Based On The Inertial Navigation Ocean Characteristic Element Measurement Research

Wave height,period,wave direction,peak frequency and wave energy density are the key characteristics of ocean motion environment.In this paper,the large scale wave flume is used to simulate the wave motion environment of the ocean in order to improve the prediction accuracy.The main contents are as follows:The influence of attitude calculation,external environment and sensor itself on acceleration signal is studied.To solve the problem of universal joint lock,four element algorithm is used to calculate the acceleration signal in full attitude.The distributed Kalman filtering algorithm is used to filter the acceleration signal to ensure the fault tolerance and stability of the sensor system,and to solve the interference problem of the external environment.Combined with the recursive average algorithm and the central processing algorithm to deal with the errors such as trend term and zero drift in the acceleration signal,the accuracy of the signal is guaranteed.For the acceleration signal with improved accuracy,the mathematical model of ocean wave motion is built and the numerical prediction is carried out.For the prediction of wave height,different mathematical models of time-domain and frequency-domain integration are used.The results show that with the increase of the number of integration,the errors generated in the integration process in time domain accumulate continuously,and the error range is within 7.2%.The integration in frequency domain can improve the accuracy of the error,and the error range is within 3.7%.The periodic value corresponding to the wave height is calculated by using the method of double fitting curve.The wave direction is calculated by counting the frequency of the corner of the velocity in the transverse and longitudinal directions.Wave spectrum algorithm is used to analyze the peak frequency and wave energy density of wave motion.The results show that with the same period,the wave energy density increases with the increase of wave height.With the same wave height,the period increases and the peak frequency increases.Based on the wave height instrument,the mathematical model of ocean wave motion is compared with the commercial SBF3-2 buoy.The results show that the prediction results of the mathematical model are consistent with those of SBF3-2.Under the action of regular wave,the relative error accuracy of wave height is increased by 0.2%.Under the action of irregular waves,the relative error accuracy of wave height is increased by 1.2%.