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ACTIVE MICROVIBRATION CONTROL IN BASE-ISOLATED PRECISION MANUFACTURING FACILITIES WITH SMART STRUCTURE USING PIEZOELECTRIC ACTUATORS

In order to achieve more perfect vibration-free environment in base-isolated precision manufacturing facilities, a smart structure was tested for overall active microvibration control in a base-isolated 2-story steel frame building model of a 5×3×4 m external size and a 6,900 kg total mass which was supported by four multistage rubber bearings. In the building model, 20 piezoelectric actuators were attached to the columns and the beams, and four horizontal actuator units consisting of two piezoelectric actuators each and four vertical ones of the same type were installed between the bottom of the superstructure and the foundation. The controller was designed by a model-matching method. The tests showed that the smart structure could effectively control three-dimensional microvibrations generated in the building model and excited by external disturbances.