Underwater surface recovery and segmentation

The underwater environment presents many challenges for robotic sensing including highly variable lighting and the presence of dynamic objects such as fish and suspended particulate matter. The dynamic six-degree-of-freedom nature of the environment presents further challenges due to unpredictable external forces such as current and surge. Despite these challenges the aquatic environment presents many real and practical applications for robotic systems. A common requirement of many of these tasks is the need to construct accurate 3D representations of specific environmental structures. In order to address these needs we have developed a stereo vision inertial sensing device that has been successfully deployed to reconstruct complex 3D structures in both the aquatic and terrestrial domains. The sensor combines 3D information, obtained using stereo vision algorithms, with 3DOF inertial data to construct 3D models of the environment. The resulting model representation is then converted to a textured polygonal mesh for later processing. Semi-automatic tools have been developed to aid in the processing of these representations. Reconstruction and segmentation of coral and other underwater structures obtained with the sensor are presented.