Study On Technology Of Orientation And North-Finding Based On Fiber Optic Gyroscope

Inertial north-finding is important part of inertial technology field, is one of the important safeguard technologies to ensure weapon system beat the target quickly, mobile, and precisely in modernize war. North-finder is perfect orientation equipment for position launching in stratagem, tactic and battle, which can provide azimuth benchmark for missile, radar, canon, fish torpedo, airplane, naval vessel and vehicle. The fiber optic gyroscope (FOG) based on Sagnac effect is a new type of all solid state rotation rate sensor that detects angular changes or angular rates relative to inertial space. It has many fine characteristics compared with the traditional mechanical electronic gyro, such as low cost, light weight, long life, high reliability, wide dynamic range, etc. Under the need of missile photoelectric aiming facility, manufacture a set of north-finding and aiming integral system based the single axis FOG made in Beijing university of aeronautics and astronautics in this thesis, to solve the close quarters aiming of missile launching, to measure the azimuth reference. The principle of gyro-north-finder and the develop history of gyro-theodolite is analyzed synthetically. Introduce the all kinds of north-finding system and correlative technologies in the domestic and overseas. The develop of FOG and application in army-civilian field is discuss. Allan standard deviation is used to analyze the random drift of FOG, and establish the random error mode of FOG. Based on practical project, the principle of FOG north-finding system and the technology of related to system construction is discussed and studied in this paper. The influence of platform tilt on the precision of north-finding is analyzed; an accelerator is used to compensate deviation caused by the base tilt. The two-position method, four-method, multi-positions, and successive rotation method are used; experiment data is checked up exceptional value and eliminate it, the north-finding precision is 6.9822′received by the least square method. The FOG north-finder and laser collimation theodolite are assembled to achieve orientation and aiming integral. The aiming precision affected by eccentricity of the encoders that of laser collimation theodolite and the FOG north-finder is analyzed. It lays foundation for switching to project in the future.