Using the same basic physics based on the familiar hollow tone produced by blowing across an empty bottle, researchers in Switzerland have developed a sound-powered propulsion system that can steer microrobots and even lift tiny machines.
In a new study published in Science Advances, engineers at the Swiss Federal Institute of Technology Lausanne (EPFL) demonstrated that 3D-printed cavities known as Helmholtz resonators can convert sound into directed jets of air and usable thrust.
The researchers built devices ranging from centimeters down to micrometers, used sound to propel and steer tiny boats, and created two microscopic flying machines—one microrobot lifted directly by acoustic thrust and another using rapidly spinning rotor blades. One version generated nearly five times its own weight in thrust, while another spun at up to 13,000 revolutions per minute to produce aerodynamic thrust.
The work points to a new way to power small robots without conventional motors, while also exposing the considerable engineering problems that remain before such machines can operate autonomously.
“While acoustic resonators have been extensively studied in liquids for the realization of untethered microrobots, their implementation in air remains largely unexplored,” researchers write. “The actuation scheme is compatible with even further miniaturization, pushing the boundaries of robotics and aeronautics.”
The idea behind the technology is surprisingly familiar. Blow across the top of an empty bottle and you hear a deep, hollow note created as the air trapped inside begins to vibrate.
Known as Helmholtz resonance, the effect happens because the air inside the bottle and its narrow opening behave somewhat like a mass attached to a spring. When sound at the right frequency excites a specially designed resonator, those vibrations become much stronger, forcing air rapidly through the opening. The resulting airflow can form a directional jet powerful enough to generate thrust.
The researchers set out to harness the same physics behind Helmholtz resonance as an unconventional propulsion method for microrobots.
The researchers designed tiny cavities that take advantage of the same principle. When sound hits one of these resonators at just the right frequency, the air in its narrow neck begins moving rapidly back and forth.
Because that airflow is slightly uneven as it enters and exits, it creates a small but focused jet of air. That jet produces thrust, giving the resonator enough force to help move or even lift a microrobot.
The team 3D-printed resonators ranging from centimeter to micrometer scales, designing them to respond to frequencies between roughly 200 hertz and 40 kilohertz. Experiments showed that larger cavities generally produced greater thrust, while the geometry and thickness of the resonator’s neck played a particularly important role in determining performance.
Importantly, researchers could tune different resonators to different frequencies. That means sound does more than supply power; frequency can effectively serve as a control signal.
The researchers demonstrated the concept using miniature boats equipped with acoustic resonators. One early prototype carried a resonator tuned to 1.2 kilohertz and moved only when exposed to sound at that frequency.
More advanced versions used separate resonators for propulsion and steering, allowing the researchers to guide a boat around obstacles remotely and along a figure-eight course with a mean tracking error of just 5.70 millimeters.
The team also showed that an external speaker is not always necessary. By attaching small vibration transducers directly to resonators, they could send sound through the robot’s structure itself.
This approach allowed the researchers to build a fully integrated boat equipped with its own battery, control electronics, and acoustic transducers. Bluetooth commands activated resonators tuned for propulsion and steering, with a total communication latency of about 30 milliseconds. The boat successfully traced the letters “EPFL,” navigated past obstacles, and could be steered back on course after researchers deliberately disturbed it by blowing air or physically pushing it.
However, shrinking the technology into flying microrobots provided the study’s most striking demonstration.
One microflier consisted of three microscopic resonators operating at 40 kilohertz and weighed only about 150 micrograms. Focused ultrasound caused each resonator to eject a tiny jet of air downward. Together, the three produced a thrust-to-weight ratio of approximately 4.9. The machine accelerated upward, climbed roughly 12 millimeters before settling around seven millimeters above its starting position.
A second design took a different approach. Instead of pointing the acoustic jets downward, the researchers used them to spin a rotor fitted with tiny aerodynamic blades. The entire aircraft weighed 184 micrograms.
