Adherence to Component Level NVH Targets

NVH-Performance Cascaded

Targets to meet Vehicle-level NVH performance once get cascaded down to those related to components and subsystems, a question comes to mind how much religiously we should adhere to each and every line item of our the target Book?

Challenges to meet the ideal targets generally become a tough task for vehicle designers from views of weight & cost constraints as well as time of development. For example, for a passenger vehicle-Body to be NVH-signed off at the digital simulation phase , the below cascaded targets are really ambitious and benchmarking studies of many International vehicles do not show that these targets are absolutely adhered in the full frequency range at all power-train and suspension attachment points.

Should we then divide hundreds of Targets of a newly developed vehicle into following 3 baskets? 1. . Absolutely mandatory targets ●2. ....Desirable Targets they have a good tolerance band based on Industry practices with available technology ●3. .Targets only to be Monitored .....they are like Guidelines for developing a good or an ideal vehicle) ---- otherwise they can be ignored if the vehicle as a whole is acceptable subjectively to be good for NVH in a particular class of vehicles in competition Till Engineering sign-off, NVH Managers have then to fight with the Vehicle Integration Heads for the best possible combination of the sub-system and components to deliver a desired comfort for passenger under different operating conditions . There will be a good debate among them to draw a boundary line between the mandatory and the desired targets .. ... and an optimum balance is needed ... between the vehicle cost and its NVH refinement