Composite Flextensional Transducers For Sensing And Actuating

A ceramic-metal composite flextensional transducer has been developed which integrates both sensing and actuating functions into a single device for the purpose of suppressing low-level vibration noise. This prototype sensor/actuator composite is capable of detecting and completely suppressing in real time small (<lμm) vibration displacements with low (<100gf) forces. The dynamic frequency range of the device spans from 100Hz to at least 2500Hz The actuator portion of the composite consists of a standard (11mm diameter 3mm thick) “moonie” transducer. The sensor is a separate piece of piezoceramic 0.1mm thick imbedded within the surface of the actuator. Vibrations are detected by the sensor; then via a feedback loop the vibration noise is suppressed by the actuator. Potential applications for this device include active optical systems rotor suspension systems and other low-level vibration suppression devices.