Navigation through fog using stereoscopic active imaging

Autor: David H. Tofsted, Wendell R. Watkins, Jay B. Jordan, John O. Merritt, V. Grayson CuQlock-Knopp
Rok vydání: 2000
Předmět:
Zdroj: SPIE Proceedings.
ISSN: 0277-786X
DOI: 10.1117/12.389357
Popis: Navigation, especially in aviation, has been plagued since its inception with the hazards of poor visibility conditions. Our ground vehicles and soldiers have difficulty moving at night or in low visibility even with night vision augmentation because of the lack of contrast and depth perception. Trying to land an aircraft in fog is more difficult yet, even with radar tracking. The visible and near-infrared spectral regions have been ignored because of the problem with backscattered radiation from landing light illumination similar to that experienced when using high beam headlights when driving in fog. This paper describes the experimentation related to the development of a visible/near-infrared active hyperstereo vision system for landing an aircraft in fog. Hyperstereo vision is a binocular system with baseline separation wider than the human interocular spacing. The basic concept is to compare the imagery obtained from alternate wings of the aircraft while illuminating only from the opposite wing. This produces images with a backscatter radiation pattern that has a decreasing gradient away from the side with the illumination source. Flipping the imagery from one wing left to right and comparing it to the opposite wing imagery allows the backscattered radiation pattern to be subtracted from both sets of imagery. The use of retro-reflectors along the sides of the runway allows the human stereo fusion process to fuse the forward scatter blurred hyperstereo imagery of the array of retro-reflectors while minimizing backscatter. The appropriate amount of inverse point spread function deblurring is applied for improved resolution of scene content to aid in detection of objects on the runway. The experimental system is described and preliminary results are presented to illustrate the concept.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Databáze: OpenAIRE