Study and Application of Variable Period Sampling in Strap-down North Seeking System

In order to shorten the north-seeking time on the basis of ensuring the north-seeking precision, according to working principle and project practice of strap-down north-seeking system, a kind of variable period sampling method is designed based on the traditional stationary sampling period. This method sets the different sampling period on a basis of the sampling difference of dynamically tuned gyro in each measurement position. While ensuring the north-seeking precision in every measurement position, reduce the north-seeking time by shortening the sampling period; avoid the conflict of north-seeking time and north-seeking precision in the stationary period sampling. The experiment results show, this method efficaciously enhances the north-seeking efficiency, which is to reduce the north-seeking time from 4.5 min to 3.5 min on the base of ensuring the north-seeking precision(less than 30″).