HYDRO 2016 Paper 7A5

Object detection by ALB

Mark Sinclair, Dariusz Lejtman, Hugh Parker

Object detection by Airborne LiDAR Bathymetry (ALB) requires a number of criteria to be satisfied: the data must be dense enough to illuminate a particular feature, the laser power, water clarity, depth of water, object reflectivity and receiver sensitivity must be adequate to detect the feature, processing software needs to be able to select the feature and processes including quality control systems need to be in place to retain the feature and discriminate seabed features from noise.

Object detection is specified for IHO Order 1a and Special Order Hydrographic surveys and object detection is often included in scopes of work for hydrographic surveys. However, ALB object detection requirements are often not clearly specified, or requirements from acoustic surveys are incorrectly used.

This paper examines the empirical results of ALB object detection trials, in particular the results of detecting 1 m and 2 m cubes. It reviews the requirements for ALB object detection and proposes an appropriate scope of work for object detection by ALB.