Zero-Emission Vehicles Sonification Strategy Based on Shepard-Risset Glissando

In this paper, we present a sonification strategy developed for electric vehicles aiming to synthetize a new engine sound to enhance the driver’s dynamic perception of the vehicle. We chose to mimic the internal combustion engine (ICE) noise by informing the driver through pitch variations. However, ICE noise pitch variations are correlated to the engine’s rotations per minute (RPM) and its dynamics is covered within a limited vehicle speed range. In order to provide the driver with extended pitch variations throughout the full vehicle speed range, we based our sonification strategy on the Shepard-Risset glissando. Such illusory infinite ascending/descending sounds enable to represent accelerations with significant pitch variations for an unlimited range of speeds. In this way, it is possible to conserve the metaphor of ICE noise with unheard gearshifts. We tested this sonification strategy in a perceptual test in a driving simulator and showed that the mapping of this acoustical feedback affects the drivers’ perception of vehicle dynamics.