Research On Strapdown Gyrocompass System

Gyrocompass system is a kind of navigation equipment, commonly used on aircraft carriers,ships and so on. Gyrocompass system was divided into two categories,platform compass system and strapdown compass system. Since the electromechanical gyroscope was the mainly composed of the device in gyrocompass system, the maintenance costs of gyrocompass were relatively high. And the poor reliability and start time of the system was relatively long. As one after another of the optical gyro, strapdown compass system will get a sustainable development, but also with the advantage of high dynamic accuracy, the short settling time, self-aligning and so on. This paper first studied the self-aligned technology of strapdown compass system in mooring environment and initial alignmen algorithm in moving base environment as well as their discrete algorithm,then analyzed and designed compass state and made strapdown gyrocompass system adapt to different sea conditions through the use of damping solution in inertial navigation system.(1) As a navigation device to provide attitude information for the carrier, attitude updating algorithm was an important component in strapdown gyrocompass system. This article first studied attitude updating algorithms commonly used in strapdown gyrocompass system in detail, mainly discussed and analyed quaternion and rotation vector method often used in the attitude update algorithm and then made simulation research for the two attitude updating algorithms.(2) Since the compass circuit was the core of strapdown compass system,this paper carried out a detailed analysis of the circuit when the carrier in the mooring environment and made simulation analysis at the stationary base and swing environment simulation environment, respectively. And this paper made off-line simulation through the acquisition gyro data. Simultaneously, because the carrier's maneuvering and the environment affect will have an effect on the alignment process. Then on the basis of analysis the impact on the alignment process in the motion vector,proposed the alignment algorithm base on the outer velocity-assisted in the moving base. Finally, simulation result showed the effectiveness and correctness of the method.(3) Strapdown gyrocompass system mainly works in the compass state. Based on the analysis of compass loop and carrier maneuvering, this paper gave the design principles of parameters in the compass state and simulation under different mobility environments and made off-line simulation through the acquisition gyro data. In addition, in order to make strapdown gyrocompass system adapt to more complex sea condition and maneuvering, this paper researched and analyzed the state switching technology of the strapdown gyrocompass system to compensate for errors which bring the state compass due to carrier maneuvering.(4) Since the damping solution of inertial navigation system can adapt to different motor vehicle movement and suppress the navigation error effectively. So this paper researched navigation error suppression in strapdown compass system by using INS damping solution.First, made a brief introduction to the design configuration of full damping network. Then,according to the characteristics of the navigation system, this paper gave the damping network design principles, analyzed ? = 0.5 of second-level damping network and then mainly to the presence of the orientation of the Earth's periodic oscillations designed third-level azimuth damping network which? is 0.1?0.2? 0.3 and 0.4 of. It made the system a good adaptability when the carrier motorized sailing.This paper conducted in-depth study on algorithms and compass status and other critical issues in strapdown gyrocompass system. The simulation and off-line simulation through the acquisition gyro data results showed the effectiveness and implementation of the proposed method and hope this paper can have some reference for strapdown gyrocompass system research.