Developing a Prototype Underwater LiDAR System

Light Detection and Ranging (LiDAR) is extensively deployed to capture dimensional information in a terrestrial environment. LiDAR designed for underwater deployment is in developmental infancy. This paper charts the justification, development and principle of operation of a prototypic under-water LiDAR system, developed for coastal applications. The developed prototype employs a 520nm green laser transceiver, with a high-speed ADC and in-situ industrial PC, performing real-time data processing and storage during deployments. A laser pulse is transmitted, and distance is calculated by analysing the received reflected waveform. The prototype was tested in two key locations: a public freshwater pool and the Derwent River estuary. A spatially accurate, partial 2D map of the public pool was obtained, thus establishing the system's ability to function underwater. A further deployment in the saltwater river estuary establishes the system's ability to operate in turbid water. Initial testing was successful and further development is underway.