Articles tagged with Sonar
A new study by Tel Aviv University researchers found that fruit bats integrate vision and echolocation to see and use their eyes as much as they hear and use echolocation. The team trained the bats to land on objects in complete darkness, where they transformed echoes into visual images.
Bats use echolocation by emitting ultrasonic signals and analyzing echoes to detect objects, but their navigational system relies on a surprisingly small amount of spatial information. This allows them to navigate effectively despite receiving an 'extremely fuzzy picture' of their environment.
A CT scan of a 30-million-year-old fossil indicates that echolocation evolved independently in dolphins and other toothed whales. The discovery suggests that the evolution of echolocation may have occurred multiple times within this lineage.
Researchers found that echolocation was a major driver of skull shape evolution in bats from 58-34 million years ago. Diet played a more dominant role in shaping skulls starting around 26 million years ago, but not uniformly across all bat species. The study provides new insights into the evolutionary forces behind bat diversity.
Researchers at Hokkaido University used sonar to map the underwater shape of Grey Glacier, revealing a submerged terrace extending 100 meters beyond its visible portion. This unique structure is different from ocean-bound glaciers and can lead to huge chunks of ice falling off, posing a safety risk to humans in the vicinity.
A recent study reveals that sonar disturbs the feeding behavior of blue whales, especially in deep patches of krill. The researchers tracked the whales' movements using suction tags and found that they stop feeding when sonar signals are present, but often resume soon after.
Researchers found that beaked whales prefer areas with dense patches of deep-sea squid, which are essential for their survival. In contrast, nearby sonar-free areas lack these prey hotspots, making it difficult for the whales to obtain enough food to survive.
University of Michigan researchers have developed a technique to reveal hidden information in sound waves by shifting frequencies, allowing for improved detection and tracking capabilities in sonar systems. This breakthrough could enhance performance in naval vessels and medical imaging devices, such as biomedical ultrasound.
Whales and dolphins use a narrow beam of high intensity sound to find food in dark or murky waters; size affects the ability to focus this sense.
Researchers at the University of Bristol discovered that moth wing scales can absorb echolocation sound frequencies used by bats. The finding could lead to development of thin and lightweight resonant sound absorbers.
Some moth species use sound-absorbing scales to evade bats' echolocation. The scales vibrate at resonant frequencies that overlap with bats' biosonar range, creating acoustic camouflage.
Scientists study bat and dolphin sonar systems to improve man-made active sensing technologies. Bat species use frequency-modulating calls to overcome acoustic interference, whereas dolphins rely on short clicks with minimal overlap.
A new study reveals that bats' loss of UV vision may be linked to the development of advanced echolocation abilities. The research found that most bat species with high-duty cycle echolocation have non-functional SWS1 genes, suggesting a trade-off between vision and hearing.
A fully autonomous robot, Robat, utilizes a bat-like approach by emitting sound and analyzing echoes to create a detailed map of its surroundings. It successfully navigates through a new outdoor environment and classifies objects using an artificial neural network.
The 'Robat' uses echolocation to navigate novel environments by emitting sound and analyzing the returning echoes to generate a map of space. It is equipped with an ultrasonic speaker and two microphones that classify borders and shapes of objects encountered, avoiding obstacles.
Researchers at MIT Media Lab have developed a system called TARF that uses underwater sonar signals to transmit data to airborne receivers, breaking through the water-air barrier. The system consists of an underwater acoustic transmitter and a highly sensitive receiver that decodes the vibrations caused by the sonar signal.
Humpback whale songs may be used for echolocation, allowing singers to analyze their surroundings and locate other whales. This challenges the long-held assumption that whale songs are primarily used for reproductive purposes, instead suggesting a more complex cognitive process at play.
Researchers have developed an algorithm inspired by dolphin echolocation, which can disentangle overlapping signals and provide more precise information on object shape. This breakthrough technology could improve medical ultrasound imaging and measure organ membrane thickness, among other applications.
Hoary bats exhibit unusual silent behavior during their fall mating season, potentially to avoid eavesdropping from competitors and mates. The study suggests that this 'inconspicuous echolocation' may provide an advantage in the mating game but poses a deadly risk when encountering obstacles like wind turbines.
Researchers found that Egyptian fruit bats use a technique similar to frequency-scanning sonar, pointing different frequencies of sound at slightly different angles to create fine-grained acoustic images. This discovery could lead to the development of cheap sensors with sensing capability.
