Ship heave measurement method based on sliding adaptive delay-free complementary band-pass filter

Abstract

Accurate measurement of heave motion plays an important role in multi-beam echo sounding system and seabed feature recognition. Currently, scholars have put forth two primary methods for measuring ship heave, namely employing Kalman filtering and traditional high-pass filters. Nevertheless, the precision of heave measurement is somewhat compromised due to challenges in accurately establishing ship heave dynamics models, reliance on empirical values or peak detection ranges, and the impact of time-delay errors. To enhance the precision of heave motion measurement, this paper introduces a method based on a sliding adaptive delay-free complementary band-pass filter. The method adaptively acquires cutoff frequencies of band-stop filters within different windows and derives the transfer function of the non-delay complementary band-pass filter based on complementarity. To validate the efficacy of the algorithm, this study conducted experiments utilizing two distinct sets of shipborne data acquired on September 18, 2023, and September 22, 2023. The proposed method significantly improved accuracy compared to other methods, reducing reliance on prior knowledge or empirical values, and mitigating time-delay errors, thus achieving high-precision heave motion measurement.