Accurate structural excitation through adaptive control

Kurzfassung

In order to study the phenomena that surrounds structure-borne noise mechanisms, it is necessary to have complete control over the structural excitation source, or equivalently, control over the forces injected into a structure. In other words, it is necessary to accurately reproduce operational forces on the structure under study. The control over the excitation source is usually managed simply by defining a desired input signal with a particular amplitude or frequency profile. However, this approach is rather incomplete since the profile defined does not take into account the modifications resulting from the interaction between source and structure. If the idea is to inject into the structure an exact copy of a reference force signal, an active controller can be used prior to the amplification stage in order to adjust amplitude and phase to obtain such copy of the reference force at the injection point on the structure. The following work describes the adaptive controller implemented for such an objective and discusses test results obtained in the laboratory.