Noncontact Measurement Techniques for Model Correlation

There are a variety of different noncontacting measurements that can typically be employed for developing modal test data. Digital image correlation, dynamic photogrammetry, and three dimensional (3D) laser vibrometry are all noncontacting measuring approaches that were used to obtain modal data for a candidate test structure along with traditional accelerometer measurements. Each approach has its benefits and drawbacks, so comparative measurements are made using these devices to show some of the strengths and weaknesses of each technique. Comparisons are made in all cases to a well-studied, finite-element model as well as to each other.