A dolphin-inspired compact sonar for underwater acoustic imaging

Abstract

Underwater imaging sonars are widely used for oceanic exploration but are bulky and expensive for some applications. The sonar system of dolphins, which uses sound pulses called clicks to investigate their environment, offers superior shape discrimination capability compared to human-derived imaging sonars of similar size and frequency. In order to gain better understanding of dolphin sonar imaging, we train a dolphin to acoustically interrogate certain objects and match them visually. We record the echoes the dolphin receives and are able to extract object shape information from these recordings. We find that infusing prior information into the processing, specifically the sparsity of the shapes, yields a clearer interpretation of the echoes than conventional signal processing. We subsequently develop a biomimetic sonar system that combines sparsity-aware signal processing with high-frequency broadband click signals similar to that of dolphins, emitted by an array of transmitters. Our findings offer insights and tools towards compact higher resolution sonar imaging technologies.

Anthropogenic activity, hydrological regime, and light level jointly influence temporal patterns in biosonar activity of the Yangtze finless porpoise at the junction of the Yangtze River and Poyang Lake, China

“…As top predators in aquatic trophic networks, the size and distribution of cetacean populations are excellent indicators of habitat health ( Echeverria et al, 2022 ; Würsig, 1989 ). In addition, cetaceans play key functions in ocean and freshwater ecosystems, including the facilitation of carbon and nutrient cycling ( Savoca et al, 2021 ) and regulation of food webs ( Springer et al, 2003 ).Cetaceans are also promising sources for cancer suppression research and can contribute to the development of future targets for human cancer therapies ( Tollis et al, 2019 ) and are important subjects for the investigation of evolution ( Goldbogen et al, 2019 ; Goswami et al, 2022 ) and bioinspired innovation ( Capus et al, 2007 ; Vishnu et al, 2022 ).…”