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Full-Text Articles in Engineering
Quality Assurance Of Lightweight Structures Via Phase-Based Motion Estimation, Ikenna E. Ifekaonwu
Quality Assurance Of Lightweight Structures Via Phase-Based Motion Estimation, Ikenna E. Ifekaonwu
Electronic Theses and Dissertations
In recent years, lightweight structures have become mature and adopted in various applications. The importance of quality assurance cannot be overemphasized hence extensive research has been conducted to assess the quality of lightweight structures. This study investigates a novel process that exploits motion magnification to investigate the damage characteristics of lightweight mission-critical parts. The goal is to assure the structural integrity of 3D printed structures and composite structures by determining the inherent defects present in the part by exploiting their vibration characteristics. The minuscule vibration of the structure was recorded with the aid of a high-speed digital camera, and the …
An Enhanced Fuselage Ultrasound Inspection Approach For Ishm Purposes, Francisco Ospina
An Enhanced Fuselage Ultrasound Inspection Approach For Ishm Purposes, Francisco Ospina
Theses and Dissertations
This effort constitutes a systems engineering approach in which the materials science, ultrasound structural health monitoring, flight and maintenance operations, and relevant aeronautical policies and programs are involved to explore the evolution and characterization of structural cracks in aircraft fuselage structures in which the loads are varying. During flight, an aircraft fuselage skin and structure are subjected to varied cyclic loads, which can cause embedded cracks and other damage features to change their characteristics due to loading effects. The current research is based in the application of finite element modeling techniques using COMSOL and PZFLEX software to characterize the behavior …
Damage Detection Via Structural Model Updating Using Frequency Response Functions And Genetic Algorithms, Bassam Sabry Fawzy Elsaid
Damage Detection Via Structural Model Updating Using Frequency Response Functions And Genetic Algorithms, Bassam Sabry Fawzy Elsaid
Archived Theses and Dissertations
This thesis covers the development of a model updating technique which relies on the introduction of correction factors to the elemental stiffness matrix of a beam Finite Element Model (FEM). A Genetic Algorithm selects the values of correction factors by minimizing the difference between an experimentally measured Frequency Response Function (FRF) and the FRF calculated from the FEM being updated. The model updating technique was employed as a damage detection algorithm. The first phase of damage detection is to use model updating to eliminate experimental and modeling errors between the FRF of a beam measured experimentally and the FRF of …