INCLUDING CAMERA-BASED MEASUREMENTS IN FREQUENCY-BASED SUBSTRUCTURING

Dynamic Substructuring make it possible to obtain structures behavior starting from model of their parts. The purpose of this study is to analyze a new methodology for Experimental Dynamic Substructuring to experimentally model a structure by using High Speed Camera (HSC) measurements. Experimental substructuring can be performed in different ways, but this thesis focuses on frequency based substructuring (FBS) and in finding an appropriate way to include photogrammetric data (camera measurements) to couple substructures. Starting from experimental camera and accelerometers measurements performed on two substructures excited by hammer impacts, the idea of this thesis is to use information of a high number of points, combined with accelerometers information through a mixing method (System Equivalent Model Mixing) to overcome the noise that arise in the raw camera data. High speed cameras generate a new opportunity for substructuring, because each pixel can be seen as an independent sensor, so camera measurements provide a full field representation of the interfaces. The aim of this work is to elaborate this huge amount of data, to post process and combine them with neat accelerometers data through a software code, in order to get a more accurate frequency response functions (FRF) to enhance substructures coupling. A comparison between experimental results obtained by this new approach and a numerical coupling will show how High-Speed Camera measurement can be efficiently included in the methodology of Frequency based substructuring.