| 摘要 |
PROBLEM TO BE SOLVED: To solve a problem, in a direction sensor for calculating an offset of a magnetic sensor from an output of a magnetic sensor, wherein the offset is not accurately found and resultantly accurate direction is not calculable. SOLUTION: This direction sensor comprises: a magnetic sensor 1 for detecting earth magnetism to output an output of the magnetic sensor; an offset calculation means 3 for calculating a primary offset based on the sensor output in four different attitudes; an offset processing means 4 comprising a reliability evaluation means for determining whether or not the output is within a preset range when the sensor is in a posture different from a attitude used for calculating the primary offset on the basis of the primary offset calculated by the offset calculation means and discarding the primary offset when the output is determined to be outside the preset range while outputting a secondary offset effective in offset calibration; and a direction calculation means 5 for performing offset correction on the output after acquiring the secondary offset and then calculating a direction. COPYRIGHT: (C)2007,JPO&INPIT
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