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News Article | November 16, 2016
Site: www.eurekalert.org

Many species of owl are able to hunt in effective silence by suppressing their noise at sound frequencies above 1.6 kilohertz (kHz) - over the range to which human hearing is most sensitive. A team of researchers studying the acoustics of owl flight - including Justin W. Jaworski, assistant professor of mechanical engineering and mechanics at Lehigh's P.C. Rossin College of Engineering and Applied Science-are working to pinpoint the mechanisms that accomplish this virtual silence to improve man-made aerodynamic design - of wind turbines, aircraft, underwater vehicles and, even, automobiles. Now, the team has succeeded - through physical experiments and theoretical modeling - in using the downy canopy of owl feathers as a model to inspire the design of a 3-D printed, wing attachment that reduces wind turbine noise by a remarkable 10 decibels - without impacting aerodynamics. They have further investigated how such a design can reduce roughness and trailing-edge noise. In particular, trailing-edge noise is prevalent in low-speed applications and sets their minimum noise level. The ability to reduce wing noise has implications beyond wind turbines, as it can be applied to other aerodynamic situations such as the noise created by air seeping through automobile door and window spaces. Their findings will be published in two forthcoming papers - one called "Bio-inspired trailing edge noise control" in the American Institute of Aeronautics and Astronautics Journal and the other called "Bio-inspired canopies for the reduction of roughness noise" in the Journal of Sound and Vibration. The researchers - from Lehigh, Virginia Tech, Florida Atlantic University and University of Cambridge - specifically looked at the velvety down that makes up the upper wing surface of many large owls - a unique physical attribute, even among birds, that contributes to owls' noiseless flight. As seen under a microscope, the down consists of hairs that form a structure similar to that of a forest. The hairs initially rise almost perpendicular to the feather surface but then bend over in the flow direction to form a canopy with interlocking barbs at the their tops - cross-fibers. Among their experiments: suspending mesh fabrics (their original design used wedding veil material!) designed to mimic the effect of the canopy over sandpaper--to create the "roughness"--and simulated air flows using the Virginia Tech Wall-Jet Wind Tunnel. After realizing that the use of a unidirectional canopy - with the cross-fibers removed - was the most effective - as it didn't produce high-frequency self-noise of the fabric canopies, but still suppressed the noise-producing surface pressure - they created a 3-D-printed, plastic attachment consisting of small "finlets" that can be attached to an airfoil (or, wing). The finlet invention may be retrofitted to an existing wing design and used in conjunction with other noise-reduction strategies to achieve even greater noise suppression. "The most effective of our designs mimics the downy fibers of an owl's wing, but with the cross-fibers removed," says Jaworski. "The canopy of the owl wing surface pushes off the noisy flow. Our design mimics that but without the cross fibers, creating a unidirectional fence - essentially going one better than the owl." The research is funded in part by the U.S. Office of Naval Research.


