Cause: caused by vertical damping method.
Elimination method:
(1) External compensation method — calculate the magnitude and symbol of latitude error according to the latitude error formula, and deduct it from the reading of gyro compass;
(2) Internal compensation method — calculate and output the signal that transforms according to the law of latitude error, and apply the compensating moment to the gyro compass.
Velocity error
Causes: the movement of the base changes the implicated movement of the main axis of the gyro compass, resulting in pointing error.
Elimination method:
(1) Speed error correction table;
(2) external compensation method — using mechanical simulation method to calculate the error value according to the expression of the velocity error and deduct it from the heading reading;
(3) Internal compensation method — calculate and output regular speed error compensation torque to implement compensation for gyro compass.