A Brief History of Vibration Testing and Analysis for Industry: 1959 to 2019 and Beyond
This lecture consists of two parts – one looking back and the other looking forward – addressing the specific issue of how to use vibration tests together with computer analysis to manage the many structural dynamics problems which affect engineering structures of all types. In the early days, theoretical modelling and numerical predictions were really quite basic and much reliance was put on whatever measurements could be made of the various vibration phenomena encountered in industrial practice. The growth of computer power from the late 1960s led to significant enhancement in prediction capabilities, but never succeeded in making tests redundant (as some had predicted). To this day, tests remain as essential tools to ensure that computer models are good enough to use for design.
By the time of the millennium, the two disciplines – Analysis and Test – coexisted as more or less equal partners. Now, twenty years on, we find that it is standard practice to use modal tests to validate the mathematical models of individual structural components and assemblies before these can be used for design optimisation. On the other ‘side’, we find increasingly that we need to use our advanced computer models to design the endurance or qualification tests that must be carried out to demonstrate the fitness for purpose of finished products before they can be safely put into service. These certification tests constitute the final verification of the product itself. Today we are moving into a future where the two main technologies are fully integrated, to a Fusion of Test and Analysis. The talk explains why and illustrate how such an evolution provides an optimum capability for the Structural Dynamicist of today, and the immediate future: by developing a technology where the output of the integrated parts is greater than the sum of the individual contributions.
David J. Ewins, PhD., FRE, FREng
Distinguished Research Fellow
Imperial College London, UK
David Ewins studied at Imperial College London and at Cambridge University. He was based at Imperial throughout his career, as Professor of Vibration Engineering since 1983, working in collaboration with Rolls-Royce for over 50 years. He also spent 8 years part-time at Bristol University and has been Visiting Professor in the USA, France, Switzerland and Singapore. He is a Fellow of the Royal Society, the Royal Academy of Engineering in the UK and the Society of Experimental Mechanics in the USA. He received the 2015 ASME Jacob P Den Hartog Award for lifetime achievements in Vibration Engineering. He has consulted for a wide range of industries world-wide, including Rolls-Royce and MOD in the UK, Boeing, Mercedes Benz, Bosch and Ford and most recently he has joined the ESC group at NASA. Recently, he was Chairman of the Scientific and Technological Advisory Board of the EU Clean SKY €2bn programme. He is the author of the text Modal Testing: Theory Practice and Application, first published in 1984, and has presented some 150 short courses world-wide, including the first Modal Testing course presented by Vibration Institute in 1983.
The Vibration Institute
Vibration analysis and machine condition monitoring training and certification
The mission of the Vibration Institute is to disseminate practical information on evaluating machinery behavior and condition without commercial interest. The Institute offers programs including education, training, certification, and opportunities for exchanging technical knowledge, information, procedures, and data that are offered through meetings, publications, formal training and networking.