Abstract
Recently, railway vehicle is extensively lightened since this lead to the speed-up. However, the simplification of car body shell structure and alternative light material causes the deterioration of the body rigidity, and leads to the increase in a vertical bending vibration of the car body. In addition, the deterioration of riding comfort concerns to this issue, because the natural frequency of the bending 1^<st> vibration overlaps with human's uncomfortable sensitive frequency band. Therefore, the objective of this research is to reduce bending 1^<st> vibration by embedding piezo-electric actuator in the actual lightweight railway vehicle car body.