Local coupling between actuator and sensor pairs in light honeycomb structures

This paper considers the local dynamic coupling between closely spaced actuator-sensor pairs mounted on a light honeycomb structure, with an accelerometer as a sensor and either force or piezoceramic actuator. This initial work is carried out on a resiliently mounted honeycomb beam structure and it is found that the compliance of the honeycomb core significantly affects the coupling if the actuator and sensor are closely located on opposite sides of the beam. The experimentally observed local dynamic coupling is modelled by a single-degree-of-freedom mass-spring-damper system. The effect of this coupling on the stability and performance of a direct velocity feedback control system is examined, and is shown to provide an inherently stabilising mechanism when using a piezoceramic actuator.