System for Acquisition, Processing, and Storage of Clinometric Data Using Advantech and Node-RED

Abstract

This report describes the design and field deployment of a data acquisition and transmission unit for the borehole tiltmeter network of the Istituto Nazionale di Geofisica e Vulcanologia (Osservatorio Etneo, Catania). The unit upgrades the geodetic stations so that ground deformation on the active Sicilian volcanoes can be followed in near real time. It is built around an Advantech SmartFlex SR303 industrial router, connected over a serial-to-IP link to deep borehole self-leveling tiltmeters. All processing and file formatting are handled by event-based flows running in a Node-RED environment on the router itself. The unit parses the 1 Hz data stream, computes local averages over 1-minute and 15-minute intervals, and stores them in non-volatile local memory managed as a circular ring buffer. A software hysteresis routine watches the battery voltage: below 11.5 V it shuts down the 4G/LTE link to save power, while local geophysical logging keeps running. An onboard satellite (GNSS) receiver keeps the clock accurate to the microsecond even when the telemetry link is down. The Catania centre retrieves the stored files through scheduled automatic downloads.