Fast Visible Detection Studies Using Signature Maps

The Navy wishes to study trade-offs in aircraft maintenance versus visible and near IR detectability in the use of glossy paint finishes. We propose a novel simulation survey technique based on forward ray tracing which will greatly increase the possible space of vehicle, sun and observer positions for this trade study. Forward ray traces build a radiance map for all observation directions, essentially calculating the signature in all view directions simultaneously in an extremely fast and efficient manner. Forward ray traces are also superior to other imaging techniques at identifying strong specular glints. Starting with a modern signature code which has highly accurate glint modeling, we will modify its forward ray trace capability to handle aircraft illuminated by the sun, skyshine and earthshine. We will also add a generic visual detection interface which will support a variety of models, starting with the VIDEM and Georgia Tech Visual (GTV) models. BRDF and DHR measurements will be performed on materials of interest, and all measurements and calculations with be verified through a testing process. This will lay the groundwork for a full vehicle study to be performed in Phase II.