A low-cost innovative wire distance meter for landslide early warning

Abstract

<p>Nowadays the monitoring of slope evolution is still a relevant challenge in the field of engineering geology especially for expensive costs of the ordinary monitoring instruments. However, providing suitable alert levels is essential to ensure the safety of the infrastructures affected by landslides and to mitigate and manage the risk associated.</p> <p>In this context, we developed a low-cost (~ 150 €) Arduino© based wire distance meter (A-WD) capable of measuring the distance between two fixed points with a resolution of less than 1 mm. Our innovative prototype exploits a rotary encoder able to measure infinite displacements and works in both extension and compression conditions, differently from the traditional ones equipped with potentiometric sensors.</p> <p>The device is equipped with a data logger and an online data transmission system.  Although the data  are collected continously, the sending temporal frequency is 5 minutes. The communication module provides alerting by means of SMS when the displacement exceeds the user defined threshold value.</p> <p>The A-WD is being tested on a local earth-flow in South Italy with aim to evaluate the accuracy and reliability of the system through multi-temporal GNSS surveys comparison. Although the prototype is at an experimental stage, our preliminary results suggest that this system could be used as a cost effective early warning system.</p>