Haruka ASADA

A large number of vibrations are applied to a railway vehicle while it is running, and the natural vibration phenomenon occurs when the frequency of the vibration approaches the natural frequency of the vehicle itself. It is a common phenomenon but it is also an issue to prevent it from occurring, and it is necessary to clarify each natural vibration mode of the vehicle. In this study, we performed a running experiment by using a railway roller rig. By PSD analysis of the vibration acceleration at each measurement point, it is clear where the natural vibration phenomenon occurs at lateral and we know the experimental value through running experiment. We also modeled horizontal 6 degrees of freedom of the roller rig model, calculated the natural frequency, and grasped the theoretical natural vibration mod by using numerical analysis software. By comparing the theoretical value and the experimental value, the natural vibration analysis method was established.

In recent years, research and development of personal mobility, which is said to be a compact single-seat mobility support device as one of the next generation transportation, has been promoted by companies and research institutions. Many of the vehicles that have been developed have a distance between the driver's boarding position and the road surface, and there are riding methods such as standing and sitting. In this study, wheelchairs and self-propelled vehicles that the driver himself drives are defined as a part of personal mobility, and the vibration analysis that affects the driver rather than driving and the effect on ride comfort are examined. In addition, the natural frequency obtained from the impact test is compared with the theoretical value.