1.3.5 Evaluation of Oscillations by Humans
The quantitative evaluation of the oscillation comfort predetermines the effects of oscillations (and a reference test track). Serial investigations in this context have led to the guidelines VDI 2057 and ISO 2631. In these guidelines, a difference between the perception intensity and the duration of exposure exists.
Intensity of Perception of a Seated Human
The human body represents an oscillatory system, which can be approximated by an equivalent system for humans seated in the vehicle as shown in the figure.
Humans are oscillatory systems themselves. Hence it is humanly impossible to evaluate the effects of oscillation based only by their intensity, rather one tends to perceive oscillations of the same intensity but of different frequencies differently. As a consequence, a frequency-dependent evaluation exists between the physically measured values and subjective perception, which is different for individual parts of the body and different directions of action.