News Article | November 16, 2016
Site: www.sciencedaily.com

Many species of owl are able to hunt in effective silence by suppressing their noise at sound frequencies above 1.6 kilohertz (kHz) -- over the range that can be heard by humans. A team of researchers studying the acoustics of owl flight -- including Justin W. Jaworski, assistant professor of mechanical engineering and mechanics at Lehigh's P.C. Rossin College of Engineering and Applied Science-are working to pinpoint the mechanisms that accomplish this virtual silence to improve human-made aerodynamic design -- of wind turbines, aircraft, naval ships and, even, automobiles. Now, the team has succeeded -- through physical experiments and theoretical modeling -- in using the downy canopy of owl feathers as a model to inspire the design of a 3-D printed, wing attachment that reduces wind turbine noise by a remarkable 10 decibels -- without impacting aerodynamics. They have further investigated how such a design can reduce roughness and trailing-edge noise. In particular, trailing-edge noise is prevalent in low-speed applications and sets their minimum noise level. The ability to reduce wing noise has implications beyond wind turbines, as it can be applied to other aerodynamic situations such as the noise created by air seeping through automobile door and window spaces. Their findings will be published in two forthcoming papers -- one called "Bio-inspired trailing edge noise control" in the American Institute of Aeronautics and Astronautics Journal and the other called "Bio-inspired canopies for the reduction of roughness noise" in the Journal of Sound and Vibration. The researchers -- from Lehigh, Virginia Tech, Florida Atlantic University and University of Cambridge -- specifically looked at the velvety down that makes up the upper wing surface of many large owls -- a unique physical attribute, even among birds, that contributes to owls' noiseless flight. As seen under a microscope, the down consists of hairs that form a structure similar to that of a forest. The hairs initially rise almost perpendicular to the feather surface but then bend over in the flow direction to form a canopy with interlocking barbs at the their tops -- cross-fibers. Among their experiments: suspending mesh fabrics (their original design used wedding veil material!) designed to mimic the effect of the canopy over sandpaper -- to create the "roughness" -- and simulated air flows using the Virginia Tech Wall-Jet Wind Tunnel. After realizing that the use of a unidirectional canopy -- with the cross-fibers removed -- was the most effective -- as it didn't produce high-frequency self-noise of the fabric canopies, but still suppressed the noise-producing surface pressure -- they created a 3-D-printed, plastic attachment consisting of small "finlets" that can be attached to an airfoil (or, wing). The finlet invention may be retrofitted to an existing wing design and used in conjunction with other noise-reduction strategies to achieve even greater noise suppression. "The most effective of our designs mimics the downy fibers of an owl's wing, but with the cross-fibers removed," says Jaworski. "The canopy of the owl wing surface pushes off the noisy flow. Our design mimics that but without the cross fibers, creating a unidirectional fence -- essentially going one better than the owl."


News Article | February 23, 2017
Site: phys.org

It's the only realistic way that drones will have commercially viable uses such as delivering that roll of toilet paper to customers, said Manish Kumar, associate professor of mechanical engineering at the University of Cincinnati's College of Engineering and Applied Science. Kumar and his co-authors, Nicklas Stockton, a UC researcher, and Kelly Cohen, aerospace engineering professor, considered the difficulty drones have in navigating their ever-changing airspace in a study presented at the American Institute of Aeronautics and Astronautics SciTech 2017 Conference in January. This problem is compounded when the drone tries to land on a moving platform such as a delivery van or even a U.S. Navy warship pitching in high seas. "It has to land within a designated area with a small margin of error," Kumar said. "Landing a drone on a moving platform is a very difficult problem scientifically and from an engineering perspective." To address this challenge, UC researchers applied a concept called fuzzy logic, the kind of reasoning people employ subconsciously every day. While scientists are concerned with precision and accuracy in all they do, most people get through their day by making inferences and generalities, or by using fuzzy logic. Instead of seeing the world in black and white, fuzzy logic allows for nuance or degrees of truth. "In linguistic terms, we say large, medium and small rather than defining exact sets," he said. "We want to translate this kind of fuzzy reasoning used in humans to control systems." Fuzzy logic helps the drone make good navigational decisions amid a sea of statistical noise, he said. It's called "genetic-fuzzy" because the system evolves over time and continuously discards the lesser solutions. Stockton, Kumar and Cohen successfully employed fuzzy logic in a simulation to show it is an ideal system for navigating under dynamic conditions. Stockton, an engineering master's student who was lead author on the paper, is putting fuzzy logic to the test in experiments to land quadcopters on robots mounted with landing pads at UC's UAV Multi-Agent System Research (MASTER) Lab. "This landing project is a real-world problem. A delivery vehicle could have a companion drone make deliveries and land itself," Stockton said. Stockton is just the latest UC student mentored by Cohen who was offered a job, at least in part, for his experience in fuzzy logic. The U.S. Air Force offered Stockton a federal position to continue his engineering research at Wright-Patterson Air Force Base when he graduates this summer. UC doctoral graduate Nick Ernest, another student of Cohen's, started an artificial intelligence company called Psibernetix, Inc., that demonstrated the power of fuzzy logic last year when a fuzzy-logic-based artificial intelligence, dubbed ALPHA, bested a human fighter pilot in simulated dogfights. Retired U.S. Air Force Col. Gene Lee called ALPHA, "the most aggressive, responsive, dynamic and credible AI I've seen to date." Professor Cohen is confident about the team's approach. "Compared to other state-of-the-art techniques of adaptive thinking and deep learning, our approach appears to possess several advantages. Genetic fuzzy is scalable, adaptable and very robust," Cohen said. Cohen has authored more than 100 papers on fuzzy logic, a subject that is attracting increasing attention because of its broad applications in everything from manufacturing to medicine. UC is a world leader in fuzzy logic and teaches it at the undergraduate level, Cohen said. "It's important to introduce our students at an early stage to fuzzy approaches as it also provides them with an advantage as they enter the job market," Cohen said. Explore further: Using 'fuzzy logic' to optimize hybrid solar-battery systems


