Vibration Control of Flexible S truetures Using Newly Developed Servosensor

This paper proposes a vibration control method for flexible structures using a new servo-type vibration sensor which can measurc both signals of velocity and displacement simultaneously under the low range of frequency. For controlling the vibration of flexible structures, it is necessary to measure velocity and displacement signals of these structures. When the structure is taller, its natural frequency is lower, and hence it is required to construct the sensor with a lower frequency of measuring range. The proposed sensor uses a positive feedback of the relative displacement for reducing its natural frequency actively. Therefore, the sensor with light mass and hard spring can be constructed for realizing this requirement. The effectiveness of the proposed sensor is demonstrated by both the simulation and experimental studies of controlling the vibration of a scaled bridge tower structure with a low natural frequency.