Holographic Interferometry has been successfully employed to characterize the materials and behavior of diverse types of structures under stress. Specialized variations of this technology have also been applied to define dynamic structural behavior. Such applications of holographic techniques offer some of the most effective methods of structural analysis and flaw identification available. This technology is nondestructive, real-time, and definitive in allowing the identification of structural and mechanical geometry as well as describing dynamic behavior under stress. Structures and materials can be analyzed with very low amplitude stress or excitation and the resultant data can be used to adjust the accuracy of mathematically derived structural models or as criteria for complete inspection and analysis programs, as well as in developmental analysis.
Holographic Interferometry consequently offers a powerful tool to aid in the development and primary engineering analysis and development of advanced structures ranging from miniature to massive. Small, high precision structures in particular require ever increasingly accurate methods of dynamic structural and vibration characterization. Significant examples include advanced automotive, aerodynamic, undersea, and other highly mobile platforms in applications that must consider environments where extremes in vibration, mechanical, and thermal stresses can affect both operation and structural stability. These are ideal requisites for analysis using advanced holographic methods in the initial design and subsequent test of miniature components and structures for a braod range of applications. Advanced real-time and time-average holographic methods allow the identification and characterization of motion geometries, minute displacements, structural behavior, and defects. Such information is often crucial to the determination of mechanical configurations and designs as well as operational parameters of these structural components. The ability to couple real-world hologrpahic information with Finite Element Analysis models allows a complete validation of modeling and verification of operational parameters.
Advanced Holographic techniques were applied to characterize the behavior and structure of a series of different complex experimental mechanical structures in their operational configurations. It was determined that such information was of great value since the thin metal assembly would be subjected to vibrational stress in normal use. The goal was to determine if dynamic vibration behavior and structural characteristics, as well as certain flaws and anomalies could be identified. The method employed depends on introducing low level, nondestructive vibration and stress which propagate to induce corresponding resonances and minute displacements at the surface of the component.