Department of Navigation and Marine Hydrography, Faculty of Navigation and Naval Weapons, Polish Naval Academy, ul. Śmidowicza 69, 81-127 Gdynia, Poland.
Sensors (Basel). 2022 Mar 25;22(7):2530. doi: 10.3390/s22072530.
This article presents a novel method for validating compass devices. To this end, the post-processing method was used, i.e., the previously recorded vessel's heading from three compass devices was applied. A spectral analysis of the recorded heading in the frequency domain was conducted by applying the fast Fourier transform method. Based on a synthetic summary of the results of spectral analysis in the heading error frequency domain, the factors causing errors of low-frequency compass device indications, manifested by the vessel's yawing due to the vessel steering errors on the pre-determined course and the external factors causing total drift of the vessel, were eliminated. To this end, the convolution functions in the form of the sum of input signals with an impulse response, i.e., the filter with a finite impulse response (FIR) and with an infinite impulse response (IIR), were used to compare the effectiveness of the methods estimating the vessel's heading. The final stage of the research process in the methodology applied was the use of state- and time-discrete Markov processes whose task is to determine the matrices of the intensity of transitions between the states of individual compass systems.
本文提出了一种验证罗盘设备的新方法。为此,使用了后处理方法,即将先前从三个罗盘设备记录的船舶航向应用于此方法。通过应用快速傅里叶变换方法,对记录的航向在频域中的进行了频谱分析。基于航向误差频率域中综合总结的频谱分析结果,消除了由于船舶在预定航向上的转向误差导致船舶偏航以及外部因素导致船舶总漂移等低频罗盘设备指示误差的因素。为此,使用了卷积函数的形式,即输入信号与脉冲响应的和,即具有有限脉冲响应(FIR)和无限脉冲响应(IIR)的滤波器,以比较估计船舶航向的方法的有效性。在应用的方法学的研究过程的最后阶段,使用了状态和时间离散马尔可夫过程,其任务是确定各个罗盘系统状态之间的强度转移矩阵。