A Study On Key Technology In High Precision Control Of Velocity And Image Stabilization Of Gyro Stabilized Electro-Optical Mechanism

With the transformation of modern warfare and the rapid development of military equipment from mechanization to informatization,the role of passive search and tracking system for covert detection and target tracking is becoming more and more prominent to response to the growing threat of the low,small,slow targets like UAV,armed helicopters and cruise missiles.The research object is electro-optical precision pointing mechanisms which is able to search for target in high velocity and track it,which require higher precision in both searching and tracking.In the paper,to improve the accuracy of the velocity stabilization and the target tracking of the precision pointing mechanisms,the author mainly focuses on the velocity estimation,disturbance rejection and the target tracking of the gyro stabilized electro-optical mechanism.The main work is organized as follws:1.Pointing at the pointing mechanisms which require absolute encoder to measure position,the velocity estimation based on position was studied.The error of velocity estimation was analyzed according to the velocity measurement by position differential.The kalman filter and adaptive kalman filter were applied in velocity estimation based on position with noise.The simulation showed that,compared with other velocity estimation methods,the kalman filter was more accurate,and the precision turned out to be higher with the use of adaptive kalman filter.2.Focused on the high precision velocity control of the precision pointing mechanisms,the control precision was compared between the nonlinear PID controller and the regular PID controller,and the simulation results were provided.A disturbance observer based on the extended state equation was adopted to observe and compensate the periodic disturbances in the velocity control.The simulation results showed that the disturbance observer performed well in observing low-frequency periodic disturbances,and the observation error increased obviously with the increasing of disturbance frequency.3.Aiming at the design of the gyro stabilization loop,the zero drift characteristic of the selected optical fiber gyro was tested.The low-pass filter and the extended disturbance observer were used to suppress noise in gyro signal external disturbance in order to improve the image stabilization accuracy of the pointing mechanisms on the moving base.It was pointed out that the noise and lag of the target miss distance were the main reasons of the lag error of the target tracking.A target prediction tracking filter based on ? - ? - ? - ? filtering was designed to predict and correct miss distance,which was shown to be obviously effective in predicting the position of the moving target according to the simulation results.4.Based on the ?C/OS-II real-time kernel,the main task of the electro-optical mechanism were analyzed and planned.The task trigger and the communication mode between tasks were determined while the specific structure of the control software was designed.The program implementation of control algorithm studied above was briefly explained.5.The hardware configurations and the work mode of a certain gyro stabilized electro-optical mechanism were illustrated.The velocity control and the image stabilization control were used and tested,and the experiment results showed the validity of the research work.