Introduction: Continuous Structural Health Monitoring
Between the steel beams of Seoul’s Han River Main Bridge and Busan’s Second Cross-Sea Bridge, assessing “bridge health” once relied solely on monthly manual inspections. Engineers carried total stations, yet lacked data during the critical 48 hours after heavy rain or heavy vehicle traffic.
Today, the Septentrio AsteRx SB3 Pro GNSS receiver—slightly larger than a palm—is installed inside bridge railings, acting as a 24/7 “millimeter-level heart monitor” embedded within the structure.
Field-Proven Millimeter-Level Performance
Weighing 497 grams, the receiver outputs RTK coordinates at 20 Hz and operates reliably from -30°C to +65°C. During 2024 tests, two 40-ton trucks caused a measurable 7.9 mm vertical displacement detected within 50 ms, triggering an immediate 4G alert to engineers.
Under identical conditions, traditional single-frequency GNSS systems exhibited errors up to 30 cm, masking real structural risks.
Key Technologies for Extreme Environments
Full-Constellation Tri-Frequency GNSS
Simultaneous tracking of GPS, GLONASS, Galileo, BeiDou, QZSS, and NavIC ensures more than 30 satellites remain locked even with severe sky obstruction.
20 Hz RTK Deformation Monitoring
A 20 Hz RTK update rate captures instantaneous deformation every 50 ms, sufficient to monitor loads from trains traveling at 80 km/h.
AIM+ Anti-Interference Algorithm
AIM+ actively suppresses electromagnetic interference from radios and vehicle jammers, maintaining centimeter-level accuracy even with 30 dB interference increases.
LOCK+ Shock Resistance & IONO+ Shielding
LOCK+ maintains satellite tracking during vibration and blasting, while IONO+ protects accuracy during ionospheric disturbances.
Deployment Efficiency & Economic Value
With IP68 protection, a 9–36 V power input, and a 10-minute installation time, deployment is reduced by 90% compared to wired systems. Nationwide adoption across 300 bridges could generate over $200 million in annual economic benefits.
Applications extend beyond bridges to mining slopes, subway tunnels, port yards, and high-rise foundation monitoring, delivering real-time millimeter-level deformation data.
Summary:
• Application: Bridge, tunnel, mining, and construction structural health monitoring
• Accuracy: Millimeter-level deformation detection; centimeter-level RTK positioning
• Update Rate: 20 Hz RTK (50 ms refresh)
• GNSS: GPS, GLONASS, Galileo, BeiDou, QZSS, NavIC
• Technologies: AIM+ anti-interference, LOCK+ shock resistance, IONO+ protection
• Reliability: IP68 housing, -30°C to +65°C, 9–36 V wide-voltage power
