23,712 research outputs found

    Development of step-compliant system for turn-mill operations

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    Today with the latest technology the information beyond tool movement and switching instruction such as tooling, manufacturing features and process sequences are needed to support global adaptability for manufacturing with a specific focus on CNC-based manufacture. This research focuses on the use of the new standard; ISO 14649 (STEP-NC), to address the process planning and machining of discrete turn/mill components and proposes a STEP Compliant NC structure for generation of ISO 14646 code which can be used for turning component manufacture. The novel application of this work is STEP-NC compliant process control where the research will utilise and extend the standard for in process measurement at the machine and also explore the application and integration of the STEP-NC standards. The major contribution of this research is the review of a computational environment for a STEPNC compliant system for turn/mill operations by focusing the outlines of the three major CAD/CAM frameworks to support the implementation of the standard with various levels of STEP compliant architecture. Issues related to the implementation of these frameworks and their use with STEP compliant NC controllers provide a major change in the current day use of CAD, CAPP, CAM and CNC systems. This change will bring new challenges to industrial users and software vendors to identify the new boundaries and define intelligent CNC manufacture in the 21st century

    Intelligent composite layup by the application of low cost tracking and projection technologies

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    Hand layup is still the dominant forming process for the creation of the widest range of complex geometry and mixed material composite parts. However, this process is still poorly understood and informed, limiting productivity. This paper seeks to address this issue by proposing a novel and low cost system enabling a laminator to be guided in real-time, based on a predetermined instruction set, thus improving the standardisation of produced components. Within this paper the current methodologies are critiqued and future trends are predicted, prior to introducing the required input and outputs, and developing the implemented system. As a demonstrator a U-Shaped component typical of the complex geometry found in many difficult to manufacture composite parts was chosen, and its drapeability assessed by the use of a kinematic drape simulation tool. An experienced laminator's knowledgebase was then used to divide the tool into a finite number of features, with layup conducted by projecting and sequentially highlighting target features while tracking a laminator's hand movements across the ply. The system has been implemented with affordable hardware and demonstrates tangible benefits in comparison to currently employed laser-based systems. It has shown remarkable success to date, with rapid Technology Readiness Level advancement. This is a major stepping stone towards augmenting manual labour, with further benefits including more appropriate automation

    Effects of Gravity and Non-Perpendicularity during Powder-Fed Directed Energy Deposition of Ni-Based Alloy 718 through Two Types of Coaxial Nozzle

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    The consequences of gravity and the nozzle inclination angle in the powder-fed Directed Energy Deposition (DED) process were examined in this study. We also sought to define guidelines and manufacturing strategies, depending on the DED system configuration and the nozzle type. To do so, two nozzle types were used: a continuous coaxial nozzle with a slit of 0.5 mm and a four-stream discrete coaxial nozzle. Although the main effects of the configurations and the nozzles are well-known, their effects on the clad characteristics and the deposition strategy are as yet unclear. In this paper, measurements of a single clad and the effects of different deposition strategies on cladding applications and inclined walls are presented, and the consequences for manufacturing processes are discussed. Based on a complete study of a single clad, working vertically, five different tilted deposition strategies were applied: three to a single clad and two to an inclined wall. The results for both the single clad and the inclined wall reflect a pattern of changes to height, width, area, and efficiency, at both small and large nozzle angles and deposition strategies. The inclined wall presents a maximum horizontal displacement that can be reached per layer, without geometrical distortions. The amount of material per layer has to be adapted to this limitation.This research was funded by the European Commission through the project "PARADDISE: a Productive, Affordable and Reliable solution for large scale manufacturing of metallic components by combining laser-based Additive and Subtractive processes with high Efficiency” (Grant Agreement 723440), an initiative of the Public–Private Partnership “Photonics and Factories of the Future”. This research was also funded by European Institute of Innovation & Technology (EIT), through the project "DEDALUS: Directed Energy Deposition machines with integrated process ALgorithms Under dedicated monitoring and control System” (ID 20094), and by the vice-counseling of technology, innovation and competitiveness of the Basque Government (Eusko Jaurlaritza), under the ELKARTEK Program, PROCODA project, grant number KK-2019/00004

    An evaluation of important criteria for measuring the facade condition of old shophouses in Malaysia

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    Preserving the facade of the old shop houses is important to reflect the image of an attractive townscape. Be-sides having a unique architectural motif, the facade of an old shop houses also has a high heritage value, particularly in terms of how it was built. Therefore, it is desirable to ensure the facade is always in good condition. However, it is difficult to determine the facade of the old shop houses that whether they are in good condition or not. This is because there are no specific criteria used to classify the condition of the facade. Therefore, this study aims to establish a system of criteria for which the facade of the old shop houses that can be assessed and classified in a comprehensive and sustainable. A total of 74 respondents from various professional fields including industry practitioners and academics have been involved in com-pleting the questionnaire. The results of this study will then be used as a basis for the establishment of the classification model for building facade of old shop houses in Malaysia

