Designing In-Cab Sound of Vehicles as per the Customer Driving Pattern on Roads

Vehicle refinement from point of view reduction in its Noise, Vibrations and Harshness (NVH) affects customer’s buying decision and it also directly influences his/her driving experience on road at different speeds. Customer voice, however, indicates that a traditional process of developing design solutions is not aligned with the customers’ expectations. Traditionally the load cases for NVH development are focused only on quietness of passengers’ cabin at idling and in 3^rd gear wide open throttle cruising on smooth roads. In reality, the Driver of a premium sedan car or a Sports Utility Vehicle (SUV) or a Compact Utility Vehicle (CUV) expects something different than merely the low sound pressure level inside the cabin. His/her driving pattern over a day plays a crucial role. A vehicle-owner wishes to balance various attributes of the in-cab sound and tactile vibrations at a time. A single value Customer-Voice-Index (CVI) is developed here based on study of critical drive load cases faced by common customers classified with C: Critical to customer perception; O: Occurrence of each drive load case throughout running of the vehicle and D: Duration of each load case. Cost to Benefit Ratio of various design solutions then could be evaluated effectively in a vehicle by monitoring its CVI. This is demonstrated here on a new SUV to give the desired sound character of the vehicle with low cost solutions and thus make the customers fall in love with it during cruising on highways at high speeds.