Substitution calibration method of sky-oriented gyroscope and calibration method of double-gyroscope type navigation equipment

The invention discloses a substitution calibration method of a sky-direction gyroscope and a calibration method of double-gyroscope type navigation equipment. The sky-direction gyroscope and a gratingencoder are respectively arranged at the upper end and the lower end of a transposition table body; the sky-direction gyroscope and the grating encoder are driven to rotate synchronously at a constant angular speed through the transposition table body; the output pulse of the grating encoder is used as a synchronizing signal for collecting the sky-direction gyro output quantity, and one sky-direction gyro output quantity and one grating encoder reading psi'are synchronously collected every n pulses; the measured value psi of the sky-oriented gyroscope is calculated, wherein psi is equal to 2pi theta/theta 2pi, wherein theta represents the output quantity of the sky-direction gyroscope corresponding to the rotation psi angle, and theta 2pi represents the output quantity of the sky-direction gyroscope corresponding