DISCOMFORT CRITERIA FOR SINGLE-AXIS VIBRATIONS.

A number of experimental investigations have been conducted to determine the fundamental relationships governing human subjective discomfort response to single-axis vibrations. The axes investigated were vertical, lateral, longitudinal, roll, and pitch, and the vibrations used were both sinusoidal and random in nature. Results of these investigations have provided the basis for (1) development of a scale of passenger discomfort that is common to all axes of vibration and (2) generation of discomfort criteria for each axis of vibration. The discomfort criteria are in the form of discomfort curves for each axis and for both types of vibration. Comparisons of the various single-axis criteria curves obtained in these studies as well as comparisons of these curves with the International Standards Organization recommendations are discussed. Finally, a transformation is presented that relates the discomfort scale to a measure of passenger acceptance (percent of passengers finding the ride environment uncomfortable).