Analysis of typical surface defects of aluminum aircraft fuselage using a non-destructive inspection and measurement system based on structured light

The work is part of the research activities performed within the framework of the “Nemesi- New Engineering & Manufacturing Enhanced System Innovation” research and development program. The aim of the research is to evaluate the accuracy and measurement uncertainty characterizing the entire process of the digitized acquisition, scanning and measurement of surface defects on aluminum aircraft fuselage. Additionally, it aims to determine the combinations of the main process parameters that make it less sensitive, and therefore robust, to the effect of disturbing factors, such as technological imperfection and environmental variations. Special attention was put on the study of two specific types of aircraft surface defects: scratches and depressions (dents). For scratches, three different morphological configurations were studied: linear, crossed, and curved scratches. Reference depth measurement of the defects was obtained by using a digital depth micrometer (comparator), an instrument currently certified in the aeronautical field. These values were compared with the outputs measured using the 3D scanner system Atos Q – Zeiss and the related analysis software Gom Inspect Pro. The analysis of the results showed very accurate and reliable defect depth values when compared with the reference depth values obtained from the certified digital micrometer/comparator. Future developments of this research will focus on expanding the range of the analysed defect types, including further surface anomalies and complexities, as well as several materials. With regards to future trends, the integration of machine learning algorithms to enhance the predictive capabilities of defect detection and measurement processes will also be explored.