The SPECTRE d-GMM (Ground Movement Monitor) integrates a rugged magneto-strictive displacement sensor for geotechnical monitoring of rock deformation. It has an on-board microcontroller running YieldPoint’s proprietary d-Tech signal processing and transmission technology to provide a high precision single point displacement sensor.
The microcontroller provides linearization, temperature compensation and outputs an ASCII encoded RS485 signal digital signal. Output signals can be transmitted over 250m/900ft without distortion. Each instrument is individually calibrated to ensure that the resolution (<0.01mm) and accuracy (0.25% typical) are an order of magnitude better than for similarly priced technology.
The digital form of the signals eliminates the necessity for expensive analog-to-digital conversion and results in low cost monitoring peripherals that output data in real world units (mm and degC). The instrumental is fully compatible with d-Logger, d-Mesh and d-Reader and can be networked using the IoT gateway.