This paper focuses on investigating the drivers' characteristics when using the communication services of in-vehicle information systems, based on the modality of the human interface and the mental stress imposed. In the experiment, a simple driving simulator was utilized and the subjects were required to perform two different tasks (a tracking task to simulate usual driving and a secondary task to simulate the use of communication services) simultaneously. The secondary task was based on mental arithmetic using a display method (visual or auditory display) and input method (touch or verbal input). The subjects' characteristics were analyzed and evaluated in terms of eye movement, control performance, subjective rating and performance of the secondary task. The results imply that the drivers' mental strain can be decreased by appropriate selection of the modality of the human interface based on the level of the mental stress when using the communication services. (A*)
Abstract