bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of product variety on work allocation and server distribution of flexible manufacturing lines
Authors: Arteaga A , Calvo R 
Published: October 2021

Abstract
Mass customization involves medium volume production of a high variety of products where flexible manufacturing systems can cope with it. The work allocation problem of assigning the work content of each workstation in a manufacturing line is formulated as the design problem of capacity allocation across the line by looking for the throughput maximization and/or simultaneous work-in-process containment or minimization. The bowl phenomenon refers to the distribution shape of work across the workstations in unpaced flow line (asynchronous flow) with buffers, experimentally observed and conjectured back in the 1960’s, but with theoretical roots not successfully established up today. The increasing value of flexible capability for mass customization makes worthy the research of the phenomenon in the presence of product variety, beyond the classical model of balanced dedicated flow lines. The three problems of workload, buffer, and server allocation are closely related, and they have been previously studied in queuing networks with metaheuristics. This paper faces the effect of product variety (service time variability) impact on the performance of the flow line, researching the bowl effect through experimental analysis. The results show a main influence of the coefficient of variation of the service times with the secondary effect of the buffer size.
An approach to Reverse Engineering Methodology for Part Reconstruction with Additive Manufacturing
Authors: López J , Vila C 
Published: October 2021

Abstract
In diverse sectors such as aerospace, transport or energy, equipment is several decades old. Due to their extended lifespan, technical and manufacturing documentation might be inaccessible or inexistent. Manufacturing process problems, wear occurring during a part life cycle, or even the unavailability of digital data (redesign of obsolete parts produced in pre-digital era, legal restriction, or trade secrecy) are some examples to outline the lack of reliable 3D data for manufacturing purposes. The manufacturing and subsequent replacement of these components can turn into a significant problem. Lack of knowledge about system’s functioning, unknown operating conditions and limited technical information hamper the design development and manufacturing of these components. Classical Reverse Engineering (RE) approaches are commonly used to facilitate the understanding of a system’s functioning and ease the design recovery to create a more accurate and suitable model for engineered components. Combining these approaches with modern digitalisation technologies and new customized fabrication techniques, such additive manufacturing, can help to reconstruct obsolete, old or legacy components lacking manufacturing data. This paper contributes with a structured method aimed to design for additive manufacturing.
Selecting software filter settings for evaluating periodic and aperiodic surface roughness
Authors: Kubátová D , Kaufnerová A 
Published: October 2021

Abstract
A lot of properties depend on the quality of the surface, such as efficiency, reliability, functional properties, external appearance, and, last but not least, the cost of the entire production process. And if there is an inaccurate assessment during evaluating the integrity of the surface, especially for assessing roughness, this can lead to fatal problems in the actual use of the inspected part in practice. In order to meet all the requirements of the evaluation of the surface structure, it is necessary to keep up with the times and always have control of new possibilities and knowledge from the fields of measuring and evaluating the integrity of the surface, and being able to implement this knowledge into real conditions of use.
In the area described in this article, the selection of software filters, this is not always the case. The main reason is low awareness and the great complexity of choosing a suitable combination of possible procedures and techniques for setting software filters.
Therefore, a comprehensive methodology for the selection of software filters for both periodic surfaces and subsequently for aperiodic surfaces was created and is described in this article. Its coherence and graphical simplicity are prerequisites for quick understanding and easy implementation of the methodology in common practice.
The methodology for the selection of the software filter has 4 steps for periodic surfaces and 5 for aperiodic surfaces, which help the user of the profilometer, whether contact or contactless, to correctly set the device. Furthermore, the methodology should ensure that two people measure the same, or at least in the order of hundredths of the same results (values), which currently is not quite the case.
Influence of different wavelet filtering reconstruction techniques applied to bidimensional surface texture characterization
Authors: Villena C , Pazos D , Andrés E M , Sanz A 
Published: October 2021

Abstract
This article develops a preliminary study of the wavelet filtering application in surface finishing, extracting two-dimensional information from the surface microgeometry in a profile. First, the key elements to be considered in the analysis are described, starting with the surface finishing process of measurement. Then, the fundamentals of wavelet-based filtering and the traditional filtration procedure is shown. This procedure eliminates the values of the detail coefficients obtained in the filtering process before the reconstruction of the signal. Other alternatives of filtration, based on the shrinkage wavelet methodology, are also considered. Next, the features of the surface finish characteristic signals are highlighted, and the alternatives considered are applied on three different profiles generated from the result of a Brinell hardness test. Finally, the main conclusions drawn from the study are presented.
Novel system for the automatization of photogrammetric data capture for metrological tasks: application to study of gears
Authors: Rodríguez M , Rodríguez P 
Published: October 2021

