One of the major concerns surrounding the use of many advanced in-vehicle devices is additional workload and the consequent effect on driving performance. This paper reports on a practical quantitative assessment technique applicable to in-vehicle displays. One simple measure of distraction is provided by eye glance behaviour (i.e. where the driver looks and for how long) while absorbing information from an in-vehicle display. It has even been suggested that designers should aim for a maximum of 2 seconds "eyes off the road" time. Whilst it may be too early to set such absolute values (even if the driving conditions and subject groups could be specified), it is possible to add to existing data by comparing traditional and new devices. In this paper, equipment and methods are described to monitor a driver's eye glance behaviour during normal road driving whilst interacting with a variety of in-vehicle devices. Measurements are reported from subjects reading a speedometer, using a radio snd using a cassette player. These are compared with similar measurements from the same subjects using a commercially available in-vehicle information system. (A)
Abstract