    Technology challenges for space interferometry: the option of mid-infrared integrated optics

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    Nulling interferometry is a technique providing high angular resolution which is the core of the space missions Darwin and the Terrestrail Planet Finder. The first objective is to reach a deep degree of starlight cancelation in the range 6 -- 20 microns, in order to observe and to characterize the signal from an Earth-like planet. Among the numerous technological challenges involved in these missions, the question of the beam combination and wavefront filtering has an important place. A single-mode integrated optics (IO) beam combiner could support both the functions of filtering and the interferometric combination, simplifying the instrumental design. Such a perspective has been explored in this work within the project Integrated Optics for Darwin (IODA), which aims at developing a first IO combiner in the mid-infrared. The solutions reviewed here to manufacture the combiner are based on infrared dielectric materials on one side, and on metallic conductive waveguides on the other side. With this work, additional inputs are offered to pursue the investigation on mid-infrared photonics devices.Comment: Accepted in Adv. in Space Researc

    Low-background temperature sensors fabricated on parylene substrates

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    Temperature sensors fabricated from ultra-low radioactivity materials have been developed for low-background experiments searching for neutrinoless double-beta decay and the interactions of WIMP dark matter. The sensors consist of electrical traces photolithographically-patterned onto substrates of vapor-deposited parylene. They are demonstrated to function as expected, to do so reliably and robustly, and to be highly radio-pure. This work is a proof-of-concept study of a technology that can be applied to broad class of electronic circuits used in low-background experiments

    Video pembelajaran animasi atas talian bagi teknologi pemesinan

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    Pembelajaran atas talian merupakan salah satu medium pembelajaran yang perlu diinovasikan dalam kaedah penyampaian maklumat kepada pelajar. Kajian ini melaporkan tentang pembangunan video pembelajaran atas talian bagi kursus Teknologi Pemesinan. bagi meningkatkan minat pelajar Pendidikan Teknik dan Vokasional (PTV) dalam proses P&P. Reka bentuk kajian ini adalah membangunkan produk iaitu pembangunan video pembelajaran berdasarkan model PIE. Metodologi pembangunan objek pembelajaran melibatkan fasa Perancangan, Perlaksanaan dan penilaian. Kajian ini adalah berdasarkan pembangunan produk berdasarkan pengesahan pakar bagi membangunan dan menilai produk. Kajian ini dibangunkan berdasarkan pengesahan pakar bagi menilai pembangunan video. Instrumen penilaian objek pembelajaran ini dibangunkan bagi menilai elemen multimedia yang terdiri dari aspek teks, audio, animasi, grafik dan isi kandungan pengajaran dan pembelajaran. Dapatan kajian menunjukkan persembahan keseluruhan video pembelajaran yang menggunakan website (wix.com) ini adalah sesuai dan menarik untuk P&P bagi kursus Teknologi Pemesinan

    Toolpaths Programming in an Intelligent Step-NC Manufacturing Context

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    The current language for CNC programming is G-code which dates from the beginning of the eighties with the norm ISO 6983. With the new technologies, G-code becomes obsolete. It presents drawbacks that create a rupture in the numerical chain at the manufacturing step. A new standard, STEP-NC, aims to overtake these lacks. A STEP-NC file includes all the information for manufacturing, as geometry description of the entities, workplan, machining strategies, tools, etc. For rough pocket milling, the ISO norms propose different kind of classical strategies as bidirectional, parallel or spiral contour, etc. This paper describes a new way of toolpath programming by the repetition of a pattern all along a guide curve. It presents several advantages as building fastness and easiness. The integration of pattern strategies in STEP-NC standard is an other step for the development of these strategies but also for the enrichment of STEP-NC possibilities. A complete STEP-NC numerical chain was built, integrating these pattern strategies. The implementation of this approach of building pattern strategies was made by the development of tools for the complete manufacturing cycle, from the CAD file to the machined part. Several application cases were experimented on machine tool to validate this approach and the efficiency of the developped tools

    Model-based observer proposal for surface roughness monitoring

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    Comunicación presentada a MESIC 2019 8th Manufacturing Engineering Society International Conference (Madrid, 19-21 de Junio de 2019)In the literature, many different machining monitoring systems for surface roughness and tool condition have been proposed and validated experimentally. However, these approaches commonly require costly equipment and experimentation. In this paper, we propose an alternative monitoring system for surface roughness based on a model-based observer considering simple relationships between tool wear, power consumption and surface roughness. The system estimates the surface roughness according to simple models and updates the estimation fusing the information from quality inspection and power consumption. This monitoring strategy is aligned with the industry 4.0 practices and promotes the fusion of data at different shop-floor levels
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