Closed‐loop experimental testing framework for structural control applications

Abstract

Within civil engineering, the inclusion of control strategies is confined to limited application areas due to the practical overhead and an alleged conservatism. This paper presents a simple yet flexible framework for experimental testing of closed‐loop structural systems. Compared to alternative existing solutions, the proposed framework requires limited programming knowledge, which heavily simplifies the implementation for the operator and thus reduces the associated practical overhead. The feasibility of the framework is demonstrated through two experimental case studies in which control strategies are used to, respectively, design and implement a hybrid tuned mass damper (TMD) and conduct closed‐loop model updating. The case studies exemplify the diversity of control applications within civil engineering, and it is noted that while hybrid TMDs are used in the civil engineering industry, limited experimental application studies exist on closed‐loop model updating of structural systems. It is concluded that the presented framework can be applied to cover a variety of structural control applications within civil engineering and the successful implementation of the framework in the two case studies highlights the benefits of feedback control within these applications.

Perturbation-invariant eigenvalue assignment for statistical damage localization

“…A problem in vibration-based damage localization is that the identifiable vibration features carry insufficient information on damage to provide the required level of robustness [1,2]. In the attempt to resolve the robustness problem, different feedback strategies have been adopted from control engineering [3]. The strategies are typically based on eigenstructure assignment, which allows for designing closed-loop eigenspectra and eigenspaces in accordance with some predefined objective [4,5].…”

“…The practical feasibility of the feedback strategies has been somewhat hindered by the hardware requirements [3]. This roadblock has, however, been mitigated by the introduction of a virtual implementation, in which the feedback is realized by offline processing of open-loop input-output data [11].…”

Eigenvector Assignement for Damage Localization With Invariant Eigenvalues

“…A commonly encountered challenge in vibration-based damage localization is that the identifiable vibration features carry insufficient information on damage to provide the required level of robustness [1,2]. In the attempt to resolve the robustness problem, different feedback strategies have been adopted from control engineering [3]. These strategies are typically based on eigenstructure assignment, which allows for designing closed-loop (CL) system eigenvalues and Dahl, Ulriksen, and Nielsen eigenvectors in accordance with some predefined objective [4,5].…”

“…The practical feasibility of the feedback strategies has been hindered by the required availability of appropriate hardware [3]. This roadblock has, however, been mitigated by the introduction of a virtual implementation, where the feedback is realized by offline processing of open-loop (OL) input-output data [11].…”