1999 年 35 巻 4 号 p. 473-479
This study describes a system for analyzing drivers' visual direction. Rotational angular velocity sensors measured the head movements in the system we used in this study. A simple rotational machine using a pulse motor was produced to measure and verify the head movements. The eye movement was measured by an eye mark recorder. An ocular VOR characteristic was measured in order to verify the system. The relation between the head and eye movements was observed. We selected two conditions, which have significant effects on the visual direction in driving. These conditions were straight driving and lane change, both at legal speeds on an expressway. While driving, drivers' head movements and eye movements were recorded. The visual direction movements in straight driving were less as compared to lane changing. This result suggests that visual direction represents a specific characteristic of a driving situation. The measurement system for visual direction can be applied to evaluate safe driving.