When the borehole has an inclination offset of X ′ in the X-axis direction and a Y ′ inclination offset in the Y-axis direction, the diagonal length R of the parallelogram is the horizontal projection offset of the vertex angle of the point R = X ′ 2 + Y′2.
Before putting the instrument into the hole, make a mark on the hole as the starting point of the azimuth. Align the starting mark outside the probe with the hole mark. Assuming that the probe does not rotate in the hole and only tilts, α is the azimuth of the hole. However, in practice, the probe will inevitably rotate arbitrarily after it is placed in the hole. At this time, the rotation angle ω is measured by the gyroscope, and the α of the R side relative to the north direction is calculated by the X and Y sensors, and the azimuth angle Z = α-ω, to obtain the actual azimuth angle Z.
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