Abstract:

It has been documented that use of an In-Vehicle Information System [IVIS] can impair driving perfor-mance. In general, voice-controlled IVISs are considered less distracting than those controlled by touch and are therefore considered as less interfering with the driving task. However, certain types of voice-controlled IVISs may be better (less distracting) than others. In this study, we evaluated two variants of a voice-controlled in-vehicle music retrieval and navigation system in order to investigate the effect of a common affordance where the IVIS controls the pace and timing of a multi-turn interaction. Participants were asked to drive various scenarios in a simulator while engaging with either a user-paced IVIS or a system-paced IVIS. Driving performance measures and IVIS usability measures were collected. Our results indicated that when the driving task imposes higher mental effort (e.g., on a curved roadway), the user-paced IVIS was found to be more effective and safer to use, whereas when the driving task imposes low mental effort (e.g., on a straight roadway), the user-paced and the system-paced IVIS was less effective but still safer.