“Bridges and buildings need to be checked over time to identify weaknesses or abnormalities. While the existing inspection method is similar to an annual health checkup, our structural health monitoring is a technology that continuously observes the condition of structures, like a smartwatch. By using sensors to constantly observe how much a structure shakes and moves, we can detect small abnormalities early and prevent major accidents.”
Sohn Hoon, professor of civil and environmental engineering on the Korea Advanced Institute of Science and Technology (KAIST) and recipient of the June Korea Science and Technology Award, made these remarks Tuesday about his high-precision displacement sensor expertise. The award is hosted by the Ministry of Science and ICT (MSIT) and co-organized by the National Research Foundation of Korea and Seoul Economic Daily.
More than 98 p.c of amenities worldwide are small and medium-sized buildings, the place displacement happens on the millimeter stage, making exact commentary important. Displacement refers to the change in distance and route an object strikes from its preliminary place to its last place. It is a measure of how minutely a bridge or constructing has moved from its unique place due to exterior impacts. However, present high-priced tools prices greater than 40 million received per unit, limiting area deployment. This has left quite a few small buildings unattended in security blind spots.
The sensor developed by Professor Sohn dramatically lowers the associated fee burden to below 1 million received per unit, one-fortieth of the prevailing value. It additionally achieves world-class precision with a median displacement error of 0.026㎜. “Existing GPS-based measurement technology had high equipment costs and measurement accuracy of only about 10㎜, limiting its ability to precisely measure small movements in small and medium-sized structures,” Sohn stated. “The sensor we developed reduces power consumption and includes wireless communication functions, allowing structures to be monitored continuously over long periods.”
The key to commercializing the brand new expertise lies in combining two sensors of various traits to offset their weaknesses. The sensor applies an unique expertise that fuses millimeter-wave radar with a low-cost MEMS accelerometer. “Radar can easily measure the displacement of slowly moving structures but can miss rapid vibrations,” Sohn defined. “On the other hand, the accelerometer captures rapid vibrations well but cannot accurately capture slowly accumulating movements that occur over time.” He added, “By analyzing inexpensive accelerometers and radar together, we can effectively reduce errors and achieve highly precise displacement measurements.”
Professor Sohn’s analysis workforce put in the sensor on Sejong’s Yi Eung Bridge for about three years to confirm its long-term efficiency and applicability in precise area situations. The workforce additionally utilized it to abroad websites, together with a freeway in San Jose, U.S., a parking constructing at Stanford University, and a bridge in Weifang, China. Through greater than 13 area demonstrations at house and overseas, the sensor has confirmed its world-class reliability. “The developed sensor has been verified in actual field conditions through cooperation with research institutions in various countries, including the United States, China, and France,” Sohn stated. “In particular, we are expanding field applications and commercialization possibilities in the U.S. through the National Research Foundation of Korea’s Global Basic Research Laboratory program and the Ministry of Land, Infrastructure and Transport’s international cooperation R&D project.”
The expertise is predicted to increase to areas beforehand troublesome to handle with present sensors, together with structural well being monitoring of small and medium-sized buildings, monitoring throughout development, precision development, and load-bearing capability testing. “To apply the sensor widely to small and medium-sized structures, not only equipment prices but also installation and maintenance costs had to be lowered,” Sohn stated. “To this end, we designed the sensor to transmit data wirelessly and operate without separate measurement equipment, enhancing installation convenience.”
The workforce additionally targeted on constructing a sensor system able to long-term operation. “We embedded decision-making functions inside the sensor so that, rather than sending all data collected in the field, only the necessary results are transmitted,” Sohn stated. “This allows managers to easily oversee many structures.” He added, “We sought to implement a field-oriented system capable of long-term operation by reducing the power supply burden through battery use and solar panel integration.”
The analysis final result is a case by which unique expertise developed by MSIT’s Basic Research Program — the Leader Researcher and Basic Research Laboratory (BRL) initiatives — led to precise commercialization and expertise switch. The findings have been revealed within the worldwide journal Mechanical Systems and Signal Processing in January 2023.
Professor Sohn is an authority on civil engineering and structural security diagnostics who was named KAIST’s youngest tenured professor in his early 40s. For the previous two years, he has concurrently served as director of the Korea National Railway’s Railway Innovation Research Institute, working to apply superior applied sciences to the nationwide facility security administration system. He just lately took on the function of director of the Railway Infrastructure Innovation AX Research Group, main the development of nationwide good infrastructure. “The sensor technology is significant in that it has laid the technological foundation for the precise management of small and medium-sized facilities that had been excluded from continuous monitoring,” Sohn stated. “Going forward, I will continue AI-based digital twin research to lead a paradigm shift in the safety diagnosis market through automation, unmanned operation, and intelligence, contributing to public safety and disaster prevention.”