Frequency 4 Hz is an important frequency because
resonance of body trunk will be induced and a human
body is exposed to a high level of vibration at this
frequency. Based on these results, the spring Q was
adopted, as its resonance frequency was the lowest
one, according to the target specification. A damping
element was also adopted for the final experiment on
an artificial track, although transmissibility exceeded
1 at the resonance frequency. Based on the results of
tests on spring constant and transmissibility at
various resonance frequencies in Table 3, the
Tempered spring Q and damping element “c” were
adopted for the Oblique seat