Abstract
This paper presents a novel methodology for the macro-photogrammetric reconstruction of gears for metrological and maintenance purposes. The process presented includes the automation of close-range photogrammetric data acquisition using a referenced platform supported by measures gathered using an Articulated Coordinate Measure Machine and the subsequent Structure for Motion processing that allows the generation of dense 3D point cloud models with metrical scale and photorealistic colour texture of the gears. On these models, it is possible to directly take measurements, extract different profiles that can be exported in 2D formats and apply advanced processes that allow the computation of roughness and curvature parameters to evaluate the wear and possible defects or pathologies.
Evaluation of the influence of post-processing on the optical inspection accuracy of additively manufactured parts
Authors: Giganto S , Martínez S , Barreiro J , Cuesta E 
Published: October 2021

Abstract
Optical measurement systems are important techniques for rapid inspecting additively manufactured parts by techniques such as selective laser melting (SLM). Depending on their application, SLM parts require post-processes such as sandblasting or heat treatment, commonly applied in order to improve their surface finish or mechanical properties, respectively. These post-processes modify the parts surface characteristics, and therefore the suitability for optical inspection. This work evaluates the influence of these SLM post-processes on optical inspection. For this, a test part, manufactured in 17-4PH stainless steel using a 3DSystems ProX100 machine, was optically measured using a structured light scanner and compared to the values obtained from contact measurements (reference values). Both optical and contact measurements were performed under three conditions: as-built, post sandblasting, and post sandblasting and subsequent heat treatment. The analysis results show that applying the sandblasting post-processing provides a surface finish to the SLM parts suitable for optical inspection. This post-process allows precise inspection of this type of parts, reaching values close to those obtained by contact. Likewise, it is concluded that the used structured blue-light scanner is suitable for inspecting SLM parts.
Feasibility analysis of using machinable glass ceramics to manufacture non-contact measurement approach metrological artefacts
Authors: Zapico P , Alvarez B J , Meana V , Telenti A , Cuesta E 
Published: October 2021

Abstract
Rather than measurement contact methods, non-contact ones are more desirable in case of on-machine and in-process measurement due to their great accessibility and high acquisition rates. Nevertheless, it is well known that these methods commonly present different issues related to the surface properties of the digitized material and other external factors. Thus, an important characterization work must be carried out by exposing each non-contact technique to different conditions. For this characterization work, the use of metrological gage artefacts is mandatory. These artefacts must be made of materials on which non-contact methods will work properly. Therefore, the analysis of new materials is still an important issue nowadays. Among the current possible materials, those that can be easily formed in typical artefact geometries stand out, while maintaining the required properties such as low thermal expansion, high hardness, etc. In this work the feasibility of a machinable glass ceramic named Macor® to produce a metrological artefact to be used with a non-contact digitizing sensor is analysed. Once stated the benefits of this material and proposed some machining conditions, an artefact is manufactured and digitized with a non-contact laser triangulation sensor, comparing its results regarding to a widely used metrological reference system.
Reference standard for the uncertainty estimation of X–ray Computed Tomography measurements of complex macro-and micro-geometries
Authors: Albajez J A , Nuño S , Díaz L C , Gallardo D , Yagüe J A , Jiménez R , Torralba M 
Published: October 2021

Abstract
Traditionally, measuring both macro and micro geometries with a single device has been challenging in metrology. Coordinate Measuring Machines (CMM) are common devices for the inspection of large features, while optical microscopes can achieve resolutions in the order of micrometers in small areas. X-Ray Computed Tomography (XCT) has become a solution not only to characterize both micro and macro geometries, but also to inspect internal features without destroying the sample. In this field, various reference standards have been developed in order to verify the capabilities of XCT systems, these artefacts include geometrical features or profiles for roughness inspection. This paper shows the design and develompent of a reference standard for XCT test which includes internal and external geometrical features and profiles for macro and micro geometrical inspection. The model is manufactured by additive manufacturing (AM), easing the process of fabrication of the artefact and allowing to test the capabilities of this technology to produce reference standards.
Determining the required cleanliness level using synthetic test contamination
Authors: Brag P , Piotter V , Plewa K , Umbach S , Herzfeldt M 
Published: October 2021