Once exposed to ultrasound, the rotor accelerated to approximately 13,000 rpm. Its blades generated enough aerodynamic thrust for takeoff before settling to roughly 6,500 rpm while hovering.
Turning the device upside down prevented it from ascending, helping confirm that aerodynamic thrust, rather than acoustic radiation pressure alone, enabled flight.
Researchers demonstrated unconstrained flight with both microrobot designs. The direct-thrust version climbed rapidly but sometimes flipped in the air. The spinning version was more stable, apparently because its swift rotation provided a gyroscopic stabilizing effect similar to that found in helicopters and spinning discs.
Ultimately, the experiments remain proof-of-concept demonstrations rather than prototypes of free-ranging autonomous microrobots. Airborne propulsion requires external acoustic hardware capable of keeping a sufficiently strong sound field focused on a tiny moving object. That essentially limits the robot’s operating area. Putting the acoustic source onboard offers greater autonomy but might significantly increase the robot’s weight.
The current flying system also operates at a single 40-kilohertz frequency, restricting how independently its resonators can be controlled. The researchers suggest future multifrequency ultrasonic arrays could selectively activate different resonators, allowing small aircraft to steer and coordinate their movement through sound alone.
Further miniaturization is technically possible. Modern 3D nanoprinting can fabricate structures with resolutions around 700 nanometers, possibly allowing resonators only several micrometers across. However, at those scales, viscous forces become increasingly important and may dramatically reduce thrust, meaning simply shrinking the existing design may eventually stop working.
Still, the wider concept could go beyond flying machines. Researchers envision flexible structures containing many differently tuned resonators that can bend, vibrate, or change shape depending on the applied sound frequency, possibly resulting in shape-morphing microrobots and mechanical metamaterials.
“Our work extends the concept of acoustic manipulation toward active propulsion by harnessing cavity resonance to generate directional thrust and controlled motion,” the researchers write. “This approach broadens the scope of airborne acoustic actuation toward small-scale robots capable of autonomous operation in open environments.”
The recent study, “Acoustic Resonators as Wireless Actuators in Air for Small-Scale Robots,” was published in Science Advances.
Tim McMillan is a retired law enforcement executive, investigative reporter and co-founder of The Debrief. His writing typically focuses on defense, national security, the Intelligence Community and topics related to psychology. You can follow Tim on Twitter: @LtTimMcMillan. Tim can be reached by email: tim@thedebrief.org or through encrypted email: LtTimMcMillan@protonmail.com
Samsung smartphones are known for their excellent camera performance, but the camera shutter sound can sometimes be inconvenient, especially when taking photos in quiet environments such as libraries, meetings, museums, or during personal moments.
Depending on your Samsung phone model, region, and software version, the method for disabling the camera sound may vary. This guide explains the common ways to turn off or reduce the camera shutter sound on Samsung Galaxy devices.
The camera shutter sound is designed to provide an audible confirmation that a photo has been captured.
However, in some countries and regions, smartphone manufacturers are required by law to keep the shutter sound enabled to protect privacy and prevent unauthorized photography.
Because of these regional regulations:
If you cannot find the option, it may be restricted by your device’s region settings.
On many Samsung Galaxy phones, you can turn off the shutter sound directly from the Camera app.
Follow these steps:
Launch the built-in Camera application on your Samsung phone.
Tap the gear icon (Settings) in the top-left or top-right corner.
Look for:
Shutter sound
or
Camera sounds
Toggle the option off.
After disabling it, taking photos will no longer produce the camera shutter sound.
Note: This option is not available on every Samsung model.
If your Samsung phone does not provide a shutter sound option, you can try muting system sounds.
On many Galaxy devices, the shutter sound follows the system volume settings.
Another simple method is reducing the system sound volume.
Settings → Sounds and vibration
Volume
System volume
to the lowest level.
Then test the camera again.
Depending on your Samsung model, the shutter sound may disappear.
Samsung’s Modes and Routines feature allows automatic sound control.
You can create a routine that switches your phone to silent mode when entering specific locations or situations.
