Research On Comprehensive Calibration For Single-axial Rotation Strapdown Inertial Navigation System

Single-axis rotation Strapdown Inertial Navigation System(SINS)has more precise navigation information than traditional Inertial Navigation System(INS),and could meet the needs of navigation for ship.From the history and direction of INS to view,Single-axis rotation SINS is also promising.Single-axis rotation SINS could compensate the inertial element error on the plane perpendicular to the axial and improve navigation accuracy,but could not compensate the axial inertial element error especially gyro drift,and the longitude error would still accumulate.Using comprehensive calibration techniques to estimate gyro drift by filter could meet the needs of navigation accuracy for long time.However,the process of filtering is affected by many factors,so it is necessary to design a filtering scheme to analyze and solve these factors.Characteristics such as nonlinear,random and non-stationary make it difficult to predict gyro drift,so the mult-scale wavelet kernel Support Vector Machine(SVM)was designed to solve this difficulty.SVM has a good ability to handle nonlinear problem and wavelet analysis can handle signal with multi-scale and multi-resolution.The mult-scale wavelet kernel SVM combine the advantages of SVM and wavelet analysis,thus the designed algorithm could predict the gyro drift sequence accurately,and improve compensation effect.Based on the single-axis rotation SINS error models,the influence of inertial element on navigation error is summarized and evidences for future research are provided.To eliminate the schuler oscillation influence on long-endurance,the level damping network is designed,and it is verified by simulation.Analyses on the theory of federated Kalman filter,GPS and DVL,the single-axis rotation SINS/GPS/DVL integrated navigation error models are proposed based on federated Kalman filter,and the establishment of the models are derived and described in detail.By means of observability analysis,the design scheme is verified by the feasibility of axial gyro drift estimated.The design is also tested by estimation of gyro drift on motion base and stationary base and comprehensive calibration,the simulation results can be used as the improvement of the design and follow-up work of reference.In view of the process of estimation of the axial gyro drift on integrated filter,the four factors affecting the precision of the gyro drift are studied.According with the problems that the process noise statistic properties are uncertain,the Kalman filter models based on support vector machine is put forward and achieved.The influence of ship maneuvering such as acceleration motion on estimation of gyro drift is studied by simulation,the laws of the influence of acceleration motion on estimation of gyro drift are given.When the GPS signal is missing,the subsystem of SINS/DVL still estimates the gyro drift based on the fault tolerance of federal filter.The relationship between filter time and estimation precision of the axial gyro drift,and the influence on comprehensive calibration are studied by simulation,a general conclusion of them is drawed.