A Designed Calibration Approach for the Measurement-While-Drilling Instrument

The Measurement-While-Drilling (MWD) system, composed of a tri-axial magnetometer and accelerometer, is widely used in the Horizontal Directional Drilling machine coal mines. This system can provide attitude information each measuring point borehole, which will eventually allow trajectory borehole to be drawn. information, however, showed low-level accuracy, due sensor’s imperfection mounting errors. accuracy worsened when low-cost sensors were employed, as they had higher random noise. Therefore, an exploration ways eliminate sensor tolerance well suppress noise needed. In this paper, feasible calibration approach was designed address these issues. new combined three foundational algorithms, including ellipsoidal fitting method, planar inner product invariance method. traditional method optimized by using recursive least square criterion omitting steps sample data acquisition, respectively. addition, suppression involved our improve accuracy. numerical simulation results that number sampling points decreased significantly, but azimuthal angle pitch fully met engineering requirements. experimental error reduced less than 0.5°, azimuth also 2.5°. It should noted could implemented without help other expensive auxiliary equipment.