摘要 |
A sensor (10) for measuring angular rate and linear acceleration of a body, in which first and second rotors (30, 31), each carrying a plurality of accelerometers (44, 49), are mounted for counter-rotating dithering motion on opposite sides of a base plate (11). A single permanent magnet (70) is mounted centrally of the base plate, with one pole (71) disposed adjacent the first rotor and the other pole (72) disposed adjacent the second rotor. First and second X-shaped pole pieces (80, 81) are mounted at the respective opposite poles of the magnet, and a plurality of velocity sensing pick-off coils (86) are mounted on the arms (82, 83, 84 and 85) of the pole pieces for cooperation with flux splitting protrusions (34, 35 and 36) on the rotors. The arms of the pole pieces are associated with the flux splitting protrusions so that differential flux splitting is obtained as the rotors are rotated in opposite directions. The accelerometers are arranged in opposed pairs on the respective rotors so that their sensitive axes are parallel to one another but point in opposite directions for canceling common mode error signals, and they are carried on rotor arms (40, 41, 42 and 45, 46 and 47) that converge toward one another from opposite sides of the base plate, so that the accelerometer centers of percussion are spaced closely together and at the same dither radius to minimize cross-axis error signals. A differential torque dither drive for the rotors comprises a plurality of electromagnet coils (19, 20) carried by the base plate for cooperation with armatures (37, 38 and 39) on the rotors to simultaneously rotate the rotors in opposite directions, and a sinusoidally varying energizing current effects opposite or reverse operation.
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