Analysis and assessment of the seat geometry comfort for public passenger vehicles

The geometric comfort of seats for public passenger vehicles has important influence on the riding comfort. The three-dimensional CAD model of human body and the fuzzy theory are comprehensively applied to evaluate the geometric comfort of vehicle seats. The human body CAD model with parametric function is built up, and a circular interference check method is proposed to match between a human body CAD model and a seat CAD model, by which the "virtual sitting" behavior of a passenger are implemented. A data collection of human joint angle is obtained automatically from the human body CAD model in sitting gesture through the application program interface of a CAD software. A three-level fuzzy assessment model for evaluating the riding comfort of vehicle seats is established. The three-level structure factor sets in the model are composed of genders, human body percentiles and joint angles, and the assessment sets are composed of series of vehicle seats with various design schemes. The assessment model can be used to quantitatively compare geometric comfort of different vehicle seats. A application software is developed on the CAD software platform, and the geometric comfort of vehicle seats can be evaluated automatically by the software.