency of corneal absorption will help to make the technology as cost-effective as possible.
Patel Institute of Pharmaceutical Education and Research
Research concerning the best polymers for use in drug-laced nanoparticle solutions for dry eye was performed concurrently at the Patel Institute in Shirpur, India. The team lead by Vijay D. Wagh and Dipak U. Apar performed multiple characterization studies the pinpoint the most effective combination of nanoparticles to improve corneal absorption, notes the Journal of Nanotechnology.
One very pertinent discovery mentioned in the study is the relationship between the e concentration of the nanoparticles used to carry dry eye medication and the size of each nanoparticle. As concentration increases, so does particle size, a phenomenon that researchers believe to be a physicochemical phenomenon unique to each nanoparticle. The study concluded that of the many polymers tested, the most effective is Eudragit RL 100. The polymer is unique in that its surface charge and particle size are resistant to change, ensuring that the material remains effective even in penetrating the cornea.
All three parallel studies offered unique insights into the chemical behaviors that make nanoparticles perfect for administering medicine to the eye. Development of the next-generation polymers may improve this method even further. There will likely be a strong market for those drug-carrying nanoparticles that are also biodegradable, as these polymers ensure that this ocular delivery method will not release legions of waste chemicals into the environment.
Engineers learn from snakes to make all-terrain robot
October 9, 2014
From nanoengineering to robotics, scientists regularly draw inspiration from nature. Whether it's the tiny cellular structures that give wood its strength and flexibility or the muscle movements of birds, nature is full of useful information for performing amazing feats of engineering. Recently, engineers have been designing robots based on the movements of snakes to create all-terrain robotic assistants.
Two years ago, scientists from the Georgia Institute of Technology got to work on an all-terrain robot that could be used in search-and-rescue missions. The requirements for this robot represented several significant design challenges. For instance, the machine had to be flexible enough to traverse uneven surfaces, but it could not be so big that it couldn't get into tight spaces. Furthermore, the robot was required to have the ability to climb slopes of various pitches and compositions. Many of these feats had already been accomplished by other robots, but these machines were over-engineered and required massive amounts of energy. This meant that not only could the robots not carry their own power supplies, but they were also prone to overheating.
The team at Georgia Tech acknowledged that size and energy requirements were issues with previous models, and set out to make something more sleek, lean and efficient. Their inspiration? The snake. Hamid Marvi, a Mechanical Engineering graduate student at Georgia Tech spoke on his team's fascination with snakes.
"By using their scales to control frictional properties, snakes are able to move large distances while exerting very little energy."
The team spent several months at the Zoo Atlanta to get a first-hand look at how these creatures moved. While there, they studied and videotaped 20 different species of snakes.
Based on their observations, the scientists were able to design a machine that could move with rectilinear locomotion. In nature, snakes accomplish this method of movement by lifting their ventral scales and pulling themselves forward with a powerful, muscular traveling wave that goes from their heads to their tails.
The Georgia Tech snake robot, dubbed Scalybot 2, accomplishes rectilinear locomotion by automatically changing the angle of its scales to adjust for different terrain or slopes. With a slight change of pitch, the snakebot can generate as much or as little friction as it needs to gain traction on different surfaces. The robot is controlled with a remotely with a joystick and can move forward and backward.
However, the Georgia Tech engineers were not yet done with their snake inspired forays into robotics. Recently, the team went back to the drawing board to try to figure out how to replicate the complicated movements of sidewinder snakes in their robot.
Sidewinders and next level snake robots
Sidewinders are renowned for their unique movement patterns which allow them to quickly climb sandy slopes. However, the researchers were faced with a challenge - not only did they not understand how sidewinders moved, but neither did biologists.
In order to understand how these creatures moved, the Georgia Tech scientists teamed up with other researchers from Carnegie Mellon University and Oregon State University, and they went back to the Zoo Atlanta to study sidewinders. The Zoo Atlanta presented the perfect opportunity for studying these creatures. The sidewinders were kept in a large enclosure full of sand from the Arizona desert to which the snakes are native. It could be raised or lowered to create different angles in the sand, and air could be blown from a chamber below to create different conditions and smooth the sand after each snake was studied.
After analyzing high speed video of the movement, the team were able to determine that the snake's ability to climb sandy slopes is easier than it appears. By increasing and decreasing the amount of their body area that is in contact with the ground, the snakes are able to traverse impossibly granular surfaces.
Using what they learned, the engineers modified a snake robot, which was an updated Scalybot, so it could emulate the distinctive, elliptical sidewinder movement. Amazingly, it worked. The serpentine robot, which could previously move over even surfaces, but could not climb granular inclines, could now scale sandy ridges just like a real sidewinder. Daniel Goldman, an associate professor of physics at Georgia Tech, spoke about the team's approach to creating the new Scalybot.
"Our initial idea was to use the robot as a physical model to learn what the snakes experienced. By studying the animal and the physical model simultaneously, we learned important general principles that allows us to not only understand the animal, but also to improve the robot."
