Reliable vibration data for structures that must not fail
Structural health monitoring (SHM) uses continuous vibration measurement to assess the condition and dynamic behaviour of bridges, buildings, dams and heritage structures over time. Accurate data helps engineers detect changes, identify anomalies and plan inspection and maintenance.
AMCORIS supplies Epson quartz MEMS (QMEMS) accelerometers and vibration sensors and supports you from sensor selection to integration.
QUICK ANSWER
Which accelerometer is right for SHM?
The sensor's self-noise decides whether weak ambient vibrations and higher structural modes can be identified. An independent study by Italy's National Institute of Geophysics and Volcanology (INGV) with Epson recommends a self-noise below 1 µg/√Hz for SHM and below 0.5 µg/√Hz for reliable operational modal analysis (OMA). The Epson M-A370 measured 0.02 µg/√Hz in the 1–10 Hz band; the M-A352 is specified at 0.2 µg/√Hz.
WHY SELF-NOISE MATTERS
Below the noise floor, structural modes disappear
Structures under ambient excitation move in the micro-g range. If the sensor's own noise is higher than the structural response, modes vanish in the noise floor and changes over time cannot be detected reliably. Epson's QMEMS sensors convert acceleration into the frequency change of a quartz resonator and reach noise levels previously reserved for force-balance accelerometers. In the INGV study, conventional capacitive MEMS accelerometers showed clearly higher self-noise than the Epson M-A370.
Self-noise in µg/√Hz, log scale. Shorter is better. Dashed lines: INGV targets.
Epson M-A370
Epson M-A352
Sources: Patanè et al., Sensors 2026, 26, 5528, doi.org/10.3390/s26175528 (open access, CC BY); Epson M-A352 specification.
INDEPENDENTLY VALIDATED
Proven on castles, bridges and seismic networks
INGV, Seiko Epson and Epson Europe Electronics evaluated Epson QMEMS accelerometers in the lab and in long-term field use. According to the authors, the M-A370 delivers data quality comparable to engineering-grade force-balance accelerometers.
United Kingdom · M-A370
Durham Castle clock tower
Ambient vibration testing of a heritage structure.
United Kingdom · M-A370
Cable-stayed pedestrian bridge
Operational modal analysis of a steel footbridge.
Ragusa, Italy · M-A352
Papa Giovanni XXIII arch bridge
Long-term SHM of a reinforced-concrete arch bridge.
Campi Flegrei, Italy · M-A370
Residential buildings
Structural monitoring in a volcanic area.
Italy · M-A352
Urban Seismic Observatories
Catania, Campi Flegrei, Messina–Reggio Calabria, Potenza and others; 50+ units in Campi Flegrei alone.
These projects were carried out by INGV and Epson. AMCORIS supplies the same sensors and supports their integration.
Read the study →SENSOR SELECTION
Which Epson sensor for which SHM task
All sensors measure three axes with a digital interface. Choose by noise level, interface and installation environment.
M-A352AD10Available online
UART/SPI · 0.2 µg/√Hz
Bridges, buildings and dense seismic networks.
Buy now →M-A370AD10On request
UART/SPI · 0.02 µg/√Hz
Ultra-low-noise OMA, heritage structures, quiet sites.
Product details →M-A542VR10On request
RS-422 · vibration sensor
Drives, gates and machinery on the structure.
Product details →M-A342VD10On request
UART/SPI · vibration sensor
Compact monitoring of machinery and equipment.
Product details →FROM AMCORIS PROJECTS
Integration examples
Epson sensors integrated into real-world monitoring of bridge and floodgate infrastructure, where reliable long-term vibration measurement is essential.
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Challenge
Bridge Vibration Monitoring
Continuously assessing the dynamic behaviour of a bridge to identify changes in structural response over time.
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Solution
Bridge Vibration Monitoring
An Epson MEMS vibration sensor was integrated into a dedicated monitoring unit to capture structural vibration data for long-term analysis.
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Result
Bridge Vibration Monitoring
The system provides reliable vibration data that supports structural assessment and long-term monitoring of the bridge.
M-A352AD10
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Challenge
Floodgate Drive Monitoring
Monitoring the motors that open and close the gates of a lock and floodgate installation, where unplanned downtime affects critical water infrastructure.
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Solution
Floodgate Drive Monitoring
An Epson M-A542VR10 vibration sensor with RS-422 interface was mounted on the gate drive motors to continuously capture three-axis vibration data.
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Result
Floodgate Drive Monitoring
Early detection of wear on the gate drives supports condition-based maintenance and reliable operation of critical water infrastructure.
M-A542VR10
More Epson Accelerometer & Vibration Sensors
Why engineers choose AMCORIS
Monitoring expertise
Real-world experience with bridges, dams and critical infrastructure.
Validated QMEMS sensing
Self-noise down to 0.02 µg/√Hz, evaluated in the field.
Application engineering
Sensor selection, evaluation kits and integration support.
Long-term reliability
Robust sensors for continuous outdoor operation.
Frequently asked questions
What self-noise does an accelerometer need for structural health monitoring?
The INGV study recommends below 1 µg/√Hz for general SHM, below 0.5 µg/√Hz for reliable operational modal analysis and close to 0.1 µg/√Hz or lower for very quiet sites.
Can MEMS accelerometers replace force-balance sensors in SHM?
For many applications, yes: in the INGV study, the Epson M-A370 reached 0.02 µg/√Hz and delivered data quality comparable to engineering-grade force-balance accelerometers, at lower size and power consumption.
What is operational modal analysis (OMA)?
OMA identifies natural frequencies, damping and mode shapes of a structure from ambient vibration, without artificial excitation. Low sensor self-noise is essential to resolve weak and higher modes.
Can I test the sensors before ordering?
Yes. Request an Epson evaluation kit from AMCORIS and test the sensor in your own setup. The M-A352AD10 can also be ordered directly in our online shop.
