Ground Vibration Testing (GVT) Master Class US

A ground vibration test (GVT) is an experimental modal analysis (EMA) test performed on an aircraft. It confirms the validity of dynamic modeling of new and modified aircraft, and is required for certification.  This 2-day class will cover in detail the challenges and modern solutions for GVT testing of full aircraft structures.  An integrated approach to handle the test preparation, data acquisition, modal parameter estimation, model correlation, updating, and exploitation will be demonstrated

The seminar will focus on practical implementation, combining classroom lectures with an actual ground vibration test of the world’s first all-metal airplane: the Museum of Flight’s Boeing 247, introduced in 1933.

Course attendees will be introduced to the theoretical background, digital signal processing, excitation techniques and extraction of modal parameters from measured frequency response functions. Single degree of freedom relationships Multiple degree of freedom relationships Multiple Input/Output Testing Poles and residues Digital Signal Processing for Experimental Modal Analysis Sampling and Quantization, Aliasing, Leakage, Windowing Excitation Techniques Frequency Response Function Estimators, Coherence Functions Measurement Examples (Good vs. Bad) Mode indicator functions Stabilization Diagrams, Modal Parameter Estimation, PolyMAX Non-linear behavior Modal Validation

Attendees will participate in an actual GVT test at the Museum of Flight Restoration Center

• Test preparation and de-risking
• Instrumentation of the aircraft
• Measurement set up validation
• Phase separation techniques (random, stepped, swept sine excitations)
• Phase resonance techniques (normal modes testing)
• Modal parameter estimation
• Computer model animation of the structural modes of vibration
• Finite element correlation and updating

What will the attendee learn
This training is intended for managers and engineers involved in dynamic testing of aircraft structures. The value of a hybrid Test/CAE technology that enables high interaction between test and analysis organizations will be demonstrated.

• Experience the value of the hybrid Test/CAE technology that enables high interaction between test and simulation departments.
• Increase efficiency in identifying modal parameters of vibrating structures
• Learn  how to accelerate the correlation and updating of parameters using modal test data.