In situ light-field imaging of octopus locomotion reveals simplified control.

Animals have developed many different solutions to survive, and these abilities are inspiring technological innovations in a wide range of fields including robotics. However, biologically inspired robots, especially those mimicking octopus locomotion, are based on limited in situ behavioural data owing to the complexity of collecting quantitative observations. Here we describe deployments of a remotely operated vehicle, equipped with a suite of imaging systems, to study the mechanics of locomotion in the octopus Muusoctopus robustus at the recently discovered 3,000-m deep Octopus Garden. Using a recently developed light-field imaging system called EyeRIS and an ultra-high-definition science camera, we were able to capture wide and zoomed-in views to characterize whole-animal gaits in a completely unconstrained environment across multiple individuals. Furthermore, the real-time volumetric data captured using EyeRIS yielded quantitative kinematics measurements of individual octopus arms during crawling, showing regions of high curvature and strain concentrated at distinct arm locations. Our results indicate that M. robustus crawling patterns showed several elements of simplified control, with implications for the design of future octopus-inspired robots. Further developments and deployments of technologies such as EyeRIS, coupled with capable robotic vehicles, will enable mining of the deep ocean for biological inspiration.