MIAMI, Dec. 01, 2016 (GLOBE NEWSWIRE) -- NASA virtual reality pioneer Evelyn Miralles, one of the world’s leading authorities in virtual reality, will keynote the 1st annual Hispanicize CMO Summit of Hispanicize 2017 Week (www.HispanicizeEvent.com), the 8th annual Latino trends and newsmakers event that will take place in Miami, April 3-6, 2017. Presented by Hispanicize 2017, in partnership with PRWeek, the Hispanicize CMO Summit will take place on April 3. (Register at http://bit.ly/Hispz17Register). “Evelyn will bring powerful insights and creative ideas about how virtual reality is starting to radically transform our world and the ways that brands and customers alike can leverage what is coming,” said Manny Ruiz, Founder and CEO of the Hispanicize Media Group that owns the Hispanicize event. “Naming Evelyn as our first keynoter underscores how incredibly special the sessions and speakers for this exclusive summit will be.” For more than 20 years, Miralles has worked at NASA Johnson Space Center for the Virtual Reality Laboratory to enhance Human Spaceflight. Her work as Virtual Reality Principal Engineer and Technology Strategist has been integral to train astronauts to perform one of the most dangerous excursions of their lives, working outside a spacecraft in microgravity. Miralles has supported most of the Space Shuttle and all of the International Space Station missions since 1992. She co-wrote the Dynamic Onboard Ubiquitous Graphics software (DOUG) which has been called ‘fundamental’ for flight planning and was honored with multiple Outstanding Flight Software awards. She is also the recipient of numerous NASA’s recognitions, including the NASA Flight Safety Award, and professional, such as the ‘CNET in Spanish Top 20 most influential Hispanics in the US’ for 2 years in a row, 2015 and 2016. She is also the recipient of the ‘Distinguish Alumna Award’ by the University of Houston Clear Lake in 2016. Miralles continues to lend her experience and knowledge to the field of Computing, Virtual and Mix Realities on a national level, within government agencies and universities. She has also served as chair of the Extra-Vehicular Activity Technical Committee for the Houston section of the American Institute of Aeronautics and Astronautics (AIAA). Among her proudest roles, however, is to encourage students and young women to pursue careers in science, technology, engineering and math (STEM) through fairs, lectures and other outreach efforts. Access to the Hispanicize CMO Summit will be limited exclusively to brands, agencies and media companies on a first come, first served basis. To purchase the special, $425 Hispanicize CMO Summit only badge, or to purchase the $900 badge that includes full access to the Hispanicize CMO Summit and all Hispanicize 2017, visit http://bit.ly/Hispz17Register. About The Hispanicize Event  Now in its 8th year, Hispanicize 2017 Week (www.HispanicizeEvent.com) (#Hispz17) is the iconic, largest annual event for Latino trendsetters and newsmakers in digital content creation, journalism, marketing, entertainment and tech entrepreneurship. Hispanicize 2017 is expected to gather more than 3,000 of the nation’s most influential Latino professionals from the industries of digital content creation, journalism, music, marketing, film and business over four days. The event will take place in downtown Miami’s JW Marriott Marquis Hotel, April 3-6, 2017. The Hispanicize event is a launch pad for creative endeavors, new products, technologies, marketing campaigns, films, books, music and more targeting Latinos in the U.S. and/or Puerto Rico. The Hispanicize event is owned and operated by Hispanicize Media Group, LLC, the parent company of DiMe Media, Hispanic Kitchen and the Hispanic PR Blog. The Hispanicize Event can be found on Facebook https://www.facebook.com/Hispanicize, Instagram (@HispanicizeEvent) and Twitter (@Hispanicize).


