| 摘要 |
<p>The method of the present invention comprises the following steps: revolving an object about an angle of at least 360° during a calibration cycle; calculating the values of horizontal projections of a global vector for the intensity of Earth's magnetic field and the object magnetic field, these values being determined at four points of a magnetic hodograph ellipsis; calculating five magnetic field correction factors from the measured values; calculating during each navigation measurement cycle the averaged values of the projections of the magnetic field vector and that of the gravity-force acceleration on the axis of an instrumental co-ordinate system; defining the horizontal projections of the magnetic field vector; correcting the horizontal projections of the magnetic field; determining the increments in the orthogonal co-ordinates as well as the object co-ordinates; and eventually determining the magnetic azimuth of the movement direction. The device for realising this method comprises the following elements: three magnetic field detectors (1); linear acceleration detectors (2); one displacement detector (3); a calculation unit (4) for determining the horizontal projections of a global vector for the intensity of Earth's magnetic field and the object magnetic field; a calculation unit (5) for determining the correction factors of the magnetic hodograph horizontal ellipsis; a correction unit (6) for correcting the horizontal projections of a global vector for the intensity of Earth's magnetic field and the object magnetic field; a navigation unit (7); a control unit (8); and a conversion and averaging unit (9). This method also uses a compensation accelerometer comprising a sensitive element (21), three amplifiers (22, 23, 24) and two resistors (25, 26). This device also comprises a reference voltage source (27), an electric signal generator (28), a dual transistor (29) having a first type of conductivity, a dual transistor (30) having another type of conductivity, three resistors (31, 32, 33) and two capacitors (34, 35). The accelerometer sensitive element comprises the following members: a mobile plate (41) in the shape of a regular polygon or circle with projections; resilient film-type guys (43); a mounting frame (44); dielectric plates (46); thin-film electrodes (47); and eventually thin-film band-type screens (49) for protecting thin-film electrodes (51).</p> |
