Owing to the uneveness of the ground the crew of a vehicle is
exposed to mechanical vibrations which represent a significant
strain to the human body. This strain can result in impairment of
comfort, in nausea, inability to operate the vehicle and in severe
health disorders.
Recommendations and standards are based on the fact that
acceleration magnitude is perceived to a greater extent within the
range of low frequencies and that therefore is only practical to
study frequencies up to 100 Hz. The assessment criteria contained
in recommendations are based on sinusoidal vibrations, in fact, the
vibrations of vehicle are irregularly distributed. For that reason
it is necessary to carry a frequency-analysis while the vehicle is
in operation.
Furthermore, the attempt is made to establish correlations
between road surface-condition, speed, inflation pressure,
tyre-type and load, by varying the a/m influences.