For example:
Settings → Modes and Routines
Routines
This can automatically disable camera sounds when needed.
If the Samsung Camera app does not allow shutter sound control, some third-party camera applications may offer additional options.
Examples include:
These apps may provide settings such as:
However, availability depends on your phone model and Android version.
Some Samsung phones sold in regions where shutter sounds are mandatory cannot disable the sound.
Advanced users sometimes change the device region or firmware version to another market where disabling the shutter sound is allowed.
However, this method is not recommended for most users because it may:
Always check your local laws before changing regional settings.
For Galaxy S models:
If the option is missing:
Foldable Galaxy phones usually follow the same camera settings:
Camera → Settings → Shutter sound
If unavailable:
Budget and mid-range Galaxy A phones may have different software versions.
Try:
If the shutter sound cannot be turned off, possible reasons include:
Some countries require phones to make a camera sound.
Carrier-specific software may remove the option.
New One UI versions may change camera settings locations.
Not all Samsung Galaxy models support shutter sound control.
It depends on your phone model and region. Some devices allow it through Camera settings, while others only allow muting through sound modes.
Not always. Some Samsung phones still keep the shutter sound active due to regional restrictions.
Screenshot sounds are controlled separately and may also depend on your region settings.
No. Turning off the shutter sound only changes audio feedback and does not affect camera performance or image quality.
Turning off the camera shutter sound on a Samsung phone is usually simple if your device supports the option. Start by checking:
Camera App → Settings → Shutter Sound
If that option is unavailable, try:
Keep in mind that some Samsung phones sold in certain regions are required to keep the shutter sound enabled, so the available options may depend on your device model and location.
The post How to Turn Off the Camera Shutter Sound on a Samsung Phone: Complete Guide appeared first on IGeeKphone China Phone, Tablet PC, VR, RC Drone News, Reviews.
A JBL lançou hoje no Brasil os Endurance Pace. Apresentados no início deste ano, eles são uma opção interessante para quem pratica algum esporte ou exercícios físicos, e contam com recursos projetados especialmente para esse tipo de atividade.
Um dos maiores diferenciais desse produto é a tecnologia OpenSound, capaz de entregar áudio de grande qualidade sem bloquear o canal auditivo — num formato que é indicado para quem não curte fones de ouvido do tipo intra-auricular.
O driver dinâmico sensível de 18x11mm oferece agudos nítidos e cristalinos, médios encorpados e ricos, com um algoritmo de reforço de graves adaptativo. Devido ao formato e à tecnologia, o som direcional é reproduzido com o mínimo de vazamento, mantendo os fones encaixados por fora e confortáveis durante o uso.
Com uma armação leve (de metal com memória de titânio), que mantém os fones confortáveis durante o dia, o produto também conta com classificação IP68 e pode ser submerso em água doce por até 30 minutos, a mais de um metro de profundidade.
Os fones também possuem captação sonora avançada (graças aos seus dois microfones com tecnologia beamforming), bem como uma bateria com autonomia de até 10 horas e capaz de prover até 4 horas de uso com uma carga de 10 minutos.
Com um preço sugerido de R$400, os JBL Endurance Pace já podem ser adquiridos na loja online brasileira da JBL.
via TudoCelular.com
Já estão disponíveis no Brasil dois novos fones de ouvido sem fio da JBL: os Live Beam 4 e os Live Flex 4, expandindo a linha de modelos equipados com o Smart Charging Case — estojo com tela sensível ao toque que permite acessar funções dos fones facilmente.
Com poucos gestos, é possível controlar a reprodução, ajustar o volume, gerenciar os níveis de controle de ruído, alterar as configurações e acompanharas informações essenciais diretamente na tela do estojo.
Segundo a JBL, os fones Live Beam 4 foram projetados para quem busca um encaixe mais isolado e seguro, combinando conforto e estabilidade. O modelo oferece até 48 horas de reprodução, com até 12 horas nos fones e mais 36 horas no estojo, além de resistência à água e poeira com certificação IP55.
