Research On Some Key Technologies For Single-axis Rotation Inertial Navigation System With Mechanically Dithered Ring Laser Gyroscope

High precision inertial navigation system (INS) plays an important role in military applications. In order to get high precision single-axis rotation INS and attitude &heading measurement system, the auto-compensation techniques, structural and temperature characteristic of the mechanically dithered ring laser gyroscope (MDRLG) have been studied in theoretical and engineering aspects in this dissertation. The high precision single-axis rotation INS and the attitude&heading measurement system are developed. The main work we have done in this dissertation includes:1. Theoretical research and error characteristic analysis on the auto-compensation principle of the single-axis rotation INS. The essence of the auto-compensation for the single-axis rotation is analyzed in frequency domain. The effects of auto-compensation are studied such as inertial element bias error, scale factor error, misalignment error, random walk error and initial error. The influences of the rotation mode, sawtooth velocity error, rotation accuracy, rotation rate are discussed and a suitable rotation scheme is put forward. Error analysis of single-axis rotation INS on moving base is performed and the error distribution scheme is given.2. The structural and temperature characteristic analysis of the MDRLG which is the core component in the single-axis rotation INS. The static and dynamics analysis of the MDRLG are processed by theoretical research, finite element analysis and experiments. A new dither mechanism against vibration environment is put forward. In the case of guarantee of the installation precision, optimization design of the mounting case is done which can provide reference to reduce weight for INS. The temperature characteristic of the MDRLG is simulated by the finite element method. In order to reflect temperature gradient impact on the MDRLG more comprehensively, the multi-point temperature compensation is need. A multi-point temperature compensation method is design which can improve the temperature compensation effect.3. Multi-position alignment and identification of the axial MDRLG drift. The compass loop and Kalman filter method is used to modify the drift of the MDRLG and accelerometer. Because of the weak observability of the axial MDRLG drift, a RBF neural network which inputs are the latitude error and change of the temperature is put forward. The different neural networks are adopted to identify the axial MDRLG drift for the steady and non-steady state. The results show that the identification precision of the axial MDRLG drift is less than 0.0003o/h.4. The non-damping scheme with the MDRLG is studied exploringly for accuracy attitude and the attitude&heading measurement system is developed. The traits of the structure and heat for the attitude&heading measurement system are introduced. The performance of the attitude&heading measurement system is tested including static experiments, wobble experiments and long time navigation experiments. The attitude measuring accuracy in 24 hours achieved 25 '' and the heading attitude measuring accuracy achieved 30''. The attitude measuring accuracy in 7 days achieved 30''and the heading attitude measuring accuracy achieved 1''.5. The single-axis rotation INS is developed and plenty of work for single-axis rotation INS is done, including: design of the framework, selection and test of the main elements, instruction of software and hardware, analysis of magnetic shield. The performance of the single-axis rotation INS has been tested comprehensively, including static experiments, dynamic experiments, Dong-ting lake experiments, mooring and sailing experiments, which show the maximum position error is less than 1 nautical mile in 72 hours, 2 nautical miles in 120 hours and 4 nautical miles in 240 hours.