Key Technology Of Dual Spindle Rotating Inertial Navigation System

.High precision of the inertial navigation needs not only high precision inertial measurement element(accelerometer and gyroscope),but also they need excellent error compensation and suppression technology. And on-line calibration technology and rotating modulation technology is to realize the error compensation and the concrete methods of suppression. Error parameters can be determined and compensation by online calibration.Improve the ships navigation accuracy and battery life. Rotating modulation technology is suppress spread over time the navigation error made and turn it into the form of periodic oscillation and hold the divergence. Due to the limitation of installation technology and precision still can cause other error in the process of rotating modulation. The problems need to be solved. The main content of this article:First of all, modeling of inertial components and clearing the relationship between the navigation error and components. Clear the relationship between the each coordinate system and its transformation with a turntable. Comprehensive analysis of commonly used calibration method is put forward a kind of suitable for laboratory system-level calibration method of fiber optic gyroscope. A set of dual spindle 12 position rotation scheme was put forward. Introduces in detail the scheme principle and calibration step. Explain why some parameters can't be measured for the low degree of observable. The last part formula is derived so that each error will be derived from the different navigation error equations.The second, from the analysis on principle of the dual spindle rotating modulation technique. Dual spindle inertial navigation system prototype is showed by the schematic diagram. Make a intuitive impress about dual spindle inertial navigation system prototype.Theoretical analysis of the navigation error is caused by misalignment between what are three turntable shaft axis, IMU axis, carrier shaft. And different navigation errors caused by rotation axis was deduced. Then the saw-tooth wave speed error caused by the dual spindle rotating modulation process are analyzed in theory and put forward the corresponding improvement method. The turntable angle measuring mechanism Inaccurate cause impact for attitude modulation. Conclusion inner shaft Angle measuring inaccurate will bring both three attitude Angle error while the outer axis affects only the roll Angle.In the end, based on the above theoretical derivation and analysis of simulation and physical experiment verification. Including the dual spindle calibration scheme simulation is put forward. In the calibration before and after calibration compared the navigation simulation image. Verified the correctness of the theory in finally.Calibration experiments were performed that made a analysis to experimental and theoretical results of different. Then carries on the simulation of biaxial rotating modulation technology. Respectively, compared the static and modulation on navigation error .Proved that the rotating modulation theory play a role in suppress navigation error. The reason why song-hua river navigation experiment is not better than laboratory experiments is analyzed.Attitude demodulation experiment was carried out that pictures show the rollers by dual spindle position error of the effects of posture demodulation .and intuitive to show the serious impact on the navigation error. Proves the necessity of the work. Indicate the focus of the work in future.