Development of a Novel Hybrid Method to Evaluate Driving Comfort in an All-terrain Vehicle Using Transfer Path Analysis and Transfer Function Analysis

Vehicle comfort has become a buzzword in the automobile sector and continuous research is going on in this domain. Every automobile manufacturer would like to take the lead in vehicle comfort so as to attract more customers. Noise, vibration and harshness (NVH) testing is very important for improving the driving comfort of a vehicle. Driving comfort is directly related to the driving ability and health of the driver. Many international organisations have laid down guidelines for measuring driving comfort and categorise it in a range from comfortable to extremely uncomfortable. The present study adopts an experimental approach to determine the driving comfort in all-terrain vehicles (ATVs) by measuring frequency-weighted root-mean-square (RMS) accelerations at all the driver contact points in three mutually perpendicular directions as per the guidelines laid down in ISO 2631-1:1997 and ISO 5349-1:2001. The low-amplitude high-frequency engine vibrations are attenuated by performing transfer path analysis (TPA) of the vehicle roll cage before and after design modifications. The performance of the engine isolator mount is evaluated by carrying out transfer function analysis (TFA) of the active and passive engine mount vibrations. A novel hybrid approach comprising the TPA and TFA methods is used to attenuate the engine vibrations. The test result shows the effectiveness of the design modifications at the footrest, whereas there is moderate to low effectiveness at the steering and seat, respectively.