Design and analysis of supporting structure with smart struts for active vibration isolation

This research investigates a supporting structure with smart struts under crude vibration, in the aspect of their modeling and analysis. Particularly, in case of most rotorcrafts, structure-borne noise and vibration transmitted from the gearbox contains multiple spectral elements and higher frequencies, which include gear mesh frequencies and their side bands. In order to manage this issue, many research efforts have devoted to active smart struts which have tunable stiffness such that higher level of attenuation is possible. However, present techniques on the active control are restricted mostly to the control of a single or multiple sinusoids and thus these are not applicable to manage modulated and multi-spectral signals. Therefore, enhanced control algorithms are required in order to achieve simultaneous attenuation of gear mesh frequencies and their side bands. Proposed algorithms are employing two nonlinear methods and one model-based technique. Their performances are verified by comparing with conventional algorithms. Moreover, these algorithms are implemented to exhibit whether they are feasible to narrowband or broadband control through experiments with a single smart strut. Novel methodologies are expected to be applied to several active vibration and noise control practices such as vehicles and other engineering structures.