In the era of Industry 4.0, with the availability of production data, there is an increasing demand to detect the throughput bottleneck in manufacturingsystems using a datadriven approach. Traditional data-driven app...
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ISBN:
(纸本)9798350358513;9798350358520
In the era of Industry 4.0, with the availability of production data, there is an increasing demand to detect the throughput bottleneck in manufacturingsystems using a datadriven approach. Traditional data-driven approaches identify the bottleneck indirectly by analyzing machine metrics collected from the shop floor, such as machine starvation and blockage. While efficient in most cases, these approaches often fail to identify the bottleneck according to its sensitivity-based definition, potentially resulting in incorrect results. To address this gap, we propose a novel data-driven approach named "Bottleneck Mining". This approach utilizes event logs as inputs to derive executable simulation models through process mining. Subsequently, it performs sensitivity analysis on the system throughput to accurately locate the bottleneck. The usefulness of the proposed approach has been demonstrated on several production lines.
The assembly process, a pivotal phase in manufacturing, involves the integration of individual components into a finished product. The limited flexibility of the product line often leads to repeated design production,...
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ISBN:
(纸本)9798350387568;9798350387575
The assembly process, a pivotal phase in manufacturing, involves the integration of individual components into a finished product. The limited flexibility of the product line often leads to repeated design production, a practice that imposes substantial costs on companies. Concurrently, a diverse array of data and knowledge must be conveyed within this environment to enable various tools to collaborate towards achieving the desired result. For instance, design data is serialized in a step file, while analysis tools present their findings or extract knowledge in a different format (e.g., graph). To curtail product line expenses and establish a user-friendly interface with all aspects of an assembly system, this paper introduces a knowledge base-a repository for storing raw data and extracted knowledge-to bridge design and analysis tools. The proposed knowledge base, developed using model-driven engineering techniques, tackles the primary challenge of mapping and transferring data among disparate sources. The effectiveness of the knowledge base is assessed using case studies from industrial partners in the AssistedDfA project.
There has been a shift to mass customisation production for most of the manufacturingsystems in recent decades. This leads to the need of predicting workers' performance for task assignments for all the main step...
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Collaborative manufacturing is central to agile, intelligent, and cloud-based manufacturing paradigms. This paper presents the design and implementation of a web-based collaborative manufacturing system based on a kno...
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Modern Ontology-Based engineering (OBE) systems, built over the foundations of knowledge-Based engineering (KBE), leverage ontology-based technologies and the semantic web to capture and formalise knowledge holistical...
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ISBN:
(纸本)9783031807749;9783031807756
Modern Ontology-Based engineering (OBE) systems, built over the foundations of knowledge-Based engineering (KBE), leverage ontology-based technologies and the semantic web to capture and formalise knowledge holistically. This comprehensive knowledge repository can subsequently feed design and decision support tools with robust generative features. However, the integration and reuse of knowledge poses challenges for which it is necessary to develop appropriate methods and tools capable of handling diverse types of knowledge from both human experience and databases. The objective of this paper is to discuss the current limitations of OBE systems to address knowledge integration and reuse, based on the research and experiences of the authors in the aerospace manufacturing industry. This aims to provide a set of Research Questions (RQ) and the author's position to them, to serve as future research work and topics of discussion for the scientific community.
On the path towards more complex systems that deliver more value at lower cost in semiconductor products, the industry had to develop frameworks to support the rapid design of very complex systems giving rise to wides...
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ISBN:
(纸本)9798350387186;9798350387179
On the path towards more complex systems that deliver more value at lower cost in semiconductor products, the industry had to develop frameworks to support the rapid design of very complex systems giving rise to widespread adoption of VLSI. A very similar situation exists for the advanced manufacturing process supporting the semiconductor industry. In order to keep the pace of innovation in manufacturing technology, the concept of a Digital Twin has been the main target of multiple studies and proposals. In this work we demonstrate that by learning from the lessons of VLSI, we aim to construct a digital twin of the manufacturing process that permits the monitoring and optimization of the most important aspects of semiconductor manufacturing, while at the same time demonstrating that such agnostic approach can also be applied to other manufacturing operations. A key component to the digital twin is the creation and deployment of reliable, experimentally verified machine learning models. In this work we will present necessary model characteristics to meet such requirements, under data conditions that are atypical for traditional machine learning training methods.
