Interferometric Synthetic Aperture Sonar in Pipeline Inspection

Abstract

Accurate and reliable inspection of subsea pipelinestraditionally requires the use of multiple sensors, which againhave different requirements for range and geometry. This makespipeline inspection a time consuming and costly process. The useof high resolution synthetic aperture sonar (SAS) can potentiallychange this substantially. Current state of the art interferometricSAS systems offer very high resolution imagery and bathymetryover a very wide swath. Mounted on an autonomous underwatervehicle (AUV), such a system can provide highly detailed datasets of a pipeline with just one or two passes ´ either fullyautonomously, or with operator supervision as desired. In June2009, a Kongsberg Maritime HUGIN 1000-MR AUV equippedwith a HISAS 1030 interferometric SAS performed such apipeline inspection mission in Western Norway. The paper willshow examples of the data recorded during the above mission.