Já os fones Live Flex 4 têm um formato aberto e leve, desenvolvido para longos períodos de uso. Com autonomia de até 50 horas de reprodução, com até 10 horas nos fones e mais 40 horas no estojo, o modelo também conta com proteção IP54 contra água e poeira, mantendo a versatilidade para diferentes ambientes e atividades.
Ambos os novos modelos oferecem o JBL Signature Sound, tecnologia de áudio de alta resolução da marca que oferece graves profundos e detalhes precisos para diferentes estilos de conteúdo.
Os dois modelos contam ainda com seis microfones e tecnologia de redução de ruído com inteligência artificial para ajudar a manter conversas mais claras e naturais, mesmo em ambientes movimentados. Já os recursos Smart Ambient permitem manter a percepção do que acontece ao redor quando necessário.
Os fones já estão disponíveis no site da JBL, ambos por R$1.000, nas cores preta, prata, azul, champagne, verde, laranja e lilás.
Reset PRAM on Mac is one of those troubleshooting steps that has survived decades of Apple hardware, old support forums and emergency calls to the family member who “knows computers.” The name sounds far more technical than the procedure, which involves restarting an Intel-based Mac while holding four keys.
The reset can help when a Mac remembers the wrong basic settings. It may select an unexpected startup disk, return to an incorrect display resolution, use an unusual sound level or keep other hardware-related preferences that refuse to behave normally.
It is not a speed boost, a deep system repair or a magical cure for every Mac problem. Resetting PRAM will not clear storage, repair a damaged app or make an aging MacBook suddenly feel new. It is a focused fix for a small collection of settings stored outside the usual macOS preferences.
There is also one major limitation: the familiar keyboard shortcut applies only to Intel-based Macs. Apple silicon models handle this memory differently and do not require the same manual reset.
PRAM stands for Parameter Random-Access Memory. It was the small amount of memory older Macs used to preserve certain settings while the computer was turned off.
Apple later moved to NVRAM, or nonvolatile random-access memory, but the two names remain closely connected in Mac troubleshooting. Users still search for PRAM reset, while Apple’s current documentation usually calls the procedure an NVRAM or PRAM reset.
The stored information can include the selected startup disk, speaker volume, screen resolution and other low-level settings. When that information becomes incorrect or behaves unpredictably, resetting it allows the Mac to rebuild the relevant preferences.
Nothing dramatic happens to personal data. Documents, photos, apps, emails and user accounts remain untouched. Some settings may return to their defaults, which is the point of the reset.
Reset PRAM on Mac when the problem appears connected to startup or hardware preferences rather than normal app use.
A Mac that repeatedly chooses the wrong startup disk is a good candidate. So is an Intel Mac that starts with an unexpected sound level or returns to a strange display resolution after every restart.
The procedure may also help when the date, time zone or other basic startup settings act strangely, although modern macOS versions usually manage those automatically.
It is less useful when Safari is slow, an app keeps crashing or the Mac is nearly out of storage. Those problems have different causes. Closing apps, installing updates or freeing storage will usually do more than resetting a small bank of startup memory.
The distinction keeps the old troubleshooting step useful without turning it into Mac folklore prescribed for every symptom.
Before using the shortcut, confirm whether the Mac has an Intel processor or Apple silicon.
Apple menu > About This Mac
Look for a line labeled Chip or Processor. An M-series chip identifies Apple silicon. A processor name containing Intel means the traditional reset applies.
This check prevents a common misunderstanding. Holding Option, Command, P and R during startup on an Apple silicon Mac does not perform the old PRAM reset. The shortcut belongs to Intel startup behavior. Apple’s current startup-key guide lists it specifically among key combinations for Intel-based Macs.
Apple silicon Macs check and manage stored startup information through their newer boot system. A normal shutdown and restart is usually the first step when one develops unusual basic behavior.
The useful guidance is brief:
Shut down the Mac completely.
