Low Frequency Modal Management of a Premium Hatchback Car

Tactile feel of vehicle touch points and boom feel inside vehicle cabin are some of the important criteria of the customer choice while making the buying decisions in the dealership or on a test drive. This tactile and acoustic feel of a vehicle is majorly governed by the low frequency mode management achieved while designing the vehicle. Different parameters like inclusion of multiple powertrains on a vehicle program, choice of multiple way seating different at driver’s, front passenger’s and rear passengers’ seating positions, instrument panel and steering system layouts having higher torque delivery, suspension modes of the front and rear axles based on their articulation and degree of independency, global modes of the vehicle body, the cabin air cavity configuration and volume, etc. play a significant role in deciding this tactile and acoustic feel of the vehicle being designed. How these parameters were tuned and designed while developing a premium hatchback car has been elucidated with different subsystem development examples. The performance trade-offs considered while tuning all these parameters are discussed. How these parameters were revised in entire vehicle development cycle is outlined. The effect of this modal separation activity on full vehicle idle shake and road shake performance is explained.