Researchers found that simulated anthropogenic noise exposure physiologically impacted blue crabs and lobsters, causing increased stress responses. The study also revealed behavioral impacts, including aggressive behaviors and reduced feeding, highlighting the need for environmental permitting in coastal areas.
Neural recordings of wild bats reveal a layered structure in the superior colliculus facilitating rapid tracking and capturing of prey through echolocation. The study contributes to understanding of SC function during naturalistic behaviors, finding both sensory and motor neurons throughout the midbrain region.
Researchers at Lund University found that large ears increase air resistance in bats, making flight less energy-efficient. However, they also provide better hearing and generate more lift, which is crucial for echolocation. The study suggests that evolution has made a compromise between flying efficiency and optimal echolocation ability.
Researchers found that bats produce fewer calls, spend less time near vertical glass surfaces, and approach at a more acute angle, highlighting the 'blind spot' in their echolocation ability. The study's findings underscore the negative impact of human development on wildlife, particularly injured or dead bats often found near buildings.
A new study provides in-depth analysis of human mouth clicks used in echolocation, revealing brief and focused clicks with distinct acoustic patterns. The findings enable the creation of virtual human echolocators, allowing researchers to investigate object features without impractical measurements.
Researchers at UC Riverside found pallid bats resistant to Arizona bark scorpion venom, with amino acid substitutions in voltage gated sodium ion channels. The study may have implications for understanding and managing human pain.
A new sonar-based method estimates Antillean Manatees in the San San Pond Sak wetland, finding a lower population than previously thought. The study suggests modifications to protect manatees from illegal fishing nets and human activities.
The oilbird's unique combination of sharp vision, smell, tactile sensation, and echolocation abilities inspire researchers to create more advanced drones. By studying the bird's sensory system, scientists hope to develop models that can be used in robotics engineering.
Researchers used a deep-diving robot to study deep scattering layers, finding that they contain discrete groups or 'schools' of squids, fishes, and crustaceans. These groups have distinct boundaries and are formed by similar-sized animals, with smaller animals staying closer together.
Researchers have identified that visually impaired people use the timbre, in addition to pitch and loudness, of echoes to navigate their surroundings. This skill is similar to animal echolocation but differs in how humans use sound to locate objects.
Researchers have created a new seafloor map that provides detailed information about the 2015 eruption at Axial Seamount. The map reveals 14 separate lava flows containing nearly 156 million cubic meters of lava, as well as precise locations of eruptive fissures.
Mexican free-tailed bats have specialized facial muscles that aid their ability to manipulate the acoustic projection pattern of their sonar pulse emissions. The unique muscles enable the bats to adjust the shape of their mouth cavity, creating a wide-angle beam or a narrow beam with varying degrees of aperture.
Researchers recorded narwhal clicks in Baffin Bay, finding they have the most directional sonar signal of any species. Narwhals scan vertically with sound during ascents and descents.
A recent study on two echolocating bat species found a contraction of smell receptors and loss of vision-related genes, indicating evolutionary trade-offs. The research also revealed genetic adaptations associated with high altitudes in the great leaf-nosed bats.
A newly-named fossil whale species, Echovenator sandersi, had superior high-frequency hearing ability, helping scientists understand the evolution of this specialized sense. The study, published in Current Biology, pushes the origin of high frequency hearing in whales farther back in time.
Researchers found that bats recognize locations by remembering unique echo signatures, allowing them to form cognitive maps of their environment. The study suggests that prominent landmarks play a key role in template-based place recognition.
Marine biologists have discovered that shark traffic in and out of Palmyra Atoll's lagoon peaks between 7-8 pm. The study used dual-frequency identification sonar to monitor shark movement, revealing a rush hour for these marine predators.
Researchers have developed a software called ForcePhone that allows smartphones to detect force or pressure on their screens or bodies, enabling users to command devices with gestures. The technology uses the phone's microphone and speaker to translate vibrations into commands, offering a natural interface beyond basic touch interfaces.
Researchers develop model that suggests mucus plays crucial role in dolphin sonar click production. The model accurately reproduces two distinct parts of a dolphin click: an initial loud thump and extended ring.
Whitlow Au, a renowned expert in dolphin biosonar, receives the prestigious Gold Medal from the Acoustical Society of America. His research has focused on understanding why dolphin biosonar is superior to man-made sonar.
