STRAPDOWN GYRO DRIFT CALCULATOR

摘要

Drift components in the output of a gyro in a strapdown inertial navigation system are measured by modulating the speed of the gyro wheel in a sinusoidal manner. True angular motion components acting on the gyro are modulated in proportion to the modulation of the wheel speed, while drift components which act on the gyro and which are independent of true motion and wheel momentum are not modulated. By the use of a drift calculator or selected band-pass filters responsive to the modulated output from the gyro, the drift component and true angular motion component may be separated, and the navigation system may be compensated for drift. A unique linear-parabolic modulator produces a digital output equivalent to a sinusoid which may be used to modulate the gyro wheel speed in the appropriate manner.