A new software package Nautilus has been developed which may help to reduce noise aboard vessels like the Collins Class submarine. It allows researchers accurately to position hydrophones and experiment models in a way that can be easily reproduced. Nautilus is being used to enhance Defence Science and Technology Organisationís underwater acoustics research facility in the Maritime Platforms Division in Melbourne (Australia).
Nautilus is used for water tank experiments, where the water tank has a surface area of 36 square metres and is four metres deep. When coupled with a commercial software and hardware data acquisition system known as MALICE, it is possible to develop accurate and detailed images of underwater acoustic patterns in the laboratory. MALICE's role is to make the sound measurements and also to process the data for analysis. The great advantages of the Nautilus software are that it provides a user-friendly graphical interface and provides sophisticated controls for the scanning hardware in three dimensions. This gives fast, convenient, and accurate control of position with millimeter precision. Nautilus can also be 'programmed' automatically to sweep a user-defined area or volume of any shape, periodically stopping at points defined by the operator to allow data to be acquired. This automates what is otherwise an error-prone and time-consuming operation.
As a result it is now possible quickly and easily to develop a detailed picture of underwater sound patterns, which can in turn be used to develop methods for reducing the noise profile of a vessel, such as the Collins.