Abstract
As electrification in the automotive industry progresses, the demand is rising for test particles with specific properties. More and more new applications are also being developed, such as processes for validating cleaning steps, contamination tracking or determining cleanliness limits. This article describes how test particles can be reproducibly manufactured in all three dimensions by micro milling. In addition, it explains how the dimensional accuracy of these free-form surfaces can be analyzed with computer tomography.
Risk-based inspection planning for hydrogen technologies: review of currents standards and suggestions for modification
Authors: Ustolin F , Wan D , Alvaro A , Paltrinieri N 
Published: October 2021

Abstract
The research addressing loss of integrity (LOI) for hydrogen containment technologies requires a multidisciplinary perspective. However, lack of collaboration between materials and process safety engineers is reflected in the theory addressing the LOI phenomena. Even though the potential degrading mechanisms related to hydrogen-metals interaction are being extensively studied, they are not explicitly considered by standards and recommended practices in relation to plant inspection planning. This inevitably introduces additional uncertainties while planning for inspections and predictive maintenance and leads to the necessity to address and consider generic mechanisms of material degradation within the framework of LOI development prediction. A review of the available standards and recommended practices for inspection planning is here conducted to identify how metal-hydrogen interactions are currently considered in terms of degradation mechanisms. Focus is given to risk-based approaches, which include the assessment of potential accident scenarios as consequence of LOI. In particular, the association of metal-hydrogen mechanisms with damage factors influencing the predicted LOI frequency is studied to understand their impact both on the risk and the inspection typology. Appropriate knowledge of material degradation mechanisms for hydrogen containment is of paramount importance as it allows not only for a correct design of the equipment of interest, but also for a suitable inspection and maintenance planning so to guarantee its integrity through an effective and informed risk-based approach. A few modifications to the current standards are suggested as a result of this work.
A device to reduce positioning errors due to the machine tool compliance
Authors: Noriega A , Campa F J 
Published: October 2021

Abstract
One of the main problems that large machine tool designers must face is the onset of deflection and vibration due to the forces involved during the process: the own weight of the elements of the machine, the cutting forces and the inertial forces. The last ones are especially relevant in the case of large and heavy machine tools with cantilever elements as rams or columns. To counteract these forces, the present work proposes the use of an inertial device, based on the rotation of two eccentric mases around the same axis. Hence, a simplified dynamic model of a column is first developed, and tested during a standard face milling operation. Then, the dynamic model of the device is also developed, and a Computed Torque Control is proposed to govern the action of the device. The simulations show that the use of this device has the potential to reduce drastically the effect of the inertial forces and even the lower frequency components of the cutting forces.
Contact Image Sensor integration in Fused Filament Fabrication machines for layer inspection
Authors: Peña F , Rico J C , Valiño G , Fernández P , Meana V , Zapico P 
Published: October 2021

Abstract
One of the limiting factors for industrial application of additive manufacturing (AM) is the lack of geometrical accuracy of manufactured parts. To improve precision, non-contact sensors should be integrated into AM machines, capable of performing in-situ inspection of the part and being able to detect and compensate for the actual geometrical errors. A non-contact digitizing system is proposed in this work for the inspection of the deposited material layers, based on a Contact Image Sensor (CIS) extracted from a commercial flatbed paper scanner. In order to integrate this sensor in an AM machine, a methodology was developed that includes the sensor operation analysis, the design of the necessary hardware and software to be externally controlled and the subsequent processing of the captured images. Results prove that the CIS sensor can be integrated in any device external to the original scanner.
Finite element modelling and evaluation of mechanical properties of wood-PLA parts manufactured through Fused Filament Fabrication
Authors: Durlan J , Adrover B , Zandi M D , Lluma J , Jerez R , Travieso J A 
Published: October 2021

Abstract
Fused Filament Fabrication (FFF) is one of the most common additive manufacturing (AM) technologies that has arisen interesting from industry in a wide range of applications. In this paper, the mechanical properties of FFF 3D printed wood-PLA (Timberfill®) parts are investigated both experimentally and computationally to predict the mechanical characteristics of this material. Firstly, experimental tensile test is carried out to achieve the properties of the material. Secondly, the obtained parameters (Young’s modulus, Poisson’s ratio and yielding stress) will be use as input data in the ANSYS software to simulate a 4-point bending test. Finally, in order to validate the obtained model, the simulation results are compared to an experimental flexural test results indicating the correspondence between them. The main result of this work is an appropriate model to predict the behaviour of a 3D-printed piece formed by an internal structure with certain characteristics suitable for the manufacturing process and surrounded by a skin, which is subjected to certain external load.
Training program for researchers in design and manufacturing of experimental prototypes for fluids engineering using additive technologies
Authors: Santamaría L , García M , Gharib A , Galdo M , Blanco E , Fernández J M , Velarde S 
Published: October 2021

