Abstract
With the progress of Intelligent Transport Systems (ITS), driver's mental workload caused by the visual and auditory cognition has recently increased with the rapid spread of car navigation systems and other in-vehicle information devices. Under such circumstances, the accurate evaluation of the workload is important in order to develop in-vehicle information devices that do not menace the safety. In this paper, we present a basic idea to estimate the workload based on the driver's cognition, and show some experimental results for the estimation. The experimental data provide subjective and behavioral aspects of the workload, and clarify the quantification measure of the workload.