In order to accomplish this, the researchers needed to analyze both the horizontal and vertical motions that the animal performs in order to move. The press release describes this process as being similar to the way a tank moves with a revolving tread. With tanks, the tread is constantly placing itself down in front of the direction of movement while picking itself up in the rear. The snake operates similarly, but instead of moving in a cylinder, it moves in an ellipse. The sidewinder lifts some parts of its body while other parts stay on the ground. Then, as the slope increases, the cross section of the cylinder becomes flattened, creating the same effect as the tank treads.
While experimenting with the movement, the researchers realized that sidewinders use a pattern of two, independently controlled orthogonal waves to climb on sand. Studying these patterns in both the animal and the robot, the team identified three different failure regimes. By carefully adjusting the aspect ratio of the two waves, they were able to control what parts of the robots body came in contact with the sand. Based on this information, the robot was designed to be able to pass horizontal and vertical waves through its two inch by 37 inch body to climb over nearly any granulated incline.
This new snakebot should prove effective in search-and-rescue missions, but the press release also speculates that it could be used to explore alien planets. Naturally, the sand crawling robotic serpent could open new doors for automated exploration of Mars, which proved challenging for NASA's rover.
New stabilizing methods will expand applications for foam materials
October 9, 2014
Foams have a wide range of applications, from the cosmetic industry to oil production. Foams form when surface-active molecules are exposed to water. The surface-active molecules remain locked between the water and air, allowing a film of water to form a bubble. Water molecules take on a unique architecture as they react to surface-active molecules, and these special molecular behaviors are responsible for a foam's versatile applications. Foams are hard to stabilize, and this property has made it equally difficult to develop dry foams for automotive or aeronautic applications. However, a recent breakthrough by researchers at the Georgia Institute of Technology may rid foam materials of one of their biggest weaknesses.
Enter the capillary foam
Scientists have previously made attempts to stabilize foams by introducing surfactants or microscopic powders. However, the most effective additives could only be produced with materials that are not readily available, making this approach ineffective for widespread use. Sven Behrens, co-author of the study and a professor in the School of Chemical and Biomolecular Engineering, noted that the team's new approach is "much easier and more broadly applicable" than traditional foam stabilizing solutions, according to the Georgia Tech.
The new approach studied by the Georgia Tech team, capillary foams, involves adding both a generic additive and small amount of oil. The result is significantly greater foam stability. The small amount of oil naturally forms bridges between particles, stabilizing the foam and helping the surface-active molecules to resist defoaming. The research performed by Georgia Tech is especially impressive considering the phenomenon has yet to be fully understood. Additional research may even reveal more effective methods for foam stabilization.
Georgia Tech's discovery is also novel for its potential to expand the foam materials industry. The oil-additive mixture greatly expands the range of particles that can be used to stabilize foams, making it the production of stabilized foams far easier and cost effective. Likewise, the type of oil used in the mixture does not require any special properties. Even vegetable oil would be sufficient to replicate the method developed by Georgia Tech.
Oil-additive mixtures greatly improve foam stability as well. In fact, the method may even make it possible for dry foam technology to be used in parts for planes and cars. The average weight of a passenger vehicle could be greatly reduced if parts were replaced by foam materials, improving the fuel economy and cost of production.
Lessons from history
This recent breakthrough in foam technology follows several studies over the past decade. In fact, a study performed by French research groups INRA, CEA and CNRS as far back as 2011 produced a soap foam that lasted up to several months, according to Science Daily. The team hoped to use new breakthroughs in foam stability for commercial application in the cosmetic sector. Reviewing the study's complexities also shine light on the innovation and convenience of Ohio State's new model for foam stability.
Research revolved around 12-hydroxystearic fatty acid, a surface-active molecule derived from castor oil. In addition, a salt was added to make the fatty acid insoluble. The solution produced a large amount of foam when exposed to water, even when the molecules were combined in small volumes. While typical stabilizing agents at this time, the INRA foam remained stable for six months. Researchers, however, were still in the dark when it came to explaining this phenomenon.
French scientists were able to observe that utilizing 12-hydroxystearic acid at a range of temperatures had a huge impact on the formation of foam. For example, producing the foam between 20 and 60 degrees Celsius resulted in a highly rigid foam. Researchers used microscopy and neutron scattering to observe how thin films of water would pack together densely and give the foam its stability, based on temperature. For instance, the same process ran at temperatures above 60 degrees Celsius begat a foam prone to collapsing.
The experiment was also notable as an example of "green chemistry." The foam developed by the INRA and its associates made use of a naturally occurring fatty acid as its key ingredient. As a result, the process created a natural alternative to synthetic soap while also minimizing waste in production. For example, several face wash products utilize a wide range of chemicals to produce a foam. Replacing those ingredients with the 12-hydroxystearic fatty acid would reduce the cost of producing those face wash products and cut down on resource consumption.