Option + Command + P + R
Keep the four keys pressed for approximately 20 seconds, then release them and allow the Mac to start normally.
Older Macs may play the startup sound more than once. On some newer Intel models, the Apple logo may appear and disappear during the process.
The timing is the only slightly awkward part. The keys need to be pressed immediately after the Mac begins starting. Waiting until the login window appears is too late.
After the Mac starts, check the setting that caused the problem. The startup disk, volume or display configuration may need to be selected again because the reset cleared the previous preference.
Most users will notice nothing beyond the original problem hopefully disappearing. The Mac does not present a dramatic confirmation screen or announce that PRAM has been purified.
Instead, a few stored settings may return to their defaults. The speaker volume may change. The preferred startup disk may need to be chosen again. A display may return to its standard resolution. Time-zone information may need a moment to update.
That understated behavior is normal. A successful reset is less like reinstalling macOS and more like asking the Mac to forget a handful of stubborn instructions.
Apple also uses an NVRAM reset as one of the preparation steps for certain Intel Macs before they are sold or transferred, since the procedure clears stored user settings from memory.
Apple silicon changed the Mac startup process along with performance, power efficiency and system security. The older Intel keyboard combination no longer controls the same reset behavior.
For an M-series Mac showing unusual startup settings, begin with a full shutdown rather than repeatedly trying the old shortcut.
Apple menu > Shut Down
Wait briefly after the screen turns completely black, then turn the Mac back on.
If the problem involves selecting a startup disk or reaching recovery tools, hold the power button while the Mac starts until startup options appear. Apple documents this power-button process as the route into startup options on Apple silicon models. (Apple Support)
That is usually enough guidance for a light troubleshooting article. Recovery, diagnostics and deeper repair steps belong to more serious startup problems, not every incorrect volume level or display setting.
A PRAM reset can fail to change anything because the problem was never stored in PRAM or NVRAM.
A slow Mac may be running too many apps. A browser may have dozens of heavy tabs. A startup disk may be almost full. A damaged cable may cause display problems. A weak battery may cause shutdowns. A broken speaker will not repair itself because four keys were held during startup.
If the symptom continues, return to the problem itself rather than repeating the reset indefinitely.
Check the related setting in System Settings. Install macOS updates. Restart the affected app. Disconnect unnecessary accessories. Confirm that enough storage is available. Persistent hardware behavior may require Apple Diagnostics or professional support.
The reset should be treated as one useful step, not an annual Mac ritual.
Reset PRAM on Mac remains relevant because Intel models are still in use across homes, schools and businesses. Many continue to work well, and their owners may eventually encounter the sort of odd startup preference that this procedure was designed to clear.
The method is simple, safe for personal files and quick enough to try when the symptoms fit. Its usefulness comes from being specific.
An Intel Mac remembering the wrong startup disk or display setting may benefit. A Mac with an unrelated software or hardware problem will need another answer.
The four-key shortcut has survived because it occasionally solves a strange problem in about 20 seconds. That is a good troubleshooting tool. It just should not be asked to perform miracles.
The post Reset PRAM on Mac to Fix Strange Settings appeared first on AppleMagazine.
A wearable bioelectronic device increased REM sleep in real-world trials without invasive surgery or medication. A restless night can leave more than fatigue behind. REM sleep plays a central role in emotional processing, stress adaptation and mental recovery, and persistent disruptions to this stage have been linked to conditions including depression, anxiety and post-traumatic stress [...]
Ultrasonic espresso’ made with cold water and high-frequency sound waves uses less energy than the traditional version – and taste tests show it’s just as good.
A new soft ultrasound patch is designed to provide long-term, hands-free monitoring of fetal health in real time. Engineers at the University of California, San Diego, have developed a soft, wearable ultrasound patch that can continuously monitor a fetus for hours at a time while maintaining reliable performance even as the fetus and umbilical cord [...]
For more than a century, musicians have maintained that the way a pianist touches a key influences the sound that emerges. Many scientists, however, have argued that after the hammer strikes the string, the instrument itself determines the outcome, making the pianist’s touch irrelevant.
