Experimentally Tuned Airframe Hybrid Stick Model Employing Digital Image Correlation for Ground Vibration Testing

This research presents a new experimentally tuned reduced-order modeling methodology employing a hybrid stick model representation. Digital image correlation (DIC) is used to synthesize mode shapes within a frequency range of interest during Ground Vibration Testing (GVT). Experimental mode shapesare augmented into the Guyan Reduced Order Model (ROM) to develop a corresponding Craig-Bampton ROM. The latter is used to compute residual mass and stiffness matrices to supplement a traditional stick model developed through a unitary loading method; this accounts for the dynamic imparity between the stick model and the global finite element model as the simplified stick model generally ignores degree of freedom coupling. The new method proposes retaining the handling flexibilities of the conventional stick model while adding experimental dynamic accuracy of the matrix-based Craig-Bampton condensation technique in conjunction with the full-field vibration characteristics. A case study is proposed to evaluate the dynamic fidelity of an experimentally tuned hybrid stick model where the modal fidelity of the proposed hybrid stick model is compared against that of the experimental model.

Jackson Reid
Faculty Supervisor: 
Mostafa El Sayed
Partner University: