Designing interior audio cues for hybrid and electric vehicles

Abstract

The advent of new propulsion technologies (e.g., hybrid, plug-in hybrid, fuel cell, and electric) changes the vehicle noise signature dramatically. Traditional powertrain sounds disappear and new sounds become audible, including those from alternative propulsion systems, power converters, and from the car's structure itself due to road noise, tire sounds, and vibration from the body frame. In the face of such developments, feedback to the driver regarding vehicle state is greatly changed, which may cause confusion and frustration. Our work explores the addition of sound cues to a vehicle's interior environment to increase drivers' aural feedback for states such as "ready to go", "systems off", and "alert". We discuss the design and evaluation of such cues for an electric vehicle, and relate this to background research in the areas of psychoacoustics, sonic branding, and auditory interfaces.