News Article | February 23, 2017
Site: www.eurekalert.org

Using fuzzy logic, researchers at the University of Cincinnati program drones to make better navigational decisions on the fly The buzzword in drone research is autonomous -- having the unmanned aerial vehicle do most or all of its own flying. It's the only realistic way that drones will have commercially viable uses such as delivering that roll of toilet paper to customers, said Manish Kumar, associate professor of mechanical engineering at the University of Cincinnati's College of Engineering and Applied Science. Kumar and his co-authors, Nicklas Stockton, a UC researcher, and Kelly Cohen, aerospace engineering professor, considered the difficulty drones have in navigating their ever-changing airspace in a study presented at the American Institute of Aeronautics and Astronautics SciTech 2017 Conference in January. This problem is compounded when the drone tries to land on a moving platform such as a delivery van or even a U.S. Navy warship pitching in high seas. "It has to land within a designated area with a small margin of error," Kumar said. "Landing a drone on a moving platform is a very difficult problem scientifically and from an engineering perspective." To address this challenge, UC researchers applied a concept called fuzzy logic, the kind of reasoning people employ subconsciously every day. While scientists are concerned with precision and accuracy in all they do, most people get through their day by making inferences and generalities, or by using fuzzy logic. Instead of seeing the world in black and white, fuzzy logic allows for nuance or degrees of truth. "In linguistic terms, we say large, medium and small rather than defining exact sets," he said. "We want to translate this kind of fuzzy reasoning used in humans to control systems." Fuzzy logic helps the drone make good navigational decisions amid a sea of statistical noise, he said. It's called "genetic-fuzzy" because the system evolves over time and continuously discards the lesser solutions. Stockton, Kumar and Cohen successfully employed fuzzy logic in a simulation to show it is an ideal system for navigating under dynamic conditions. Stockton, an engineering master's student who was lead author on the paper, is putting fuzzy logic to the test in experiments to land quadcopters on robots mounted with landing pads at UC's UAV Multi-Agent System Research (MASTER) Lab. "This landing project is a real-world problem. A delivery vehicle could have a companion drone make deliveries and land itself," Stockton said. Stockton is just the latest UC student mentored by Cohen who was offered a job, at least in part, for his experience in fuzzy logic. The U.S. Air Force offered Stockton a federal position to continue his engineering research at Wright-Patterson Air Force Base when he graduates this summer. UC doctoral graduate Nick Ernest, another student of Cohen's, started an artificial intelligence company called Psibernetix, Inc., that demonstrated the power of fuzzy logic last year when a fuzzy-logic-based artificial intelligence, dubbed ALPHA, bested a human fighter pilot in simulated dogfights. Retired U.S. Air Force Col. Gene Lee called ALPHA, "the most aggressive, responsive, dynamic and credible AI I've seen to date." Professor Cohen is confident about the team's approach. "Compared to other state-of-the-art techniques of adaptive thinking and deep learning, our approach appears to possess several advantages. Genetic fuzzy is scalable, adaptable and very robust," Cohen said. Cohen has authored more than 100 papers on fuzzy logic, a subject that is attracting increasing attention because of its broad applications in everything from manufacturing to medicine. UC is a world leader in fuzzy logic and teaches it at the undergraduate level, Cohen said. "It's important to introduce our students at an early stage to fuzzy approaches as it also provides them with an advantage as they enter the job market," Cohen said. The research was funded by a $500,000 grant from the National Science Foundation.


