Manufacturing of Physical Scale Models for Signature Reduction

The Physical Scale Model (PSM) has performed a critical role in the characterization and remediation of magnetic signatures in Navy ships. The properly executed PSM permits the accurate sizing and location of degaussing systems. To be of cost benefit, the PSM must be constructed before the final design of the Navy vessel, leading to many alterations and restarts for the PSM with the concurrent design changes in the Navy vessel. Because, up to this point in time, the PSM have been painstakingly constructed using highly trained craftsmen, the redesigns and restarts have made the use of the PSM approach very expensive. The PSM approach to characterizing magnetic signatures and degaussing system design is being supplanted by computer based finite element models that, while less accurate and less capable in measuring the permanent magnetization, are much more flexible and responsive to design changes at a lower cost. TRI/Austin proposes to develop, based on the permeability-thickness technique, a PSM fabrication process that will a) accurately model the magnetic signature of the Navy ship, b) be low cost and have a reduced lead time, and c) be highly flexible to design changes without major cost or schedule impacts.