CONCLUSION
The results confirm that vibroacoustic methods allow monitoring dynamic parameters
of the vehicle. Those methods are very useful for precise observation of the signal realization
in time and frequencies domain. Obtained results enabled to analyse of the vibration
propagation to car body for different idle gear rotational velocity. Significant levels of the
vibration were recorded for the X and Z axes. The vibrations transferred to seat have
significant less value. It can be observed that for higher rotational velocity there is more high
frequencies vibration but very low values. This proves good vibration isolation in vehicle
cab. Based on the results it can be said only for vibration propagation from motor-car engine
for now but there are researches continuously conduct on the vehicle vibration. The assembly
and structure of car-body are very important in reduction of vibration transferred to driver or
passengers. Of course the materials used in vehicles construction are very important as well.
Modern technologies applied in manufacture of metallurgical products ensure high material
parameters, however, one must never exclude the possibility of a negative impact of the
inclusions from scrap processing (11) or changes in the material properties occurring in the
course of manufacture or resulting from repair works such as welding (12). It can affect safety
and comfort of ride.