Optical sensors improve railway safety

A string of fiber-optic sensors running along a 36-km stretch of high-speed commuter railroad lines connecting Hong Kong to mainland China has taken more than 10 million measurements over the past few years in a demonstration that the system can help safeguard commuter trains and freight cars against accidents.

Attuned to the contact between trains and tracks, the sensors can detect potential problems like excessive vibrations, mechanical defects or speed and temperature anomalies. The system is wired to warn train operators immediately of such problems so that they can avoid derailments or other accidents, said Hwa-yaw Tam of the Hong Kong Polytechnic University, who will describe the technology and its test run next week at The Optical Society's (OSA) Annual Meeting, Frontiers in Optics (FiO) 2013, being held Oct. 6-10 in Orlando, Fla.

At least 30 times during the seven-year period, the system detected anomalous vibrations, Tam said. In a few cases, the vibrations turned out to be early warnings of dangerous emerging conditions that could have led to train wrecks. In some cases, vibration due to the use of the wrong type of lubrication oil in axle boxes was detected. The fiber-optic sensor system was designed for maintenance purposes and saves the rail company about $250,000 every year in maintenance costs.

“Using just this one type of technology, we are able to measure many things,” Tam said. “This technology is perfect for railway systems.” He added that it costs less than a third the price of other warning systems, which typically require data to be integrated from a half dozen different types of monitoring systems.

The system is now being installed in all commuter train routes in Hong Kong and will soon be rolled out in railways in parts of Singapore and Australia. With regular speeds for some of the trains in China topping out above 300 km per hour, the need for effective safety measures is profound, Tam said.

Worldwide, the rail industry is undergoing a major development boom, especially in places like China where tens of thousands of kilometers of new high-speed lines are planned for the next decade at an estimated cost of hundreds of billions of dollars.

How the System Works

The basis for the new sensor system is a technology developed in the 70s and 80s known as a Fiber Bragg grating, a type of sensor that reflects narrow spectra of light whose wavelengths shift due to temperature/strain variation. Coupling fiber Bragg gratings with another device known as mechanical transducers allows pressure, acceleration and other parameters to be measured.

The sensors are imbedded in mechanical compartments of a train or along the tracks. If there is a defect, like a sudden break in the rails or excessive vibrations because the weight of the train is off balance, those changes will alter the reflection spectra of FBGs in a detectable way.

The system is advantageous because it is all-optical, allowing the passive fiber Bragg grating sensors to monitor conditions along a train route, Tam said. It also relies exclusively on optical detection and communication, so there are no problems with electromagnetic interference from power lines that run parallel to many modern rail lines.

Presentation FW2I.3, “Distributed Optical Fiber Sensing Networks for Railway Monitoring,” takes place Wednesday, Oct. 9 at 11:30 a.m. EDT at the Bonnet Creek Ballroom, Salon X at the Hilton Bonnet Creek in Orlando, Fla.

PRESS REGISTRATION: A press room for credentialed press and analysts will be located in the Hilton Bonnet Creek, Sunday through Thursday, Oct. 6-10. Those interested in obtaining a press badge for FiO should contact OSA's Lyndsay Meyer at 202.416.1435 or lmeyer@osa.org.

About the Meeting

Frontiers in Optics (FiO) 2013 is the Optical Society's (OSA) 97th Annual Meeting and is being held together with Laser Science XXIX, the annual meeting of the American Physical Society (APS) Division of Laser Science (DLS). The two meetings unite the OSA and APS communities for five days of quality, cutting-edge presentations, fascinating invited speakers and a variety of special events spanning a broad range of topics in optics and photonics—the science of light—across the disciplines of physics, biology and chemistry. An exhibit floor featuring leading optics companies will further enhance the meeting. More information at http://www.FrontiersinOptics.org.

About OSA

Founded in 1916, The Optical Society (OSA) is the leading professional society for scientists, engineers, students and business leaders who fuel discoveries, shape real-world applications and accelerate achievements in the science of light. Through world-renowned publications, meetings and membership programs, OSA provides quality research, inspired interactions and dedicated resources for its extensive global network of professionals in the optics and photonics field. For more information, visit http://www.osa.org.

Media Contact

Lyndsay Meyer EurekAlert!

Weitere Informationen:

http://www.osa.org

Alle Nachrichten aus der Kategorie: Physics and Astronomy

This area deals with the fundamental laws and building blocks of nature and how they interact, the properties and the behavior of matter, and research into space and time and their structures.

innovations-report provides in-depth reports and articles on subjects such as astrophysics, laser technologies, nuclear, quantum, particle and solid-state physics, nanotechnologies, planetary research and findings (Mars, Venus) and developments related to the Hubble Telescope.

Zurück zur Startseite

Kommentare (0)

Schreib Kommentar

Neueste Beiträge

Scientists advance understanding of blood-brain barrier health

Fralin Biomedical Research Institute scientists’ finding has implications for brain diseases. Hard skulls help protect our brains from physical injuries. In addition to a tough outer shell, brains have internal…

Why there is no speed limit in the superfluid universe

Physicists from Lancaster University have established why objects moving through superfluid helium-3 lack a speed limit in a continuation of earlier Lancaster research. Helium-3 is a rare isotope of helium,…

The right formula for scaling production of promising material to decontaminate water

An international team of researchers have found a way to refine and reliably produce an unpredictable and hard-to-control material that could impact environmental conservation, energy and consumer electronics. The material,…

By continuing to use the site, you agree to the use of cookies. more information

The cookie settings on this website are set to "allow cookies" to give you the best browsing experience possible. If you continue to use this website without changing your cookie settings or you click "Accept" below then you are consenting to this.

Close