Abstract
In this paper, the formulation of human occupant and safety belt system is presented to perform vehicle passive safety analysis through computer simulation. The human body mathematical model is built by using multibody system dynamics, and the safety belt system is modeled by introducing three new concepts of equivalent stiffness, equivalent redundancy, and equivalent slipping coefficient as well, to account for belt dynamic force characteristics, system redundancy and belt slipping on human body surface respectively. Based on the models of human occupant and safety belt system built in this paper, the responses of Hybrid II dummy in vehicle front crash accidence are simulated, and some conclusions relating the design of belt system and vehicle cab are reached.