News Article | February 27, 2017
Site: phys.org

What could these events have in common? Each extremely complex task is accomplished by individuals following very simple rules. But to make the drones do it, a bit of nature's magic must be captured in a mathematical formula. "Nature may not proactively use mathematics, nor does it have foresight. It behaves in ways driven by feedback, implicit drive for adaptation, and a certain degree of apparent randomness," said Souma Chowdhury, PhD, assistant professor of mechanical and aerospace engineering in the University at Buffalo's School of Engineering and Applied Sciences. "But we can look at what kind of mathematical principles define that behavior. Once we have that, we can use it to solve very complex problems." Chowdhury is pioneering a way to program a team of drones to quickly map an oil spill. His computational efforts, in a paper which he co-authored with UB students Zachary Ball and Philip Odonkor, were presented in January at the American Institute of Aeronautics and Astronautics' Science and Technology Forum. The study, called "A Swarm-Intelligence Approach to Oil Spill Mapping using Unmanned Aerial Vehicles," optimized and simulated a five-drone swarm that can map a nearly one-kilometer wide spill in nine minutes. To make that work, Chowdhury had to overcome the lack of communication bandwidth typical of a flying ad hoc network and the short battery life of off-the-shelf drones. Following the principles partly inspired by the dynamics of a flock of birds, Chowdhury devised a method for the drones to quickly record whether they are over water, oil or the edge of the spill. In addition, the drones assume that the space around the oil they have spotted is also oil, although that is recorded as less than certain. This simple information is shared with the other drones in the swarm, as opposed to sharing actual images or video, which would require too much bandwidth. "Communication is the foundation of any swarm," he said. As the drones move from point to point over the spill, they avoid going over space that other drones have already covered. Thus, with five drones making observations every five seconds, the size of the spill can be determined quickly.The drones also fly to their base, on a boat, when their batteries get low. The drones that replace them on the search already have the information from all the other drones, so they avoid previously mapped locations."The thematic focus of my lab is developing computational design approaches that take inspiration from nature," Chowdhury said. The low computer power—each drone can operate with a $35 Raspberry Pi computer—keeps costs low. Chowdhury's approach accomplishes a complex task using simple agents. "There is no need for human interaction during its entire mission," he said. "That's the big deal." Another big deal is the cost. Chowdhury's approach assumes simple, affordable drones, which makes it accessible to many more people. "This task can be accomplished by off-the-shelf drones that cost under $1,000. All they need is to have a simple drone-mountable camera system and use our software," he said. Collision avoidance is another challenge for the swarm, and here too, Chowdhury is following nature's simple rules. In recent work reported by the University of Queensland, researchers watched very carefully how parrots never crashed into each other. They observed through tunnel experiments that they always veer to the right, a simple rule that keeps every member of the flock safe. Chowdhury's lab is exploring how using similar principles, drones can pre-emptively turn a certain angle to the right when they sense another flying member of the swarm. He is writing that in a companion paper to be submitted to another international conference later this year. Swarming drones could be used elsewhere, such as mapping forest fires or other natural disasters. It's possible they could be used to help locate people trapped after an earthquake by changing the type of cameras used.


News Article | February 27, 2017
Site: www.eurekalert.org

BUFFALO, N.Y. -- Thousands of ants converge to follow the most direct path from their colony to their food and back. A swarm of inexpensive, unmanned drones quickly map an offshore oil spill. What could these events have in common? Each extremely complex task is accomplished by individuals following very simple rules. But to make the drones do it, a bit of nature's magic must be captured in a mathematical formula. "Nature may not proactively use mathematics, nor does it have foresight. It behaves in ways driven by feedback, implicit drive for adaptation, and a certain degree of apparent randomness," said Souma Chowdhury, PhD, assistant professor of mechanical and aerospace engineering in the University at Buffalo's School of Engineering and Applied Sciences. "But we can look at what kind of mathematical principles define that behavior. Once we have that, we can use it to solve very complex problems." Chowdhury is pioneering a way to program a team of drones to quickly map an oil spill. His computational efforts, in a paper which he co-authored with UB students Zachary Ball and Philip Odonkor, were presented in January at the American Institute of Aeronautics and Astronautics' Science and Technology Forum. The study, called "A Swarm-Intelligence Approach to Oil Spill Mapping using Unmanned Aerial Vehicles," optimized and simulated a five-drone swarm that can map a nearly one-kilometer wide spill in nine minutes. To make that work, Chowdhury had to overcome the lack of communication bandwidth typical of a flying ad hoc network and the short battery life of off-the-shelf drones. Following the principles partly inspired by the dynamics of a flock of birds, Chowdhury devised a method for the drones to quickly record whether they are over water, oil or the edge of the spill. In addition, the drones assume that the space around the oil they have spotted is also oil, although that is recorded as less than certain. This simple information is shared with the other drones in the swarm, as opposed to sharing actual images or video, which would require too much bandwidth. "Communication is the foundation of any swarm," he said. As the drones move from point to point over the spill, they avoid going over space that other drones have already covered. Thus, with five drones making observations every five seconds, the size of the spill can be determined quickly. The drones also fly to their base, on a boat, when their batteries get low. The drones that replace them on the search already have the information from all the other drones, so they avoid previously mapped locations. "The thematic focus of my lab is developing computational design approaches that take inspiration from nature," Chowdhury said. The low computer power -- each drone can operate with a $35 Raspberry Pi computer -- keeps costs low. Chowdhury's approach accomplishes a complex task using simple agents. "There is no need for human interaction during its entire mission," he said. "That's the big deal." Another big deal is the cost. Chowdhury's approach assumes simple, affordable drones, which makes it accessible to many more people. "This task can be accomplished by off-the-shelf drones that cost under $1,000. All they need is to have a simple drone-mountable camera system and use our software," he said. Collision avoidance is another challenge for the swarm, and here too, Chowdhury is following nature's simple rules. In recent work reported by the University of Queensland, researchers watched very carefully how parrots never crashed into each other. They observed through tunnel experiments that they always veer to the right, a simple rule that keeps every member of the flock safe. Chowdhury's lab is exploring how using similar principles, drones can pre-emptively turn a certain angle to the right when they sense another flying member of the swarm. He is writing that in a companion paper to be submitted to another international conference later this year. Swarming drones could be used elsewhere, such as mapping forest fires or other natural disasters. It's possible they could be used to help locate people trapped after an earthquake by changing the type of cameras used.


