Towards Repeatable, Deterministic NVG Stimulation

Charles J. Lloyd – Principal Staff Engineer
Steven G. Nigus – Engineering Director
Brian K. Ford – Lead Engineer

Visual Simulation Systems
FlightSafety International

From the Proceedings of the 2008 IMAGE Society Annual Conference, St. Louis, Missouri.

Practical Geometry Alignment Challenges in Flight Simulation Display Systems Towards Repeatable, Deterministic NVG Stimulation

Abstract

Night vision goggle (NVG) training is an increasingly important element of pilot training syllabi. The training is more effective if the students can use their own goggle sets during flight simulator-based training. This creates the need to stimulate the actual goggles using the simulator displays. We have successfully used CRT projector-based display systems for a number of years to stimulate goggles. However, these systems have presented significant challenges during system installation, integration, and recurring calibration. The emergence of viable new non-CRT display types with differing radiometric performance further complicates these issues. This paper presents a range of system improvements leading to improved stimulation repeatability and determinism. We present our methods for quantitatively relating measured NVG device responses to real-world radiance values. These methods are used to compare the capabilities and limitations of several display types. We describe our new illumination model that is traceable to published real-world sky radiance and lunar illumination characteristics. We have developed a set of recommendations for instructor operating station (IOS) illumination controls that relate simulated scene illumination to conditions reported in standard pilot briefings, which provides a familiar, natural training framework.