In situ, three-dimensional imaging of centimeter-scale biophysical interactions and particle distributions with the deep-sea plenoptic camera EyeRIS

Many fundamental biophysical interactions in the ocean occur at small spatial and temporal scales (centimeters and seconds). These include animal locomotion, gelatinous plankton filter feeding, and fluid-structure interactions. A requirement for studying these processes is the ability to measure three-dimensional (3D) particle fields and deforming surfaces in situ. This is challenging due to the rapidly changing environment that is sparsely populated with particles of variable appearance. To address this need, we have recently developed and deployed an in situ deep-sea plenoptic imaging system named EyeRIS (Remote Imaging System). The system incorporates an industrial-grade plenoptic camera (Raytrix R26) and supporting infrastructure to provide real-time 3D particle and surface visualizations as both a cabled ROV-based instrument or a self-contained system on an AUV. A key advantage of EyeRIS is that it generates 3D information for objects from a single camera image, which simplifies machine vision tasks when compared to stereo camera systems. Here we describe the first at-sea deployment of the system on the MBARI MiniROV, show 3D particle distributions from 50 to 1000 m depth, and analyze the dynamics of gelatinous plankton swimming through particle fields.