Analysis of Driver's Head Tilt Using a Mathematical Model of Motion Sickness

TL;DR

This paper investigates how a driver's head tilt strategy affects motion sickness using a mathematical model and real-world measurements, showing that tilting the head inward reduces sickness incidence.

Contribution

It introduces a mathematical model linking head tilt to motion sickness reduction and provides empirical evidence supporting the benefit of driver head tilt strategies.

Findings

Head tilting inward reduces motion sickness incidence.

Drivers experience less motion sickness than passengers.

Imitating driver head tilt can reduce passenger motion sickness.

Abstract

It is known that car drivers tilt their head toward the center of a curve. In addition, drivers are generally less susceptible to carsickness than are the passengers. This paper uses a mathematical model to investigate the effect of the head-tilt strategy on motion sickness. It is shown that tilting the head in the centripetal direction reduces the estimated motion sickness incidence (MSI), defined as the percentage of subjects who vomited. In addition, the head movements of both drivers and passengers were measured in a real car. It is also shown that the estimated MSI of the drivers is smaller than that of the passengers. Experimental results presented in previous studies demonstrated that the severity of motion sickness was reduced when passengers imitated the head tilt of the driver. These results strongly suggest that the driver's head tilt reduces motion sickness, and this can be understood as a subjective vertical conflict.