Abstract
Motion by a passenger seated on a 6-axis motion base has been measured with a motion capture system while the passenger is exposed to motion that simulates lateral sway of a vehicle. The relationship between the motion index calculated from the motion of the physical parts of the passenger and the subjective evaluation (acceptable or unacceptable) has been analyzed statistically using logistic regression. The result suggests that the angular velocity of skull is a major factor that influences subjective evaluation of acceptability.