Research On In-missile Calibration Technology Of Medium And Low Precision FOG-IMU

As time going,the inertia sensors,such as fiber optic gyroscope(FOG)and quartz flexible accelerometer,had been changed by photoelectron devices ageing and structure deformation,which used in the inertial measure unit with fiber optic gyroscope(FOG-INS)installed in missile.It was serious to the guidance accuracy of missiles.The conventional practice was taking the FOG-INS out of the projectile body and scheduled calibration.The human resource and servicing cast would be increased.Meanwhile the war preparedness duty of the tactics weapon would be influenced.Aim at the complexity and workload of the dismantle missile,the art put forward an in-missile calibration scheme with the medium and low precision FOG-INS.The paper contents and contributions include the flowing respects:1.The error analysis of the in-missile calibration with the FOG-INS was derived,which depended on the fundamental of the strapdown inertial navigation system(SINS).The study discussed the regular disseminate of the inertial sensors in the in-missile calibration system and simplified the mathematical model.Combined by the SINS fundamental,the work provide a mechanical model and inferred observation equations of the FOG-INS.2.Beginning with the discrete calibration technique,the work put forward parameter estimation equations.The influence of the test equipment deviation and environment variable to the calibration was analyzed.According to the theory of the in-missile calibration,the work dissected lever arm and established all error parameter filtration model.3.Aim at the problem of the ADOP observability analysis,the study took out a new way to content the unbiasedness by rebuilding system equation and measuration equation.The work provided several calibration plans depended on the characteristic and limit of the miniature missile.The project had been observability analyzed by ADOP technique.Meanwhile,the practicability of the calibration scheme design with ADOP method had been proved by the mathematical simulation,and the calibration procedure had been adopted.4.The work experimented several in-missile calibration semi-physical tests by using the high accuracy FOG-INS as the reference.Contrasting the result of the discrete experiment with the in-missile calibration,the precisions of the two means were similar and the test time of the later was shorter than the former.The repetitiveness of the in-missile calibration had been proved by the result.Then the static and vehicle navigation experiments were carried out with the FOG-IMU compensated by the two calibration results.The conclusion indicated that the navigation accuracy were resemble between the two compensations.Further,the practicability of the in-missile calibration was testified.This paper had been shown that the application of in-missile calibration cut away the high precision equipment and strict trial environment.Contrasting with the convention method,the experiment time had been pared and the precision had the same grade.The effective and feasibility of the in-missile calibration was proved by theory derivation and experiment verified.Research in this paper provides theoretical basis or technical references for the design of the subsequent engineering products.