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A recently proposed implementation of output feedback based on signal processing eliminates the practical overhead of physical operation in closed-loop. Additionally, the ,virtual implementation facilitates realization of of multiple closed-loop systems from a single test in open loop, allows for complex gains, and removes the constraint of closed-loop stability. Care, however, must be exercised in the design of the closed-loop systems as the errors in these are governed by the intrinsic approximations in the open-loop identification. The present paper offers an examination of this item when the closed-loop systems are designed for parameter estimation in updating numerical models of structural systems. The differences between physical realization and the proposed virtual implementation are discussed, and the pivotal points outlined are demonstrated in the context of the numerical examination with a structural system.
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On the model order in parameter estimation using virtual compensators
Processing signals from open-loop system realizations can replace real-time operation using actuators in the design of closed-loop eigenstructures. One merit of the signal processing-based implementation is that it, in principle, allows virtual compensators of user-defined model order since the closed-loop systems are not to be realized during physical testing. The present paper explores the implication of the virtual compensator order in terms of the Fisher information on unknown parameters to be estimated in a model updating context. A numerical example with a structural system of engineering interest is presented that demonstrates the basic points outlined in the paper.
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- Award ID(s):
- 1634277
- PAR ID:
- 10128921
- Date Published:
- Journal Name:
- Lecture notes in mechanical engineering
- ISSN:
- 2195-4364
- Page Range / eLocation ID:
- 498-506
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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