Influence of engine noise in cabin on controlling the vehicle speed

Electric-powered vehicle (EV) have been popular in recent years. This transition makes interior noise more quiet by the reduction of the engine noise. On the other hand, the engine noise does not deteriorate only the sound quality in cabin, but the noise may have a role as the auditory information at driving. In this study, we then investigated an influence of the engine noise on controlling the vehicle speed through subjective test using a driving simulator. In the test, vehicle speed controlling task was given to the participants without speed meter at acceleration, deceleration and cruising conditions. As the presented sounds at these driving conditions, three conditions were prepared (1. IC condition with engine and background noise, 2. E condition with background noise, 3. S condition without any noise). As the result, the vehicle speed controlling ability was high in the IC condition especially at the acceleration and cruising conditions. Through the result, engine noise was clarified to make controlling vehicle speed easier and considering this characteristic for electric vehicle sound design was found to be important for safety driving.