| 摘要 |
PURPOSE:To achieve a highly accurate detection of directions of a moving object continuously by providing a means to switch an earth magnetism sensor over to a rate type direction sensor after directions of the moving object to be detected with the earth magnetism sensor is set as a reference direction of the rate type direction sensor. CONSTITUTION:If it is found that a moving object is still moving straight at a time t2 when a time T set beforehand sufficiently allowed for a delay time in the detection of directions with an earth magnetism sensor body 1 passes after a shift to a straight movement at a time t1 according to the detection of directions with the earth magnetism sensor body 1, an arithmetic control circuit 3 sets a direction of the moving object detected with the earth magnetism sensor body 1 at the time t2 as reference direction in the detection of direction with a rate sensor body 2 and afterward, it leads the rate sensor body 2 to perform a detection of directions cumulatively with the direction set as reference. Thus, at any time after the time t2, the detection of directions with the earth magnetism sensor body 1 can be switched over to that with the rate sensor body 2. |
