A geometric approach to the design of remotely located vibration control systems

Over the past three decades, a wide variety of active control methods have been proposed for controlling problematic vibration. The vast majority of approaches make the implicit assumption that sensors can be located in the region where vibration attenuation is required. For many large scale structures or where the system environment is harsh, this is either not feasible or it is prohibitively expensive. As a result, the optimal control of local vibration may lead to enhancement at remote locations. Motivated by such problems in marine system environments, this paper describes a simple geometric methodology that provides an approach for defining the design freedom available for reducing vibration both at local and remote locations. The results can be used to develop design procedures for both discrete frequency and broad-band control. Robustness to modelling error can also be treated in the same geometric framework. Validation of the approach is carried out using an experimental facility that has been developed to replicate the problems associated with rotor blade vibration.