Method of accurate gyro drift measurement for inertial navigation system

Based on characteristics that orientation reference is needed in measuring gyro drift of stabilized inertial navigation system, an effective method is given to realize self-alignment in addition to gyro´ drift measurement. By using gyrocompass loop, two horizontal axes gyro drift can be measured and compensated. When the system is in state of orientation state, azimuth gyro drift can be approached by least-square. Computer simulation and experimentation results show that this method can measure gyro drift accurately.