North Hallsands Underwater Photogrammetry, 2019
Underwater photogrammetry, whilst generally accepted to be at an experimental phase of development, shows promise as an alternative or complementary dataset to hydroacoustic survey in very shallow-water environments, particularly for applications such as characterizing habitats including spawning grounds for rare fish species.
HydroSurv has been investigating the development of 3D models of underwater environments using photographic data collected using a small USV (mREAV) as the collection platform.
The company internally developed an underwater camera system for installation within the host USV moonpool, controlled by the vessel’s embedded control system – using distance or time intervals to trigger the camera shutter achieving sufficient overlap in the photographs to reconstruct the seafloor. This system was developed using commercially available off-the-shelf equipment running custom firmware to integrate the sensor to the vehicle, enabling high-optical quality photographs to be obtained at a sensible cost.