Research On System Error Analysis And Correction Method Of Photoelectric Theodolite

Ballistic measurement accuracy is the core issue of external ballistic estimation,and accurate ex post data is an important basis for evaluating and analyzing the measured target.Especially in recent years,the long-range precision strike and high-efficiency damage of weapon systems have put forward more stringent requirements for the accuracy of external ballistic testing;the requirements for the target acquisition,tracking ability and post-processing of the optical measurement system have also increased.This thesis is a summary of the research content in the project Software Development of Photoelectric Theodolite Data Comprehensive Processing that the author participated in.Aiming at the systematic error in the test of photoelectric theodolite,the theodolite structure and its measurement principle are analyzed,the measurement error cancellation algorithm is designed,and the software program is compiled to reduce the influence of different errors on the theodolite optical measurement data.The thesis systematically analyzes the measurement principle and error causes of the photoelectric theodolite,and based on this,the simulation research and program realization of the correction algorithm are carried out for various errors that affect the accuracy of the theodolite measurement data.The practical application shows that the expected effect is achieved.The main contributions of the thesis are as follows:1)The various errors generated by the photoelectric theodolite are systematically analyzed,modeled and corrected.By analyzing the relationship between the three axes of the theodolite,the cause of the error is analyzed,the systematic error model of the photometric data is established,and the specific correction method is given.With reference to GJB2234 A,the error parameters are obtained by using the data of the front and rear mirrors,and the error correction is carried out in combination with the parameter model,and the correction effect is verified by the simulation data.2)For the photoelectric theodolite without ranging function,an atmospheric refraction correction algorithm is proposed,which is the successive approximation method combined with layered meteorology（SAMCA）.In this method,with the geocentric angle between the theodolite site and the target remains unchanged,it is divided into a plurality of small enough angles.The change of height corresponding to each small angle is calculated,and finally obtained the true height of the target through integration.This method adopts the "geocentric angle" which is closer to the reality as the integral boundary,which effectively avoids the error introduced by the "pseudo apparent distance",so the accuracy is higher.3)According to the ballistic characteristics of long-range ammunition,the segmentation fitting method is used to improve the ballistic processing accuracy.Different from the existing uniform segmentation method,this paper divides the full trajectory into active segment,passive segment and guidance segment through the force change of the projectile during flight.The Kalman filter is used to obtain the speed and acceleration of the missile during flight for judgment.When the speed reaches the maximum value,the active segment and the passive segment can be segmented.The acceleration of the missile in the passive segment changes relatively smoothly.When it fluctuates significantly,it can be considered that the missile enters the guidance section at this time.Then,piecewise least squares and piecewise cubic spline smoothing are performed to reduce the influence of random errors on the results of the ballistic solution.4)Aiming at the problem of missing true value in outer ballistic evaluation,simulation ballistic data is designed and constructed.When evaluating the performance of the data processing system,it is necessary to have the simulation data containing the true value to effectively evaluate the system error correction results.Therefore,it is proposed to construct the simulation data to further verify the algorithm.All the error correction algorithms in this paper are solidified into the developed photoelectric theodolite data comprehensive processing software.The actual measurement data and simulation data verification show that the algorithm in this paper can meet the accuracy requirements of the post-event data processing outside the shooting range,and the algorithm is stable and efficient.