Study on the Sound Design of a Sporty Vehicle

From a Noise Vibration Harshness (NVH) perspective, electric vehicles represent a great opportunity since the noise of the combustion engine, dominant in many driving conditions, is no longer present. On the other hand, drivers accustomed to driving cars with a strong personality (for example typically sporty ones) may perceive "silence" as a lack of character. Our internal study, conducted with a jury of people, has in fact already shown that for half of customers silence should characterize (Battery Electric Vehicle - BEV) vehicle; but, at the same time, the other half of the jury expects feedback from the vehicle while driving. The silence inside the passenger compartment, from an NVH point of view, can therefore be compared to a blank sheet of paper, on which, if desired, sounds designed to satisfy the driving pleasure expected by the customer can be introduced.

Starting from this scenario, the paper describes:

• the approach adopted to define how many and what are the levers to design a good sound for our customers driving a sporty vehicle
• the engineering guidelines to achieve the desired sound

The process followed is a structured flow based on:

• several focus groups, with experts from different company departments, to define the main dimensions of the sound that can characterize a BEV sporty vehicle for our customers
• subjective evaluations, expressed according to aspects coming from the focus groups, based on acoustic traces recorded on different BEV vehicles with sound enhancement
• analysis of objective data and comparison with the main results of the analysis of subjective data

As a conclusion and main result, engineering guidelines and directions will be presented to create a good sound for a BEV sport vehicle.