Abstract
A bicycle is a popular vehicle for a lot of people by the low price and the easy maintenance in comparison with a car and a motorcycle. In order to expand the popularity of the bicycle, improvement of the ride comfort is necessary. In this study, subjective evaluation tests and acceleration measurements using many kinds of bicycle were performed to quantify the ride comfort and obtain which part and frequency have high contribution to the ride comfort. In the subjective evaluation test, the vibration feeling of the saddle was found to correlate with the ride comfort very much, and through the acceleration measurement of the saddle, both vibrations of vertical and horizontal directions affect the ride comfort. But the influence of the vertical vibration was higher than that of the horizontal vibration. The ride comfort calculation method was developed by considering these characteristics. Next, to verify the reliability of the ride comfort calculation method, saddle vibration of a city bicycle was reduced by modifying the saddle spring and the frame structure. As a result, the ride comfort was evaluated better and the degree was very similar with the predicted level by the ride comfort calculation method. From these results, the ride comfort of bicycle could be quantified with high reliability.