Scientists have discovered five new limestone sea stacks, or 'Drowned Apostles', 50m beneath the water's surface 6km off Victoria's southern coast. The unexpected find challenges normal erosion rates and provides insights into the region's reef ecosystems.
A study measuring underwater noise from ships found that low-frequency noise affects killer whales, while medium-high frequencies also interfere with their communication and echolocation. Reducing ship speed can help mitigate this noise pollution.
John L. Butler, Chief Scientist at Image Acoustics, Inc., received the Acoustical Society of America's Silver Medal in Engineering Acoustics for advancing acoustic transducer and transducer array design. The award recognizes contributions to the advancement of science through acoustic principles.
In a study published in PLOS ONE, researchers found that barbastelle bats emit two different types of weak echolocation signals alternately through their nose and mouth. These 'stealth echolocation' signals facilitate prey detection while minimizing environmental disturbance.
Researchers have mapped dolphin brain circuitry for the first time, revealing multiple areas associated with auditory information. The study used diffusion tensor imaging on preserved dolphin brains and found neural pathways similar to those of bats.
Henry Cox, Senior Fellow at Lockheed Martin, has made fundamental and practical contributions to array signal processing, underwater acoustics, and sonar systems engineering. The Helmholtz-Rayleigh Silver Medal is awarded for interdisciplinary contributions named after two great pioneers of acoustics.
Research by Dr. Mel Goodale shows that blind echolocation experts recruit regions of the brain associated with visual perception when making echo-based assessments of objects. They can also perceive material properties such as hardness and density through auditory cues, an effective form of sensory substitution for vision.
Engineers at Virginia Tech have created a novel dynamic sonar system inspired by horseshoe bats that can navigate complex environments with ease. The system uses two receiving channels and one emitting channel to replicate the key motions in the bat's ears and nose, reducing power consumption and computing resources.
Researchers have developed a prototype of a dynamic sonar system inspired by horseshoe bats, which could lead to more effective man-made sonar systems. The system uses principles similar to those used by bats to navigate and hunt in the dark.
Researchers at Ohio State University have developed a new automated treadmill that uses sonar to change speeds automatically, mimicking the experience of running outdoors. The device provides an accurate measure of aerobic capacity and has been shown to improve VO2 max scores by 4-7% compared to standard treadmills.
Researchers discover that luna moths use tail-spinning to fool bat sonar, increasing survival rate by 47%. The findings expand knowledge of anti-predator strategies and have implications for military sonar development.
Researchers discovered that hunting bats rely on echolocation calls from fellow bats to pinpoint insect patches. By aggregating and sharing this information, bats can improve their chances of finding prey despite the challenges posed by sparse distribution and long flight distances.
Researchers discover that echolocation can induce a 'size-weight illusion' in blind individuals, similar to sighted people's experience. This finding suggests that echolocation may have the potential to be a complete sensory replacement for vision.
NOAA and partners have released detailed sonar maps and images of the historic SS City of Rio de Janeiro, a San Francisco shipwreck that sank in 1901, killing 128 people. The wreck was located using cutting-edge technology in the Gulf of the Farallones National Marine Sanctuary.
Researchers found that Old World fruit bats produce bio-sonar clicks with their wings, enabling them to find their way in the dark. The ability is poorer than that of other echolocating species, but provides insight into how echolocation evolved over time.
Mexican free-tailed bats employ a unique strategy by jamming the sonar of competitors to capture prey in complete darkness. The researchers observed that bats almost always missed their prey when another bat was jamming them, and this behavior increased with precise timing and frequency.
New research suggests that bats' brains use the temporal binding hypothesis to focus on targets in cluttered scenes, which could inspire new navigation technology. By studying bat echolocation, scientists have developed a better understanding of how to design radar and sonar systems for real-time performance.
Researchers found that prestin, a key hearing gene, has evolved independently to play a critical role in echolocation of bats and dolphins. The protein enables these animals to navigate through murky waters or find food in the dark using high-frequency sound waves.
Researchers at MIT describe a new technique that could reduce the number of sensors needed for terahertz or millimeter-wave imaging by a factor of 10, enabling more practical high-resolution imaging systems. The technique exploits the sparsity of scenes in certain ranges, allowing for efficient reconstruction without aliasing.
A study by the Department of Energy's Pacific Northwest National Laboratory found that commercially available sonar systems produce signals within the hearing range of killer whales and other marine mammals. The sounds are quiet but audible to animals beyond a few hundred meters, potentially affecting their behavior.