Now, a recent study published in the Proceedings of the National Academy of Sciences provides some of the strongest evidence yet in support of the musicians’ perspective.
A research team led by Dr. Shinichi Furuya of the NeuroPiano Institute and Sony Computer Science Laboratories developed a custom sensor system called HackKey. This system can record the movement of all 88 piano keys at 1,000 frames per second, with a spatial precision of 0.01 millimeters. The team invited 20 internationally recognized pianists to play notes while intentionally aiming for contrasting timbres, such as bright versus dark and light versus heavy. Listeners were able to distinguish among the different timbres, even individuals with no experience playing the piano.
The researchers identified a series of micro-movements beneath each keystroke. These movements are so subtle that they are almost impossible to see, but precise enough for listeners to perceive differences in sound.
Small changes in how quickly a key accelerates, slight overlaps between notes, and variations in the speed of initial contact with the key all influenced how listeners described the resulting sound. When each of these factors was adjusted individually, the perceived timbre changed. Adjusting a single movement feature was enough to reliably change how listeners perceived timbre. The results show that touch has a direct effect on sound, independent of factors such as volume or tempo.
The study describes these micro-movements as a motor skill developed through years of advanced training. The researchers call the emerging science of mapping movement to musical experience “dynaformics.”
The debate over whether touch can alter piano timbre dates back to at least the early 1900s, when music educators began discussing what distinguishes one performer’s sound from another. The piano’s mechanical action appeared to support the skeptics, since the hammer, once released, moves independently before striking the string and is not directly contacted by the pianist’s finger.
As a result of this mechanical process, many acousticians concluded that any reported differences in tone were psychological, influenced by context, volume, or timing rather than by touch. Musicians maintained their position but did not have the scientific tools to prove it.
To settle this debate, Furuya’s team developed a custom biometric contact-sensing system called HackKey, capable of recording the movement of all 88 piano keys at 1,000 frames per second with sub-millimeter precision. The system captured in-depth piano movement data that previous technology could not. For the first time, researchers could observe the specific actions of elite pianists and relate those movements to listeners’ descriptions of sound.
Piano teachers have often used general phrases like “play warmer” or “use a softer touch” because the specific movements that create certain sound qualities were not well understood. This study now offers a guide to those movements.
Future training tools may allow students to see precisely what their fingers are doing when a note is played successfully or not. Instead of relying on a teacher’s metaphor, students could compare their own keystrokes to a standard and work to improve their technique. The researchers suggest that this approach could make expressive technique easier to teach and visualize, especially for students who find it difficult to translate verbal instructions into physical actions.
The research may also apply to rehabilitation, robotics, and human-computer interaction. Discovering that small differences in movement can shape auditory perception offers new insight into how the brain links movement and sensory experience. Some researchers are exploring whether systems based on expressive musical movement could help patients recover dexterity and coordination after injury.
Most scientific research on music has focused on elements that are easier to measure, like pitch, loudness, and rhythm. Timbre, or the quality or “color” of a sound that makes one instrument or voice different from another, has been harder to measure. This study offers a new way to understand the mechanics behind this concept. The findings suggest that some of the most expressive parts of music come from movements too small to see, developed through years of practice.
Austin Burgess is a writer and researcher with a background in sales, marketing, and data analytics. He holds an MBA, a Bachelor of Science in Business Administration, and a data analytics certification. His work focuses on breaking scientific developments, with an emphasis on emerging biology, cognitive neuroscience, and archaeological discoveries.
A wearable ultrasound patch regulates heartbeats from outside the chest, eliminating invasive surgery.
New research led by scientists from the French National Institute for Agriculture, Food, and Environment (INRAE) suggests cows (Bos taurus taurus) can distinguish between known and unknown people, and even match a familiar voice to the correct face.
The post Cows Can Recognize Familiar Human Faces, New Study Finds appeared first on Sci.News: Breaking Science News.
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