Sitting Strategy Analysis based on Driving Postures and Seating Pressure Distributions

Abstract

Sitting strategies which statistically represent preferred and comfortable driving postures can be used as reference data to design/evaluate an automobile interior layout. Although the previous research have identified the sitting strategies for various anthropometric dimensions of drivers, the classification method of sitting strategies was not objective and the effect of driver’s gender/occupant package layout (OPL) to the sitting strategy has not been clearly analyzed yet. The present study is intended to objectively identify the sitting strategies based on various drivers’ preferred driving postures and seating pressure distributions. Forty drivers’ preferred driving postures and their seating pressures in 3 different OPL conditions (coupe, sedan, and SUV) were measured by a motion capture system and pressure mat. Next, the sitting strategies were classified by a cluster analysis, and the effects of driver’s gender and OPL condition to the sitting strategies were statistically analyzed. As a result, the sitting strategies for upper-body were identified as erect (33% of drivers were preferred), slouched (41%), and reclined postures (26%). The number of drivers who preferred erect posture, female drivers was more than twice that of male drivers; on the other hand, the number of drivers who preferred reclined posture, male drivers were more than twice that of female drivers (p < .05). Moreover, 84% of drivers preferred knee bent strategy in SUV condition because the SUV condition has higher seat height than coupe and sedan condition (p < .05). Both the identified sitting strategies and the factors to affect sitting strategies would be of use as considerable information in an ergonomic design/evaluation of automobile interior layout.