A new rapid north-seeking method of pendulous gyroscope

In order to achieve rapid high-precision orientation, a rapid north-seeking method based on 1/2 cycle integral method was presented. Equation of motion and cycle formula of gyro axis with gravity was deduced from North-seeking theory of pendulous gyroscope. Azimuth swinging curve features was analyzed, and the model of 1/2 cycle integral method was established. North was calculated by measuring the time and swing in half of period. It was proved that measurement time is short, accuracy is better than traditional thick north-seeking methods. Accuracy achieves 8″ in 7 minutes combined with refined integral method.