Video cameras continue to gain widespread use to monitor human activities for surveillance, health care, home use and more, but there are privacy and environmental limitations in how well they work. Acoustical waves, such as sounds and other forms of vibrations, are an alternative medium that may bypass those limitations.
Unlike electromagnetic waves, such as those used in radar, acoustical waves can be used not only to find objects but also to identify them. As described in a new paper in the May 28 issue of Applied Physics Letters, from AIP Publishing, the researchers used a two-dimensional acoustic array and convolutional neural networks to detect and analyze the sounds of human activity and identify those activities.
“If the identification accuracy is high enough, a large number of applications could be implemented,” said Xinhua Guo, associate professor at Wuhan University of Technology. “For example, a medical alarm system could be activated if a person falls at home and it is detected. Thus, immediate help could be provided and with little privacy leaked at the same time.”
By using a two-dimensional acoustic array with 256 receivers and four ultrasonic transmitters, the researchers were able to gather data related to four different human activities — sitting, standing, walking and falling. They used a 40-kilohertz signal to bypass any potential contamination from ordinary room noise and distinguish it from the identifying sounds.
Their tests achieved an overall accuracy of 97.5% for time-domain data and 100% for frequency-domain data. The scientists also tested arrays with fewer receivers (eight and four) and found them to produce results with lower accuracy of the human activity.
Guo said acoustic systems are a better detection device than vision-based systems because of the lack of widespread acceptance of cameras due to privacy issues. In addition, low lighting or smoke can also hamper vision recognition, but sound waves are not affected by those special environmental situations.
“In future, we will go on studying complex activity and situation of random positioning,” Guo said. “As we know, human activities are complicated, taking falling as an example, and can present in various postures. We are hoping to collect more datasets of falling activity to reach higher accuracy.”
Guo said they will be experimenting with various numbers of sensors and their effectiveness in detecting and determining human activities. He said there is an optimal number for the array that would make this viable for commercial and personal use in homes and buildings.
The Latest on: Acoustical waves
via Google News
The Latest on: Acoustical waves
- NanoVibronix Issues Letter to Shareholderson January 19, 2021 at 10:01 pm
NanoVibronix, Inc ., (NASDAQ: NAOV), a medical device company that produces the UroShield®, PainShield® and WoundShield® Surface Acoustic Wave (SAW) Portable Ultrasonic Therapeutic Devices, today ...
- Frogs in South America Wave to Attract Mates - Studyon January 19, 2021 at 1:47 pm
Frogs living near noisy waterfalls in South America wave to attract mates, a new study reveals. In field studies, a US expert studied the glass frog (Sachatamia orejuela), which is found on slippery ...
- Acoustic Wave Sensors Market Potential Targets And Recommendations With New Solutions| Honeywell International Inc. and Seimens AGon January 19, 2021 at 9:26 am
Prudour Pvt. Ltd –:Market.us, one of the worlds leading by prominent market research firms has | eTurboNews | Trends | Travel News Online | ...
- Frogs living near roaring waterfalls wave hello to attract mateson January 18, 2021 at 7:45 am
Video footage reveals a male glass frog specimen showing off with a casual flap of the hand, a wave of its foot and a friendly nod of the head in the hope of being noticed.
- Glass frogs living near roaring waterfalls wave hello to attract mateson January 17, 2021 at 1:33 pm
A conservationist has discovered that the glass frog Sachatamia orejuela can be added to the list of species that make use of visual cues in response to their acoustic environments. This is the first ...
- Secrets Behind Sunquakes May Lurk Beneath the Solar Surfaceon January 16, 2021 at 11:59 pm
A secret behind the workings of sunquakes – seismic activity on the Sun during solar flares – might be hidden beneath the solar surface. These earthquake-like events release acoustic energy in the ...
- It's rare in the medical world to say no side effects, but that's the case for this E.D. treatmenton January 14, 2021 at 10:45 am
It's rare in the medical world to say no side effects, especially when you're talking about erectile dysfunction. Guys are used to the side effects of the pill, like headaches and blurred vision. But ...
- Jake Larkin makes acoustic debut at RCBC Fridayon January 14, 2021 at 5:15 am
Up and coming Rockmart native Jake Larkin will make his acoustic debut Friday at Rome City Brewing Company. “This will be Luke’s RCBC debut,” said Jay Shell. “We are excited to have him. He’ll be ...
- Engineer awarded NSF grant to investigate acoustic graphene propertieson January 13, 2021 at 5:02 am
An illustration of bilayer graphene showing the characteristic Moiré pattern that results from the rotation of one layer.Image: Nikhil Gerard ...
- Body and Ocean Scanning Acoustic Frequency Combs Made Using Fish Tank Bubbleson January 11, 2021 at 3:48 am
Optical Frequency Combs have proved such a valuable tool for scientists their invention won the 2005 Physics Nobel Prize. Physicists are seeking a counterp ...
via Bing News