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As autonomous vehicles with electric propulsion technology are introduced to the market, the customer expectations may change significantly compared to the conventional ownership models. It is expected that the customers' focus while commuting will shift from driver related to non-driver related tasks and, as a result, more isolation from the environment may be required. Among the many challenges in noise, vibration and harshness (NVH) for an autonomous-electric vehicle, the expectation is that road noise and component noise will require the most amount of development and refinement efforts. As such, a major focus on structure-borne road noise must be considered early in the vehicle development phase to avoid either costly changes late in the program or dissatisfied customers in the market.

The increased focus and demands on the reduction of fuel consumption and CO2 requires the automotive industry to develop and introduce new and more energy efficient powertrain concepts. The extensive utilisation of downsizing concepts, such as boosting, leads to significant challenges in noise, vibration and harshness (NVH) integration. This is in conflict with the market expectation on the vehicle's acoustic refinement, which plays an increasingly important role in terms of product perception, especially in the premium or luxury segment. The introduction of the twin charger boosting system, i.e. combining super and turbo charging devices, enables downsizing/speeding in order to achieve improved fuel economy as well as short time-to-torque, while maintaining high driving dynamics. This concept requires also extensive consideration to NVH integration. The NVH challenges when integrating a roots type supercharger are very extensive.

The automotive manufacturers today have to put more products faster to the market using shorter vehicle development time and also face significant challenges in vehicle design optimisation due to trade-offs mainly caused by increased focus on fuel economy and CO2 reduction. The market expectation on vehicle acoustics refinement is also increasing and plays a significant role in terms of product perception. With extensive introduction of enablers for improved fuel economy, like automated combustion engine stop/start system as well as down speeding/sizing and more aggressive shift maps for automatic transmissions, additional requirements and development tasks are needed for the noise and vibration (N&V) integration of a driveline. The scope of this paper describes the application of transfer path analysis techniques for low frequency driveline excitation at different low engine speed driving conditions focusing on engine start-up/shut-down events.

The competition in the automotive market enforces shorter vehicle development time in order to get products faster to the market. In addition the customer expectation on interior noise, vibration and harshness (NVH) refinement is increasing and has an important impact of the perception of the product. The focus on fuel economy and CO2 reduction leads also to significant challenges in the vehicle development, which may result in trade-offs for NVH performance. Today's direct injection turbo charged diesel and gasoline engines exhibit both high low-end torque, which gives the customer a pleasant drive quality and improved fuel economy. However, the NVH integration challenges become significant due to mainly structure borne noise transfer through both the driveline itself and the powertrain mounting systems. In addition, the impulsive noise due to the combustion process itself in especially diesel engines needs to be refined.