Miniature Model Examination as Human-body Dynamics for Seat Durability Evaluations

Abstract

While driving off-road vehicles, operators are exposed to whole body vibration that influences the fore-and-aft and vertical vibration. A dummy weight with no dynamic characteristics was installed on the seat as a load condition instead of a human body to evaluate the seat structure’s durability. A miniature model of a sitting human body was developed for seat durability evaluations. In a laboratory study, accelerations and forces in the vertical direction were measured at the seat face during whole body vibration in the fore-and-aft and vertical vibration. Four male subjects with body masses around 60 kg were chosen for the tests. They sat on a rigid seat with no backrest. A linear two-degree-freedom model, which was used to describe the dynamic behavior of a sitting driver, was assumed to be supported by two points: the floor and the seat face. The model parameters were identified by fitting the dynamic mass to the measured values. Good agreement was obtained between the experimental and simulation results. Based on the identified parameters, a miniature model of a seated human body was designed.