News Article | January 5, 2016
Site: www.scientificcomputing.com

The nation’s airlines could realize more than $250 billion dollars in savings in the near future thanks to green-related technologies developed and refined by NASA’s aeronautics researchers during the past six years. These new technologies, developed under the purview of NASA’s Environmentally Responsible Aviation (ERA) project, could cut airline fuel use in half, pollution by 75 percent and noise to nearly one-eighth of today’s levels. “If these technologies start finding their way into the airline fleet, our computer models show the economic impact could amount to $255 billion in operational savings between 2025 and 2050,” said Jaiwon Shin, NASA’s associate administrator for aeronautics research. Created in 2009 and completed in 2015, ERA’s mission was to explore and document the feasibility, benefits and technical risk of inventive vehicle concepts and enabling technologies that would reduce aviation’s impact on the environment. Project researchers focused on eight major integrated technology demonstrations falling into three categories — airframe technology, propulsion technology and vehicle systems integration. By the time ERA officially concluded its six-year run, NASA had invested more than $400 million, with another $250 million in-kind resources invested by industry partners who were involved in ERA from the start. “It was challenging, because we had a fixed window, a fixed budget and all eight demonstrations needed to finish at the same time,” said Fayette Collier, ERA project manager. “We then had to synthesize all the results and complete our analysis so we could tell the world what the impact would be. We really did quite well.” Here is a brief summary of each of the eight integrated technology demonstrations completed by the ERA researchers: As part of the closeout work for the ERA project, information and results regarding each of these technology demonstrations were categorized and stored for future access and use by the aerospace industry, and will be discussed at the American Institute of Aeronautics and Astronautics Sci-Tech Conference in San Diego this week. For more information about NASA aeronautics research, go to: http://www.nasa.gov/aeronautics


