Damage identification in structural health monitoring: a brief review from its implementation to the Use of data-driven applications

The damage identification process provides relevant information about the current state of a structure under inspection, and it can be approached from two different points of view. The first approach uses data-driven algorithms, which are usually associated with the collection of data using sensors. Data are subsequently processed and analyzed. The second approach uses models to analyze information about the structure. In the latter case, the overall performance of the approach is associated with the accuracy of the model and the information that is used to define it. Although both approaches are widely used, data-driven algorithms are preferred in most cases because they afford the ability to analyze data acquired from sensors and to provide a real-time solution for decision making; however, these approaches involve high-performance processors due to the high computational cost. As a contribution to the researchers working with data-driven algorithms and applications, this work presents a brief review of data-driven algorithms for damage identification in structural health-monitoring applications. This review covers damage detection, localization, classification, extension, and prognosis, as well as the development of smart structures. The literature is systematically reviewed according to the natural steps of a structural health-monitoring system. This review also includes information on the types of sensors used as well as on the development of data-driven algorithms for damage identification.Peer ReviewedPostprint (published version

Creation of an Experimental Engineering Toolbox for the Digital Transformation of Manual Jet Engine Assembly

The fast and safe motion of goods and people is one of the foundations of the modern world. Jet aircraft is the fastest transport at the moment along with high-speed trains. Accordingly, both production and maintenance of aircrafts are an important task of our modern industrial environment as well. Modern aircraft engines require appropriate care and understanding of design and manufacturing. This is even more important, as the production of aerospace engines remains a manual process in many cases with limited data sources. Thus, quality control will need to take into account verification of manufacturing and assembly steps through specific checks and controls whilst implementing additional data sources. Automation of tasks still is at a low level. In this article a review of the challenges with regard to controls, automation and process and technical understanding for aerospace engine production and repair is provided. As this requires the collaboration of many teams and partners, an improvement and step change towards deeper understanding and process efficiency is required. As many operations remain manual, innovations for how humans interact with the technology and collaborate with an industrial environment are needed. The project in this article demonstrates the creation and usage of the proposed solutions for collaboration, troubleshooting and error correction

Smart augmented reality instructional system for mechanical assembly

Quality and efficiency are pivotal indicators of a manufacturing company. Many companies are suffering from shortage of experienced workers across the production line to perform complex assembly tasks such as assembly of an aircraft engine. This could lead to a significant financial loss. In order to further reduce time and error in an assembly, a smart system consisting of multi-modal Augmented Reality (AR) instructions with the support of a deep learning network for tool detection is introduced. The multi-modal smart AR is designed to provide on-site information including various visual renderings with a fine-tuned Region-based Convolutional Neural Network, which is trained on a synthetic tool dataset. The dataset is generated using CAD models of tools augmented onto a 2D scene without the need of manually preparing real tool images. By implementing the system to mechanical assembly of a CNC carving machine, the result has shown that the system is not only able to correctly classify and localize the physical tools but also enables workers to successfully complete the given assembly tasks. With the proposed approaches, an efficiently customizable smart AR instructional system capable of sensing, characterizing the requirements, and enhancing worker\u27s performance effectively has been built and demonstrated --Abstract, page iii

Shuttle Ground Operations Efficiencies/Technologies (SGOE/T) study. Volume 2: Ground Operations evaluation

The Ground Operations Evaluation describes the breath and depth of the various study elements selected as a result of an operational analysis conducted during the early part of the study. Analysis techniques used for the evaluation are described in detail. Elements selected for further evaluation are identified; the results of the analysis documented; and a follow-on course of action recommended. The background and rationale for developing recommendations for the current Shuttle or for future programs is presented

An evaluation of the Microsoft HoloLens for a manufacturing-guided assembly task

Many studies have confirmed the benefits of using Augmented Reality (AR) work instructions over traditional digital or paper instructions, but few have compared the effects of different AR hardware for complex assembly tasks. For this research, previously published data using Desktop Model Based Instructions (MBI), Tablet MBI, and Tablet AR instructions were compared to new assembly data collected using AR instructions on the Microsoft HoloLens Head Mounted Display (HMD). Participants completed a mock wing assembly task, and measures like completion time, error count, Net Promoter Score, and qualitative feedback were recorded. The HoloLens condition yielded faster completion times than all other conditions. HoloLens users also had lower error rates than those who used the non-AR conditions. Despite the performance benefits of the HoloLens AR instructions, users of this condition reported lower net promoter scores than users of the Tablet AR instructions. The qualitative data showed that some users thought the HoloLens device was uncomfortable and that the tracking was not always exact. Although the user feedback favored the Tablet AR condition, the HoloLens condition resulted in significantly faster assembly times. As a result, it is recommended to use the HoloLens for complex guided assembly instructions with minor changes, such as allowing the user to toggle the AR instructions on and off at will. The results of this paper can help manufacturing stakeholders better understand the benefits of different AR technology for manual assembly tasks

A review of impact damage detection in structures using strain data

This paper aims to provide a state-of-the-art review on impact damage detection techniques in structures using strain data. An overview of impact detection systems is provided. These include sensors, specimens, and impact sources used for developing and testing strategies. The review is focused on approaches that use impact strain data (passive approach) to determine simultaneously the location and/or energy of an impact at the time it occurs. These approaches can be classed into two main groups, one based on analytical models and the other based on data-driven models. The former uses a first-principle model obtained from physical laws, whereas the latter describes complex relationships between input and output data obtained by experiments or simulations. Although some weaknesses and strengths are cited, we did not attempt to compare these approaches, and we do not comment the quantitative results.Peer ReviewedPostprint (author's final draft

The Public Service Media and Public Service Internet Manifesto

This book presents the collectively authored Public Service Media and Public Service Internet Manifesto and accompanying materials.The Internet and the media landscape are broken. The dominant commercial Internet platforms endanger democracy. They have created a communications landscape overwhelmed by surveillance, advertising, fake news, hate speech, conspiracy theories, and algorithmic politics. Commercial Internet platforms have harmed citizens, users, everyday life, and society. Democracy and digital democracy require Public Service Media. A democracy-enhancing Internet requires Public Service Media becoming Public Service Internet platforms – an Internet of the public, by the public, and for the public; an Internet that advances instead of threatens democracy and the public sphere. The Public Service Internet is based on Internet platforms operated by a variety of Public Service Media, taking the public service remit into the digital age. The Public Service Internet provides opportunities for public debate, participation, and the advancement of social cohesion. Accompanying the Manifesto are materials that informed its creation: Christian Fuchs’ report of the results of the Public Service Media/Internet Survey, the written version of Graham Murdock’s online talk on public service media today, and a summary of an ecomitee.com discussion of the Manifesto’s foundations