Usability engineering of "In Vehicle Information Systems" with multi-tasking GOMS

The developments in vehicle electronics and new services are supposed to promise more convenience in driving. The offers and ideas range from vehicle-related installations, such as accident alert, petrol station assistance, dynamic navigation and travel guide, to communication and entertainment services. There is one central design problem that is essential for achieving the main objective "safe motor vehicle driving", i.e. the use of the new service must not unduly distract the driver. In the following, we present a newly developed procedure to calculate the interference between main and additional tasks based on user models, which can already be applied in the early phases of system design. Thus, the driving tasks are described as ideal-typical resource profiles. There is only required a formative-quantitative task analysis in order to assess the secondary task using the well known and commonly approved method GOMS with some new extensions for multi-tasking.