Wireless Structural Monitoring System Deployed in Korea
Illinois researchers have developed an inexpensive, wireless means for continuous and reliable structural health monitoring and successfully deployed their system last summer at full scale on the new Jindo Bridge in South Korea. A joint project between the University of Illinois at Urbana-Champaign, KAIST in Korea, and the University of Tokyo, it is the first dense deployment of a wireless sensor network on a cable-stayed bridge and the largest of its kind for civil infrastructure to date.
The researchers—part of the Illinois Structural Health Monitoring Project (ISHMP) led by Professor Bill Spencer of the Department of Civil and Environmental Engineering and Professor Gul Agha of the Department of Computer Science—designed, developed, and tested sensors that can be manufactured very cheaply and still produce the high-fidelity data required for structural health monitoring. Their research has also produced a customizable software framework that simplifies the development of structural health monitoring applications for smart sensor platforms. In combination, their sensors and software create an integrated framework that can be utilized by most civil engineers without the need for extensive background in electrical engineering or computer science. More than 40 institutions throughout the world are now using the ISHMP framework, says CEE Professor Bill Spencer.
“It’s becoming the de facto standard for wireless sensing of civil infrastructure,” Spencer says.
Structural health monitoring is an emerging field that combines civil engineering knowledge with developments in sensor technology, information management, and networking technologies. The goal is to achieve a more reliable alternative to traditional structure inspection techniques. Until now, though, its usefulness was limited by concerns about cost and effectiveness.
“Manual inspection of bridges costs millions of dollars, is relatively unreliable, and can only be carried out infrequently,” Spencer says. “Some real-world structural health monitoring deployments using wired sensors have have been able to provide detailed information about the state of civil infrastructure. However, the enormous expense of installing traditional monitoring systems has significantly limited such deployments.”
The Illinois team’s framework addresses this issue by employing dense arrays of wireless smart sensors designed to record and transmit complex, high-fidelity data cheaply and efficiently. The team’s technology employs concurrent and distributed real-time processing to overcome the limitations inherent in traditional centralized approaches.
“The traditional centralized approach for structural health monitoring is not feasible with moderate to large numbers of sensors; tremendous amounts of data must be sent to such a central station, requiring expensive, difficult-to-install wired networking and introducing a single point of failure,” Agha says. “Our research in distributed structural health monitoring using wireless sensor networks overcomes these problems and promises a robust, significantly lower-cost safer alternative to traditional structure inspection techniques.”
Others who have contributed to this project include: Shinae Jang, CEE Ph.D. student; Hongki Jo, CEE Ph.D. student; Jennifer A. Rice (MS 05, PhD 09), assistant professor at Texas Tech University; Robin Kim, CEE Ph.D. student; Sung-Han Sim, CEE Ph.D. student; Parya Moinzadeh, Computer Science Ph.D. student; and Kirill Mechitov, Computer Science Ph.D. student.
For more information on the Illinois Structural Health Monitoring Project and the Structural Health Monitoring Services Toolsuite software, visit http://shm.cs.uiuc.edu/.
Story by the Illinois Structural Health Monitoring Project, Jennifer La Montagne and Celeste Bragorgos
Photos, top to bottom:
The Jindo Bridge in South Korea, which connects the mainland to Jindo Island.
Professor Bill Spencer
Professor Gul Agha
At work during the deployment, left to right: Professor Chung-bang Yun of KAIST; Professor Gul Agha from Illinois' Department of Computer Science; Illinois CEE Ph.D. student Shinae Jang; and Illinois Computer Science Ph.D. student Kirill Mechitov.
One of the boxes containing the wireless sensors, affixed to the bridge with strong magnets.