AZIMUTH MEASUREMENT DEVICE

摘要

An azimuth measuring device which can obtain offset information corresponding to one in the case where the direction of the azimuth measuring device is arbitrarily changed, without obtaining erroneous offset information when changing the direction of the azimuth measuring device while retaining its attitude with respect to a specific direction, is provided. A data processing section 19 processes data from a triaxial sensor which detects earth magnetism. In the data processing section 19, triaxial output data at the time when the direction of earth magnetism changes in a three dimensional space are repeatedly obtained not smaller than a predetermined number of times; the coordinates of a point where the variation of distances from a group of triaxial output data is minimum in a three dimensional coordinate which triaxial output data are related to respective axial components is estimated by using a statistical method, and is set as a reference point; offset information is calculated based on the coordinates of the reference point, and it is determined whether the group of triaxial output data is distributed in the vicinity of a specific plane; and when it has been determined that the group of triaxial output data is distributed in the vicinity of the specific plane, the coordinates of a reference point are not estimated, or the coordinates of an estimated reference point is deleted.