Research On Hull Deformation Measurement Technology Based On Inertial Quantity Matching

The accurate measurement of hull deformation is of great significance for constructing a unified spatial attitude reference and improving the performance of subsystems.The inertial quantity matching measurement method has the advantages of convenient operation,high measurement accuracy and strong anti-interference.Therefore,in this paper,the hull deformation measurement technology based on inertia quantity matching is deeply studied.Aiming at the problem of the time delay and system uncertainty in the measurement process,the corresponding solutions are proposed to improve the accuracy of hull deformation measurement.Firstly,considering the angular velocity information is sensitive to the hull deformation angle,the hull deformation measurement method based on angular velocity matching is studied.The system state equation is established based on the hull deformation angle model and the gyro drift model,taking into account the large installation error angle,a nonlinear measurement equation is established,which together constitute the filter equation and verified by simulation experiments.Secondly,aiming at the time delay problem in real ship measurement,the influence of time delay on the estimation accuracy of hull deformation is analyzed from both theoretical and simulation aspects.Based on the state expansion compensation method,an improved method is proposed.The improved time delay compensation method achieves a more accurate solution of the average angular acceleration in the delay time period by pre-estimating the time delay,improves the compensation accuracy of the time delay,and improves the measurement accuracy of the hull deformation.The simulation results show that the estimated accuracy of the hull deformation angle is better than 0.1 cents after the time delay is compensated by this method.Then,the multi-model adaptive hull deformation estimation algorithm is proposed for the uncertainty of system parameters and the statistical characteristics of measurement noise.Based on the multi-model idea,a variable parameter multi-model algorithm is designed.By pre-estimating the main frequency,the problem of the main frequency uncertainty in the actual measurement is solved.Based on the Sage-Husa adaptive filtering idea,the adaptive volume Kalman filter algorithm is designed to track and estimate the measurement noise covariance matrix in real time,which effectively solves theproblem of statistical uncertainty of measurement noise.The effectiveness of the multi-model adaptive hull deformation estimation algorithm is verified by simulation.When the main frequency and the statistical characteristics of the measurement noise are unknown,the estimation accuracy of the hull deformation angle is better than 0.1 angular.Finally,the turntable simulation test is designed to verify the proposed algorithm.The experimental results show that the proposed time delay compensation method can effectively compensate the estimation error caused by time delay.The multi-model adaptive hull deformation estimation algorithm proposed in this paper can estimate the hull deformation angle effectively in the case where the statistical characteristics of the main frequency and the measured noise are unknown.