Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

“Virtual Periscope” Sees Above-Surface/Airborne Objects From Underwater View

30.04.2014

Researchers modeled virtual periscope on astronomers’ technology used to counter blurring and distortion caused by layers of atmosphere when viewing stars

“Up periscope!” may become a submarine commander's outdated order, thanks to a team of Technion-Israel Institute of Technology researchers who have developed a new technology for viewing objects above the water's surface without a periscope poking its head above the waves.

The technology behind a submerged, “virtual periscope” will be introduced in a presentation at the IEEE International Conference on Computational Photography, held May 2-4, 2014 in Santa Clara, Calif. ( http://www.iccp14.org/ ])

Associate Professor Yoav Y. Schechner, of the Technion Department of Electrical Engineering, and colleagues, developed the virtual periscope called “Stella Maris” (Stellar Marine Refractive Imaging Sensor). The heart of the underwater imaging system is a camera, a pinhole array to admit light (a thin metal sheet with precise, laser-cut holes), a glass diffuser, and mirrors. Sunrays are projected through the pinholes to the diffuser, which is imaged by the camera, beside the distorted object of interest. The latter is then corrected for distortion.

“Raw images taken by a submerged camera are degraded by water-surface waves similarly to degradation of astronomical images by our atmosphere. We borrowed the concept from astronomers who use the Shack-Hartmann astronomical sensor on telescopes to counter blurring and distortion caused by layers of atmosphere,” explains Schechner. “Stella Maris is a novel approach to a virtual periscope as it passively measures water and waves by imaging the refracted sun.”

The unique technology gets around the inevitable distortion caused by the water-surface waves when using a submerged camera, according to Schechner, because of the sharp refractive differences between water and air, random waves at the interface present distortions that are worse than the distortion atmospheric turbulence creates for astronomers peering into space.

“When the water surface is wavy, sun-rays refract according to the waves and project onto the solar image plane,” explains Schechner. “With the pinhole array, we obtain an array of tiny solar images on the diffuser.” When all of the components work together, the Stella Maris system acts as both a wave sensor to estimate the water surface, and a viewing system to see the above surface image of interest through a computerized, “reconstructed” surface.

The Stella Maris virtual periscope is just the latest technology developed by the researchers, who have also found ways to exploit “underwater flicker,” i.e., random change of underwater lighting, caused by the water surface wave motion. Members in the Schechner Hybrid Imaging Lab (http://webee.technion.ac.il/~yoav/lab-and-group/) turned the tables on underwater flicker and used the natural rapid and random motion of the light beams to obtain three-dimensional mapping of the sea floor.

According to the developers, the virtual periscope may have potential uses in addition to submarines, where they could reduce the use of traditional periscopes that have been in use for more than a century. Submerged on the sea floor, Stella Maris could be useful for marine biology research where and when viewing and imaging both beneath and above the waves simultaneously is important. Stella Maris could, for example, monitor the habits of seabirds as they fly, then plunge into water and capture prey.

“There are many ways to advance the virtual periscope,” says Schechner, who adds that while the system requires sunlight, they are currently working on a way to gather enough light from moonlight or starlight to be able to use the system at night.

Also contributing to this research were current graduate student Marina Alterman and former graduate student Dr. Yohay Swirski (who is now working in industry). The research was conducted in Schechner's Hybrid Imaging Lab in the Technion Department of Electrical Engineering.

The Technion-Israel Institute of Technology is a major source of the innovation and brainpower that drives the Israeli economy, and a key to Israel's renown as the world's “Start-Up Nation.” Its three Nobel Prize winners exemplify academic excellence. Technion people, ideas and inventions make immeasurable contributions to the world including life-saving medicine, sustainable energy, computer science, water conservation and nanotechnology. The Joan and Irwin Jacobs Technion-Cornell Innovation Institute is a vital component of Cornell NYC Tech, and a model for graduate applied science education that is expected to transform New York City's economy.

American Technion Society (ATS) donors provide critical support for the Technion - more than $1.9 billion since its inception in 1940. Based in New York City, the ATS and its network of chapters across the U.S. provide funds for scholarships, fellowships, faculty recruitment and chairs, research, buildings, laboratories, classrooms and dormitories, and more.

Kevin Hattori | newswise
Further information:
http://www.ats.org

More articles from Physics and Astronomy:

nachricht Innovative LED High Power Light Source for UV
22.06.2017 | Omicron - Laserage Laserprodukte GmbH

nachricht Spin liquids − back to the roots
22.06.2017 | Universität Augsburg

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

Im Focus: Optoelectronic Inline Measurement – Accurate to the Nanometer

Germany counts high-precision manufacturing processes among its advantages as a location. It’s not just the aerospace and automotive industries that require almost waste-free, high-precision manufacturing to provide an efficient way of testing the shape and orientation tolerances of products. Since current inline measurement technology not yet provides the required accuracy, the Fraunhofer Institute for Laser Technology ILT is collaborating with four renowned industry partners in the INSPIRE project to develop inline sensors with a new accuracy class. Funded by the German Federal Ministry of Education and Research (BMBF), the project is scheduled to run until the end of 2019.

New Manufacturing Technologies for New Products

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

A new technique isolates neuronal activity during memory consolidation

22.06.2017 | Life Sciences

Plant inspiration could lead to flexible electronics

22.06.2017 | Materials Sciences

A rhodium-based catalyst for making organosilicon using less precious metal

22.06.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>