Truck Front Cabin Mount Tuning for Cabin Noise Boom, Overall Interior Noise and Vibration Reduction

In today’s automobile industry refined NVH performance is a key feature and of high importance governing occupant comfort and overall quality impression of vehicle. In this paper interior noise and vibration measurement is done on one of the light truck and few dominant low frequency noise booms were observed in operation range. Modal analysis was done for the cabin at virtual as well as experimental level and few modes were found close to these noise booms. Vibrations were measured across the cabin mounts and it was found that the isolation of front mounts is not effective at lower frequencies. Taking this as an input, the mount design was modified to shift the natural frequency and hence improve the isolation behavior at the lowest dominant frequency. This was followed by static and dynamic measurement of the mounts at test rig level to characterize the dynamic performance and stiffness conclusion. Finally the interior noise and vibration measurement is carried out on truck fitted with selected mounts and substantial vibration, overall noise reduction and drastic boom noise reduction was achieved. This paper takes up a real-time noise scenario, its root cause analysis and establishment of final solution for same. It covers various activities like noise, vibration measurement and analysis, virtual and experimental modal evaluation, mount transmissibility evaluation followed by design and tuning for corrects stiffness, and finally verification at rig and vehicle level. Hence this works runs through complete flow of NVH development cycle. The cabin mount design patent registration is approved.