Design of Underground Displacement Measurement System Based on Mutual Inductance and Hall Effect

Abstract

Abstract Deep displacement monitoring of rock and soil is important for landslide warning. By using mutual inductance effect and Hall Effect, the author designed the underground displacement sensing unit through the solenoid and permanent magnet and the Hall sensor. The author designed the Hall voltage measurement circuit and installation device, and used the mutual inductance voltage measurement circuit that the laboratory has realized, which can accurately collect the mutual inductance voltage and the Hall voltage in real time. Through the 485 communication, the collected data is transmitted to the upper computer, the mathematical model established by the curve fitting method can be used to measure the real-time displacement of the deep part of the rock and soil. The experimental result shows that the horizontal displacement measurement range is 0-40mm, and the measurement accuracy can reach 1.5mm. It can measure the underground displacement within a reasonable error range.