VIBRATION ANALYSIS MODEL DEVELOPMENT AND INVESTIGATION OF ROAD SURFACE EVALUATION INDEX FOR BICYCLES WITH REAR INFANT SEATS

Abstract

 In recent years, the expansion of cycle tourism and daily bicycle use has been promoted in the context of tourism region development. Although ride comfort for bicycle riders has been studied, there has been limited consideration of bicycles with infant seats, which are commonly used by families for commuting and shopping. This study focuses on rear infant seats and aims to characterize their vibration properties through on-road experiments, develop a model for vibration analysis contributing to pavement evaluation, and define a pavement evaluation index. The results indicate that dominant vibrations occur in the 6.4 - 10.7 Hz range at the rear infant seat, and high-frequency components above 20 Hz are attenuated due to the effect of rider mass. Furthermore, vibration analysis using the proposed three-degree-of-freedom model, which incorporates the observed vibration characteristics, reproduced trends in vibration acceleration and frequency response functions similar to the measured values, demonstrating high fidelity in representing road-induced vibrations.