Looking back, it's no surprise that the use of a castor oil product was key to advancing foam research in 2011. The latest findings from Georgia Tech suggest that oil bridges are integral to the formation of stable foam and that even benign vegetable oil can be used to improve foam stability.
Innovators create high-resolution, flexible displays
October 7, 2014
For the past several decades, researchers and engineers have worked to make technology smaller and more accessible. Nearly two decades ago, computers got smaller with the introduction of the first laptop computers. A few short years later, and phones were made mobile and pocket-sized. Now, materials scientists at Oxford University are trying to not only reduce the size of screens, but make them flexible. While this technology will surely be used for creating even smaller electronic devices, as well as offering new design options to the wearables industry, another group of researchers from the University of Saarland has been making efforts to create paper-thin, touch-sensitive displays that can be printed at home on a specialized printer.
The building blocks of display panels
Pixels, the tiny squares that make up nearly all digital displays, are the primary limiting factor that has always dictated the size of screens. Pixels determine things like screen resolution and dot-pitch, which determine how crisp an image can appear when displayed on a monitor or TV. Recently, scientists from Oxford University have been trying to shrink pixels as a means of ultimately making smaller display panels. The goal is to create a non-pixel, which would be a mere 100 nanometers in size. This would not only allow for smaller, high-resolution screens, but also increased flexibility. If this research proves effective, then the entire notion of the wall-mounted TV screen might end up becoming a thing of the past.
The secret to creating nano-pixel displays is in the link between the electrical and optical properties of phase change materials, which are novel compounds that can change their states from amorphous to crystalline. The researchers from Oxford discovered that by layering seven nanometers of germanium-antimony-tellurium, a phase change material, between two layers of indium tin oxide, a clear electrode, they could apply a small amount of electricity to draw images within the phase change material. At first, the team was only able to produce still images that were only visible with an atomic microscope, but the proof of concept was enough to move forward with the work.
Innovation by accident
The next step was start to move from the micro to the macro, and by using electricity to turn on or off the various nano-pixels, the team was able to create the colored dots that formed the foundation of a super high-resolution display. Harish Bhaskaran, a professor in Oxford's Department of Materials and leader of the research, spoke on his teams work.
"We didn't set out to invent a new kind of display. We were exploring the relationship between electrical and optical properties of phase change materials and then had the idea of creating GST (phase change material) 'sandwich' made up of layers just a few nanometers thick. We found that not only were we able to create images in the stack but, to our surprise, thinner layers of GST actually have us better contrast. We also discovered that altering the size of the bottom electrode layer enabled us to change the color of the image."
New potential for displays
This new model of display unit requires significantly less electricity than the commonly available LED monitors that most people are used to. The press release speculates that the flexible, paper-thin displays could allow users to turn on a power-saving 'e-reader mode,' for when they are just browsing the Internet or reading a book on their device. With the push of a button, the display could then be changed over to a different, back-lit setting that can show video.
Other design potential capitalizes on the scale and flexibility of these new displays. For instance, this material could lead to the production of significantly more versatile smart glasses since it is flexible and high-resolution. Some researchers on the project have even speculated as to the new material's potential as a means of creating smart contact lenses, which could project data directly into a person's retina.
The scientists from Oxford aren't the only ones working on creating flexible displays. At Saarbrucken University, researchers are developing flexible, customizable displays that can be designed and printed on a device not dissimilar from a home printer. Using processes called screen printing and conductive inkjet printing, the Saarbrucken team have created a method by which a person can print relatively high-resolution display with a thickness of a mere 0.1 millimeters. The appeal of this method is that people can use displays in ways never before thought possible. For instance, the wristband of a smart watch could be upgraded with new functionality so it would light up if it received a message.
Other purposes are a bit more whimsical. The press release suggests that the material could be used in postcards to add extra levels of interaction. A card depicting an antique car, for instance, could light up or become animated when you touch the image. Books could contain all kinds of hidden messages that only activate when interacted with a certain way, or stairs could light up when you step on them. At the moment, the biggest limitation placed on this technology isn't imagination, but the pricetag. The special ink required for printing these tiny display panels is expensive, and it costs over $30 to print a single DIN A4 page. However, ongoing research suggests that it may soon be possible to extend this technology beyond it's current 2D applications.
2D to 3D
The press release from Saarbrucken claims that the ink can be used on a wide range of materials, including leather, pottery, stone, metal and even wood, which means that 3D fabrications could be covered with this new printable display. In fact, new research is being conducted by the same researchers to make 3D printing materials with the same attributes and functionality in the ink. This would allow engineers to print three-dimensional objects that display information and are touch-sensitive.
Displays are everywhere as it is, but most of the are the same squares that people have been familiar with since the invention of the television. This new research from Oxford and Saarbrucken will pave the way for new forms of display panels, which could redefine the way people interact with computers and the world around them.