Research On High Precision Attitude Measurement And Tracking Algorithm For Shipboard Stability Platform

In tracking and measuring of motion platform,the primary task to realize the stability of the optical axis of the photoelectric tracking system is to isolate the effect of carrier attitude change on the visual axis.However,isolating the motion of carrier acquires the high precisive attitude information of the motion platform.Therefore,attitude acquisition is a prerequisite for isolation of carrier movement.Compared with the traditional methods of optical measurement and star sensor,the laser gyro has the characteristics of high sensitivity,high precision,large dynamic range and not affected by the environment.It is the ideal angular velocity sensor of inertial system.The measurement system based on laser gyroscope can make full use of these excellent features in the attitude measurement process.Starting from the characteristics of laser gyros,the thesis studies the error terms of laser gyro and its causes as well as the methods to reduce the measurement errors.Starting from reducing the most influential sources of errors,the accuracy of the gyroscope's angle measurement is improved.At the same time,the tracking coordinate transformation algorithm of the measured data was deduced,the detailed process of the coordinate transformation was analyzed,and the error produced in the process was analyzed,and the calculation was obtained after coordinate transformation under different pitch and azimuth angles.The resulting new azimuth and pitch angles are compared to the true azimuth and pitch angle error results.The main sources of laser gyro error,including zero bias of laser gyro,scaling factor error,installation error,self-locking,random error,are analyzing,the reasons of these errors and the influence of various errors on gyro angle measurement accuracy are analyzing.Then establishing the error model of the gyroscope.It is found that the zero bias has the greatest influence on the accuracy of the measuring angle.Therefore,to improve the accuracy should start with the elimination of bias.The method of calibration and compensation for error of zero bias and other errors is given in detail.The uniaxial measurement experiment system is designed and constructed,the relevant experiments are carried out,the error analysis and compensation methods are proved to be correct,and experiments are carried out on the vehicle platform to verify the feasibility of the scheme.Through the analysis of the experimental data,the gyroscope measurement accuracy reached 6 "/ h after compensation.Accuracy has reached the expected requirements.