The Integrated Test Analysis Process for Structural Dynamic Systems

Over the past 60 years, the U.S. aerospace community has developed, refined, and standardized an integrated approach to structural dynamic model verification and validation.

One name for this overall approach is the Integrated Test Analysis Process (ITAP) for structural dynamic systems. ITAP consists of seven sequential tasks, namely: (1) definition of test article finite element models; (2) systematic modal test planning; (3) measured data acquisition; (4) measured data analysis; (5) experimental modal analysis; (6) systematic test-analysis correlation; and (7) reconciliation of finite element models and modal test data. Steps 1, 2, and 7 rely strictly on mathematical model disciplines, and steps 3 and 4 rely on laboratory disciplines and techniques. Current industry practice of steps 5 and 6 calls for interaction of mathematical model and laboratory disciplines, which compromises the objectivity of both modeling and laboratory disciplines. This book addresses technical content, strategies, and key relevant experiences related to all steps of ITAP, except for measured data acquisition which is the specialized domain of highly experienced laboratory professionals who contend with mechanical and electrical practicalities of instrumentation, excitation hardware, and data collection systems.

Robert N. Coppolino received his formal education in New York City having graduated from Stuyvesant High School and earned a B.S. Aerospace Engineering, and an M.S. and Ph.D. in Applied Mechanics at the Polytechnic Institute of Brooklyn. As a structural dynamics engineer at Grumman Aerospace Corporation (1967-1975), he supported the Lunar Module, Skylab, and Space Shuttle programs, and contributed to development of techniques for launch vehicle pogo (instability) suppression and propellant tank hydroelastic modeling and test-analysis correlation. From 1975-1983, Dr. Coppolino was at The Aerospace Corporation, ultimately holding the post of manager of the Engineering Dynamics Section. While at Aerospace, he supported NASA's Space Shuttle Pogo Integration Panel, developed the Simultaneous Frequency Domain (SFD) method for experimental modal analysis, and defined innovative residual vector techniques the were successfully employed in Space Shuttle nonlinear payload interface flight loads predictions and detection of structural damage on offshore jacket platforms. From 1983-1987, he served as manager of the Advanced Methods and Development branch at the MacNeal-Schwendler Corporation (MSC). During his stay at MSC he led a consortium composed of MSC, the J. S. Bendat Company, and Synergistic Technology Incorporated, which developed technologies that were ultimately called the Integrated Test Analysis Process (ITAP). From 1987 to the present, Dr. Coppolino has held various senior posts at Measurement Analysis Corporation, currently serving as Chief Technology Officer for Torrance Operations. During this period he collaborated closely with the late Julius S. Bendat on development of nonlinear spectral techniques for identification of nonlinear systems. In addition, Dr. Coppolino continued development of ITAP components including efficient procedures for modal test-analysis reconciliation. The full suite of ITAP capabilities experienced its first end-to-end, "prime-time" application on the International Space Station P5 Short Spacer modal test, conducted at NASA/MSFC in 2001.