Two field studies were conducted as part of the driver behaviour and traffic safety research section of the DRIVE programme. Both studies aimed at evaluating the visual attentional demand associated with the use of route navigation devices. Each study was conducted using members of the general public, driving specially adapted road vehicles in a real road environment. The first experiment, conducted in Loughborough, was designed in order to evaluate the visual workload associated with two modes of route information presentation: paper map or text display on LCD screen. Twenty subjects were required to drive the experimental vehicle along two urban routes in low volume traffic conditions. The second experiment was conducted in Berlin in order to evaluate the visual workload associated with two real in-vehicle displays, the LISB and travelpilot route guidance systems. Twenty-three subjects took part in the study. The visual workload associated with each experimental session was measured in terms of glance frequency and glance duration spent viewing the navigation display. These results were used to formulate matrices of visual performance which assess the "visual cost" of an in-vehicle display.
Abstract