Patent ID: 7162807
Filing Date: 2007-01-16
Classification: G01C

Abstract:
1. A geomagnetic sensor, comprising: a main body; a rotation angle measurement part that measures pitch and roll angles of the main body with respect to the surface of the Earth; a geomagnetic measurement module that outputs an electric signal corresponding to the geomagnetic field; a memory that stores predetermined reference azimuths and output values of the geomagnetic measurement module corresponding to changes of the pitch and roll angles; and a controller that calculates azimuths by use of the output values of the geomagnetic measurement module, the pitch and roll angles, and predetermined dip angles, wherein the controller establishes at least two dip angles, calculates the azimuth for each dip angle, compares the azimuth to the reference azimuth, and determines a dip angle at the azimuth having a smaller azimuth error as a current dip angle.