Using Monocular Vision and Human Body Priors for AUVs to Autonomously Approach Divers

Direct communication between humans and autonomous underwater vehicles (AUVs) is a relatively under-explored area in human-robot interaction research, although many tasks (e.g., surveillance, inspection, and search-and-rescue) require close diver-robot collaboration. Suboptimal AUV positioning relative to its human collaborators can lead to poor quality interaction and lead to excessive cognitive and physical load for divers. In this paper, we introduce a novel method for AUVs to autonomously navigate and achieve diver-relative positioning to begin interaction. Our method is based only on monocular vision, requires no global localization, and is computationally efficient. We present our algorithm and its implementation on board a physical AUV, performing extensive evaluations in the form of closed-water tests in a controlled pool. Our results show that the proposed monocular vision-based algorithm performs reliably and efficiently, operating entirely on-board the AUV.