The aim of this study is to experimentally assess the potential risk on road safety when using a handsfree phone while driving in situation of interactive conversation. The exploratory research was carried out on an interactive driving simulator, and was based on about 40 routes performed by 17 subjects. In a first step, the observation of speed variations induced by the use of a phone brings two types of reaction into prominence: (1) no effect; and (2) a more rigid driving behaviour. This behaviour is shown by a speed increase or decrease, or by a longer period of oscillations around the required speed, or even by a total loss of speed control. These reactions were compared to answers to a questionnaire asking for the causes to a questionnaire asking for the causes of difficulties encountered and how the driving task was disturbed by phoning while driving, and vice versa. This comparison has allowed to see how the subjects have managed the dual task. In most cases, they have used a time sharing strategy during which the main task, namely driving, is often perturbed by the second one, that is to say phoning. (A)
Samenvatting