Analysis for the Impact of the Geometric Parameters of Train Seat on Riding Comfort Based on Human Body CAD Models

Geometric parameters of train seat are key factors to influent riding comfort feeling of passengers. The impact of the geometric parameters of train seat on riding comfort can be analyzed effectively through the seated posture of human body. In CAD environment, the human body CAD models driven by Chinese human body size database are built by constraint equation and parametric modeling method based on a human prototype model. A circular interference check method is proposed to implement adaptive match between the human body CAD model and train seat CAD model. A data collection of joint angles of passengers with different genders and human percentiles are obtained automatically from the human body CAD models in sitting position. A three-level fuzzy comprehensive mathematics model for evaluating the riding comfort of train seat is established. In this model, the three-level structure factor sets are composed of genders, human body percentiles and joint angles, and the evaluation sets are composed of series of train seats with different sizes. The evaluating result is obtained through analyzing the data collection of joint angles of seated posture, which reflect the impact of the geometric parameters of train seat on riding comfort objectively and quantitatively. In this way, the rationality of the geometric parameters of train seat can be analyzed.