Abstract
Experimental testing is one of the pillars in Fluids Engineering research. The arrival of rapid prototyping, and especially, Additive Manufacturing (AM), has revolutionized this field, allowing fast and flexible prototype manufacturing. Among these technologies, Fused Deposition Modelling (FDM) allows to fabricate complex parts using light, resistant, composite materials at a very affordable cost. To harness the full potential of this technology, the fluid dynamics engineering research group (GIFD) of the University of Oviedo started a training program for researchers in this area. This rich and complete program is presented herein, emphasizing its elaborate methodology and highlighting the successful case-studies derived from its application. Knowledge and integration of this technology has granted the capability of self-manufacturing customizable, low-cost experimental prototypes with adequate mechanical properties and accuracy, which produce high-quality results. Additionally, it has widened remarkably the possibilities of experimental research, resulting in a significant increase of experimental publications.
Re-design of a component of a lower-limb robotic exoskeleton for integrating sensing capacity and enhancing multi-material direct additive manufacturing
Authors: Minguella J , Challa P R , De Los Santos M A , Lobo J , Morey P , Font J M 
Published: October 2021

Abstract
The quest for the materialisation of advanced products is expanding the need for intelligent components and devices. One of the fields of application for such products is the medical technology industry, in which many value-added products could benefit from extending its embedded functionalities. To this regard, the obtention of such products via Additive Manufacturing Technologies would be very beneficial, providing that the design requirements could be met in a seamless and direct manner. In this context, the present article develops and analyses three design iterations of a component of a lower-limb robotic exoskeleton for integrating sensing capacity on it via multi-material direct additive manufacturing. In subsequent steps, the component geometry is optimised for additive direct manufacturing, and different functionalities are incorporated (padding for comfort and circuitry for sensing). For each iteration, the design is validated by means of finite element analysis and the main manufacturing parameters are assessed to compare the different times and costs yield. The third redesign incorporates three different materials (ABS, TPU and PE+Cu), but still it is possible to be 3D printed with a two extruder-head FDM 3D printer. The design and manufacturing results obtained could be implemented in further biomedical products or other parts requiring advanced functionalities.
Product development methodology: non-quality caused in production by mistakes in product development, its measurement and improvement integration in the product development process
Authors: Gracia C , Acero R , Yagüe J A 
Published: October 2021

Abstract
A new quality focused product development (NPD) methodology, applying lean manufacturing principles and Industry 4.0 paradigms is described in this paper. This methodology has been tested in a tailor-made equipment manufacturer for the retail sector, where tight product development times are needed. This requires a high agility in the processes, meaning the overlap of phases, the integration of processes, cooperation, and automation of tasks. We have generated a system concept that collects all the manufacturing incidences related to NPD, integrated in workshops stations, creating a system that enables real time data capture and a valuable feedback loop to NPD processes. Its implementation showed an improvement over 10% in the quality of the NPD process in a period of 3 months, an increase of the productivity in both product development and manufacturing areas, and a boost of the internal customer satisfaction in manufacturing area with the product development area.
Production optimization oriented to value-added: from conceptual to a simulation case study
Authors: Pérez S , Gallego S , García M 
Published: October 2021

Abstract
Management in companies today faces a true paradigm shift, characterized by a growing optimization of global value-added structures. To pursue this goal, lean philosophy is used as it allows applying sustainable improvements to the processes of a company, focusing on the value of the process and eliminating if possible or minimizing all those activities or tasks that when executed are not beneficial, that is, they do not add value. The research pursues to design and apply a systematic methodology to improve efficiency of a manufacturing plant increasing the value-added towards the end-customer. The objective of the work is to carry out an analysis of the manufacturing process of charged detonators to be potentially applied for other sectors. With the development of this work, it is described how it is possible to analyze, assess and implement improvement tools in manufacturing systems with a long tradition and that to date have not needed to improve their processes significantly due to market dynamics such as manufacturing of detonators. Moreover, a work methodology for optimizing manufacturing plants based on the proposed tools can be applied to other sectors.