Structural Bracing for Seismic Energy Dissipation

Not Available Piezoceramics have been gaining increasing popularity in structural control. Their high energy density permits fabrication of actuators with very high control authority, yet relatively little mass of volume. These properties make piezoceramics ideal for precision positioning elements (e.g., stabilization of optical gun sights), structural damping, precision controlled valves (e.g., environmental control systems) and noise control (e.g. vehicle interior quieting). Unfortunately, piezoceramics have some undesirable properties which complicate their use. In common usage, the devices are bonded to the surface of the structure and actuated using d31coupling. This yields a device which cannot control torsional or twist modes of orthotropic structures, limiting the usefulness of piezoceramics in applications in which torsional motion is important, including missile bodies or fins, and the torsional vibration of satellite solar panels. Herein, ACX proposes to address this problem by developing a surface mount piezoceramics actuator for torsional control. Target applications will be selected which have military and commercial significance. Devices will be designed, built and tested to demonstrate their ability to meet the functional requirements of the target applications. Performance prediction tools will be developed for design purposes.