Comparative study of underwater reconstruction using imaging sonar and laser scanner

Abstract

This study presents preliminary results on the underwater object reconstruction utilizing imaging sonar and laser scanner for underwater three-dimensional (3D) recognition. Under water, the imaging sonar and laser scanner have different characteristics. The underwater imaging sonar uses acoustics to detect objects amongst various other things. It has the ability to measure long distances but with low accuracy and low precision. In contrast, laser scanners use active linelasers and an optic camera to measure the 3D position of an object. Although it is more accurate and precise than the sonar, the recognition distance is short because of the turbidity of water. As such, for underwater 3D recognition, it is necessary to select a scanning sensor considering the recognition task. To this end, this paper demonstrates the reconstruction results of imaging sonar versus those of the laser scanner and the subsequent analysis of the results.