Recently, digital transformation in marine construction—such as unmanned operations using remotely operated underwater construction machinery—has been gaining attention for its potential to improve productivity, efficiency, and safety. To enable remote operation of underwater backhoes, accurate position information is essential. However, since the global navigation satellite system (GNSS) cannot be used underwater, position data must be obtained using underwater acoustic signals. In shallow water, where marine construction typically takes place, conventional underwater acoustic positioning faces challenges and often becomes unstable due to strong multipath effects caused by signal reflections. To address this issue and achieve precise underwater positioning, our research group has developed a signal processing technology that filters out unnecessary reflected waves by using database matching. This paper presents an overview of our newly developed multipath-resilient underwater acoustic positioning system and its application in a guidance system for underwater backhoe operations.
Yoshihara et al. (2025) studied this question.