Underwater environment reconstruction using stereo and inertial data

The underwater environment presents many challenges for robotic sensing including highly variable lighting, the presence of dynamic objects, and the six degree of freedom (6DOF) 3D environment. Yet in spite of these challenges the aquatic environment presents many real and practical applications for robotic sensors. A common requirement of many of these tasks is the need to construct accurate 3D representations of structures in the environment. In order to address this requirement we have developed a stereo vision-inertial sensing device that we have successfully deployed to reconstruct complex 3D structures in both the aquatic and terrestrial domains. The sensor temporally combines 3D information, obtained using stereo vision algorithms with a 3DOF inertial sensor. The resulting point cloud model is then converted to a volumetric representation and a textured polygonal mesh is extracted for later processing. Recently obtained underwater reconstructions of wrecks and coral obtained with the sensor are presented.