Distance and Clearance Perception Using Forward-Looking,Vehicular Television Systems *

Abstract

During off-road navigation, drivers often must make size, distance, and clearance judgments of terrain features and obstacles in order to choose safe navigational routes. These same judgments must be made in the teleoperation of land vehicles using forward-looking television systems. This study evaluated how well subjects perceived size, distance, and clearance using monochrome and color television systems. Thirty-eight subjects (Ss) estimated the size, distance, and separation of two obstacles using video imagery produced by a forward-looking, vehicle-mounted camera. Results indicate that Ss typically overestimated distances, and when in error judging clearance, tended to overestimate the gap between the objects. These biases were expected due to the well documented minification effect of television using standard lenses. More surprising was the somewhat larger bias evidenced by Ss using color versus those using monochrome imagery. This paper will describe the research methodology, the results obtained, potential reasons for the results, discuss the plans for continuing research in this area, and assess the implications these findings may have on teleoperated vehicle design.