This report describes the evaluation of the prototype of the intelligent Instrumented CAr for Computer Aided Driving (ICACAD) car. The evaluation consisted of two field experiments conducted in The Netherlands. One experiment was carried out in a city environment. The other experiment was performed on open roads. The essential comparison in both experiments was made between an integrated and a non-integrated form of intelligence. The risk of an information overload to the driver is reduced in the integrated form. This is done by scheduling potential messages originating from specific support components according to their priority. The effects of both forms of intelligence on driving behaviour were compared to baseline driving performance without giving support. Subjective and physiological (heart rate) estimates of mental stress while driving were also obtained. Beneficial effects on driver behaviour were generally found as a result of both the integrated and non-integrated forms of support. In particular, reductions inboth driving speed and in the occurrence of very short following headwayswere found. Both experiments showed with respect to the drivers' estimates of mental load, that the non-integrated support caused higher mental load levels than the integrated support did.
Abstract