In this research, the modal parameters of a beam in free-free condition are extracted by performing different experiments in laboratory. For this purpose, two different techniques are employed. The first methodology is considered as a time domain method in Operational Modal Analysis. While the other one is frequency domain impact hammer test which is categorized as an Experimental Modal Analysi...

AbstrAct: The Operational Modal Analysis technique is a methodology very often applied for the identification of dynamic systems when the input signal is unknown. The applied methodology is based on a technique to estimate the Frequency Response Functions and extract the modal parameters using only the structural dynamic response data, without assuming the knowledge of the excitation forces. Su...

ABSTRACT This work presents the experimental evaluation of the state-variable modal decomposition (SVMD) method for modal parameter estimation of multi-degree-of-freedom and continuous vibration systems. Using output response ensembles only, the generalized eigenvalue problem is formed to estimate eigen frequencies and modal vectors for a lightly damped linear clamped-free thin experimental bea...

Am ajor problem ofe-commerce is the high rate of customer initiated abortions of processes. It may be solved by the implementation of a Push System that supports the webshop. One major module of the Push System is the Pushflow Manager that proactively l eads customers through their processes by taking over tasks or triggering following activities. Its theoretical background, the Push Concepts, ...

In this paper, a computationally simple approach for damage localization and quantification in beam-like structures is proposed. This method is based on using modal flexibility curvature (MFC) and particle swarm optimization (PSO) algorithm. Analytical studies in the literature have shown that changes in the modal flexibility curvature can be considered as a sensitive and suitable criterion for...

In this work we present a study of the characterization of an Advanced Combat Helmet (ACH) using experimental modal analysis techniques. A medium-sized helmet was impacted at different location and the vibration response was used to estimate a global frequency model. This was achieved using the modal parameters of the local models obtained for a specific input-output location and combining them...

Iterative learning control applies to systems that repeatedly execute the same finite duration task. The distinguishing feature of this form action is all data generated on a previous execution task available compute for subsequent execution. This paper uses repetitive process stability analysis and optimization techniques design dynamic controller that, in contrast designs process/2D setting, ...

The problem of structural model identification under both known and unknown input excitations, is addressed. In-flight data analysis is an important instance of that problem. Input/output and output-only eigenstructure identification methods are described and compared, within two classes of methods: subspace-based and prediction error. In particular, different types of relevant projections for ...

Modal parameter estimation in terms of natural frequencies and mode shapes is studied using smooth orthogonal decomposition for randomly excited vibration systems. This work shows that under certain conditions, the smooth orthogonal decomposition eigenvalue problem formulated from white noise induced response data can be tied to the unforced structural eigenvalue problem, and thus can be used f...

Driven by the need to reduce the installation cost and maintenance cost of structural health monitoring (SHM) systems, wireless sensor networks (WSNs) are becoming increasingly popular. Perfect time synchronization amongst the wireless sensors is a key factor enabling the use of low-cost, low-power WSNs for structural health monitoring applications based on output-only modal analysis of structu...