Structural Health Monitoring (SHM) based on the Hi-Performance WestNode

The WestNode is a high-performance device for real-time structural health monitoring of private and public buildings and infrastructures, such as bridges, towers, pillars, etc. Accurate and continuous monitoring of the structures’ vibrations helps programming prompt intervention to avoid or limit structural risks and their direct or indirect consequences for people and goods.

This board evolved from a previous device developed in collaboration with the University of L’Aquila; the previous experience has led to notable performance improvement.

The board is based on a low-power microcontroller (MCU) by ST Microelectronics (STM32F4 family). This 32-bit MCU offers several high-performance communication interfaces. The board also includes a slot for microSD cards for local data storage.

A tri-axial MEMS accelerometer is connected to a 24-bit Analog-to-Digital Converter (ADC) mounted on the board. The ADC has eight channels and can simultaneously sample them at a frequency of up to 64 kHz; the board locally elaborates the vibration data to reduce the quantity of data to transmit remotely.

The board fully complies with the typical requirements of SHM applications, which typically require data sampling up to 200 Hz. In addition, the WestNode offers the possibility to acquire signals from external sensors, such as clinometers and crack meters, both often used in the field of SHM, after seismic events that cause severe damage to the structure.

Additional external sensors, such as environmental sensors (temperature, humidity, light, hygrometer), can be attached to the WestNode through direct acquisition of their analog signals on the free channels of the ADC. This last characteristic enables high flexibility of the installations and the use of our WestNode to promote added value monitoring services beyond the seismic analysis scope.

More details are available in our Brochure.

Some installations

Inclination profile of a tower building

Statistical distribution of hourly average acceleration and estimated inclination profile.

A few earthquake events detected by our system in some installations and charts in the time domain.

Analysis in the frequency domain of an earthquake detected.

Animation of the displacement induced by a Mw4.6 earthquake to an 8-floor building equipped with our system (distance from epicenter 96.6 km) and recording of acceleration traces along the three axes on each WestNode.