Powder bed fusion (PBF) is an emerging metal additive manufacturing (AM) technology that enables rapid fabrication of complex geometries. However, defects such as pores and balling may occur and lead to structural unc...
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ISBN:
(纸本)9798350358513;9798350358520
Powder bed fusion (PBF) is an emerging metal additive manufacturing (AM) technology that enables rapid fabrication of complex geometries. However, defects such as pores and balling may occur and lead to structural unconformities, thus compromising the mechanical performance of the part. This has become a critical challenge for quality assurance as the nature of some defects is stochastic during the process and invisible from the exterior. To address this issue, digital twin (DT) using machine learning (ML)-based modeling can be deployed for AM process monitoring and control. Melt pool is one of the most commonly observed physical phenomena for process monitoring, usually by high-speed cameras. Once labeled and preprocessed, the melt pool images are used to train ML-based models for DT applications such as process anomaly detection and print quality evaluation. Nonetheless, the reusability of DTs is restricted due to the wide variability of AM settings, including AM machines and monitoring instruments. The performance of the ML models trained using the dataset collected from one setting is usually compromised when applied to other settings. This paper proposes a knowledge transfer pipeline between different AM settings to enhance the reusability of AM DTs. The source and target datasets are collected from the National Institute of Standards and Technology and National Cheng Kung University with different cameras, materials, AM machines, and process parameters. The proposed pipeline consists of four steps: data preprocessing, data augmentation, domain alignment, and decision alignment. Compared with the model trained only using the source dataset, this pipeline increased the melt pool anomaly detection accuracy by 31% without any labeled training data from the target dataset.
In order to enhance the quality of customized furniture panel processing, avoid information silos between workstations, and promote intelligent manufacturing in customized furniture enterprises, this study constructs ...
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manufacturing key metrics are a useful approach for evaluating shop floor operations. The collaboration between operators and robots is essential in maintaining a resilient performance within smart and flexible manufa...
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manufacturing key metrics are a useful approach for evaluating shop floor operations. The collaboration between operators and robots is essential in maintaining a resilient performance within smart and flexible manufacturingsystems. For effective collaboration, both operators and robots must possess varying degrees of resilience, including full resilience, partial resilience and the ability to handle total disruptions. In this paper, lead time is considered a significant key metric. When the system is fully resilient and dependable, it achieves the optimal lead time. Consequently, lead time serves as a benchmark for evaluating the system's performance. However, if the robot experiences significant performance issues, it can negatively impact the cycle time, resulting in longer lead times. The discrepancy between the optimal lead time and the lead time obtained during partial or complete disruption is subtracted from the optimal lead time. To ensure the validity of the findings, mathematical equations are utilized in combination with other relevant data. This approach contributes to the knowledge base in the field. Finally, the paper will provide suggestions for future research endeavors..
Due to the complexity of robot-like systems (RLS), new developments are often avoided, and most variants of the systems are designed. The primary determinant of an RLS is its drivetrain, which comprises purchased comp...
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Due to the complexity of robot-like systems (RLS), new developments are often avoided, and most variants of the systems are designed. The primary determinant of an RLS is its drivetrain, which comprises purchased components, namely the controller, motor driver, motor, and gearbox. Each of these purchased parts has different interfaces that are not standardized. If the interfaces are sufficiently complex, the compatibility of the parts can no longer be guaranteed manually. Therefore, this paper presents a draft ontology that verifies the compatibility of purchased parts in RLS drivetrains. Classes and properties are obtained from expert knowledge, norms, data standards, and data sheets to build an ontology. The ontology design is evaluated using an application example for a motor-gearbox interface.
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