News Article | February 28, 2017
Site: www.futurity.org

Engineers are testing a new method to program a team of drones to quickly map an oil spill. The work is inspired by nature and guided by a mathematical formula. “Nature may not proactively use mathematics, nor does it have foresight. It behaves in ways driven by feedback, implicit drive for adaptation, and a certain degree of apparent randomness,” says Souma Chowdhury, assistant professor of mechanical and aerospace engineering in the University at Buffalo’s School of Engineering and Applied Sciences. “But we can look at what kind of mathematical principles define that behavior. Once we have that, we can use it to solve very complex problems.” In a recent paper, Chowdhury’s team describe how they optimized and simulated a five-drone swarm that can map a nearly one-kilometer wide spill in nine minutes. They presented the results at the American Institute of Aeronautics and Astronautics’ Science and Technology Forum. The team had to overcome the lack of communication bandwidth typical of a flying ad hoc network and the short battery life of off-the-shelf drones. Following the principles partly inspired by the dynamics of a flock of birds, Chowdhury devised a method for the drones to quickly record whether they are over water, oil, or the edge of the spill. In addition, the drones assume that the space around the oil they have spotted is also oil, although that is recorded as less than certain. This simple information is shared with the other drones in the swarm, as opposed to sharing actual images or video, which would require too much bandwidth. “Communication is the foundation of any swarm,” he says. As the drones move from point to point over the spill, they avoid going over space that other drones have already covered. Thus, with five drones making observations every five seconds, the size of the spill can be determined quickly. The drones also fly to their base, on a boat, when their batteries get low. The drones that replace them on the search already have the information from all the other drones, so they avoid previously mapped locations. “The thematic focus of my lab is developing computational design approaches that take inspiration from nature,” Chowdhury says. The low computer power—each drone can operate with a $35 Raspberry Pi computer—keeps costs low. Chowdhury’s approach accomplishes a complex task using simple agents. “There is no need for human interaction during its entire mission,” he says. “That’s the big deal.” Another big deal is the cost. Chowdhury’s approach assumes simple, affordable drones, which makes it accessible to many more people. “This task can be accomplished by off-the-shelf drones that cost under $1,000. All they need is to have a simple drone-mountable camera system and use our software,” he says. Collision avoidance is another challenge for the swarm, and here too, Chowdhury is following nature’s simple rules. In recent work reported by the University of Queensland, researchers watched very carefully how parrots never crashed into each other. They observed through tunnel experiments that they always veer to the right, a simple rule that keeps every member of the flock safe. Chowdhury’s lab is exploring how using similar principles, drones can pre-emptively turn a certain angle to the right when they sense another flying member of the swarm. He is writing that in a companion paper to be submitted to another international conference later this year. Swarming drones could be used elsewhere, such as mapping forest fires or other natural disasters. It’s possible they could be used to help locate people trapped after an earthquake by changing the type of cameras used.


News Article | January 24, 2017
Site: www.techtimes.com

The transformations which are responsible for the decreased temperatures inside tornadoes have been scientifically analyzed. For the first time, a research paper makes an analytical description of the phenomenon. The study, published online, Jan. 11, in the Journal of Aircraft of the American Institute of Aeronautics and Astronautics, represents the analysis on a very violent tornado which took place in 1955, in Scottsbluff, Nebraska. During the tornado, three members of a local radio station were live from the scene and took shelter in the basement of a stone building. Inside, they noticed bizarre climatic changes, among which the temperature dropping from a mid-summer average, progressively, until the reporters were feeling plain cold. They also reported that it's increasingly difficult to breathe as the tornado passed through the area where they were hiding. Since that storm, 61 years have passed. The exact cause of the phenomena accompanying the tornado, however, remained unexplained until this new research, where a mathematical model of a turbulent compressible vortex was formulated. In an attempt to solve this mystery, Georgios Vatistas, the scientist who led the research, expanded his previous theoretical research on vortices. The new analysis includes the effects described by the radio broadcasters, i.e. density variation and turbulence "Using this new advanced approach, we were able to identify the cause of the temperature drop inside vortices for the first time ever," noted Vatistas. The research team spotted the cause responsible for the temperature drop inside vortices, which is a first-time formal discovery. "[...] the present investigation identifies the cause of the Ranque-Hilsch-like thermal effect observed in unconfined compressible vortices. In comparison to laminar vortices, the center of a turbulent gaseous vortex is found to be cooler, thinner, and under lower-pressure conditions," noted the research paper. The research team discovered that the temperature dropped from 27°C (80.6°F) to 12°C (53.6°F). According to the paper, the air density was 20 percent lower compared to high altitudes. The researchers observed that, far from the axis of the rotation, the gas heated up at first, reaching a static temperature maximum and then went down to a subambient minimum at the vortex center. This theory is in complete opposition compared to previous scientific papers, as part of which the converging flow cooled down monotonically with decreasing radius. The importance of this research, however, does not just address the phenomenon of tornadoes, as the data could also be employed in other connected fields where temperature mechanics are important, ranging from electronic compounds to heal seals. Tornadoes are a recurring phenomenon in the United States, where the average number of tornadoes per year is 1,224. According to data by U.S. Tornadoes, some states are in more danger than others, as data from 1991 to 2015 suggests. "The top 10 states for tornadoes as of the most recent average are as follows, in order from high to low: Texas, Kansas, Oklahoma, Florida, Nebraska, Illinois, Colorado, Iowa, Alabama, Missouri, and Mississippi," noted the website. © 2017 Tech Times, All rights reserved. Do not reproduce without permission.

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