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Article
Publication date: 1 August 2003

L.C. Hieu, E. Bohez, J. Vander Sloten, H.N. Phien, E. Vatcharaporn, P.H. Binh, P.V. An and P. Oris

Design methods for medical rapid prototyping (RP) of personalized cranioplasty implants are presented in this paper. These methods are applicable to model cranioplasty implants…

2359

Abstract

Design methods for medical rapid prototyping (RP) of personalized cranioplasty implants are presented in this paper. These methods are applicable to model cranioplasty implants for all types of the skull defects including beyond‐midline and multiple defects. The methods are based on two types of anatomical data, solid bone models (STereoLithography files – STL) and bone slice contours (Initial Graphics Exchange Specification – IGES and StrataSys Layer files – SSL). The bone solids and contours are constructed based on computed tomography scanning data, and these data are generated in medical image processing and STL slicing packages.

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Rapid Prototyping Journal, vol. 9 no. 3
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 1 December 2005

L.C. Hieu, N. Zlatov, J. Vander Sloten, E. Bohez, L. Khanh, P.H. Binh, P. Oris and Y. Toshev

Aims to investigate medical rapid prototyping (medical RP) technology applications and methods based on reverse engineering (RE) and medical imaging data.

5529

Abstract

Purpose

Aims to investigate medical rapid prototyping (medical RP) technology applications and methods based on reverse engineering (RE) and medical imaging data.

Design/methodology/approach

Medical image processing and RE are applied to construct three‐dimensional models of anatomical structures, from which custom‐made (personalized) medical applications are developed.

Findings

The investigated methods were successfully used for design and manufacturing of biomodels, surgical aid tools, implants, medical devices and surgical training models. More than 40 medical RP applications were implemented in Europe and Asia since 1999.

Research limitations/implications

Medical RP is a multi‐discipline area. It involves in many human resources and requires high skills and know‐how in both engineering and medicine. In addition, medical RP applications are expensive, especially for low‐income countries. These practically limit its benefits and applications in hospitals.

Practical implications

In order to transfer medical RP into hospitals successfully, a good link and close collaboration between medical and engineering sites should be established. Moreover, new medical applications should be developed in the way that does not change the traditional approaches that medical doctors (MD) were trained, but provides solutions to improve the diagnosis and treatment quality.

Originality/value

The presented state‐of‐the‐art medical RP is applied for diagnosis and treatment in the following medical areas: cranio‐maxillofacial and dental surgery, neurosurgery, orthopedics, orthosis and tissue engineering. The paper is useful for MD (radiologists and surgeons), biomedical and RP/CAD/CAM engineers.

Details

Assembly Automation, vol. 25 no. 4
Type: Research Article
ISSN: 0144-5154

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Article
Publication date: 16 January 2017

AmirMahyar Khorasani, Ian Gibson, Moshe Goldberg and Guy Littlefair

The purpose of this paper is to improve the manufacturing of a prosthetic acetabular shell by analyzing the main factors leading to failure during the selective laser melting…

740

Abstract

Purpose

The purpose of this paper is to improve the manufacturing of a prosthetic acetabular shell by analyzing the main factors leading to failure during the selective laser melting (SLM) additive manufacturing (AM) process.

Design/methodology/approach

Different computer-aided design and computer-aided manufacturing processes have been applied to fabricate acetabular parts. Then, various investigations into surface quality, mechanical properties and microstructure have been carried out to scrutinize the possible limitations in fabrication.

Findings

Geometrical measurements showed 1.59 and 0.27 per cent differences between the designed and manufactured prototypes for inside and outside diameter, respectively. However, resulting studies showed that unstable surfaces, cracks, an interruption in powder delivery and low surface quality were the main problems that occurred during this process. These results indicate that SLM is an accurate and promising method for production of intricate shapes, provided that the appropriate settings of production conditions are considered to minimize possible limitations.

Originality/value

The contributions of this paper are discussions covering different issues in the AM fabrication of acetabular shells to improve the mechanical properties, quality and durability of the produced parts.

Details

Rapid Prototyping Journal, vol. 23 no. 1
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 27 September 2021

Michele Ciotti, Giampaolo Campana and Mattia Mele

This paper aims to present a survey concerning the accuracy of thermoplastic polymeric parts fabricated by additive manufacturing (AM). Based on the scientific literature, the aim…

406

Abstract

Purpose

This paper aims to present a survey concerning the accuracy of thermoplastic polymeric parts fabricated by additive manufacturing (AM). Based on the scientific literature, the aim is to provide an updated map of trends and gaps in this relevant research field. Several technologies and investigation methods are examined, thus giving an overview and analysis of the growing body of research.

Design/methodology/approach

Permutations of keywords, which concern materials, technologies and the accuracy of thermoplastic polymeric parts fabricated by AM, are used for a systematic search in peer-review databases. The selected articles are screened and ranked to identify those that are more relevant. A bibliometric analysis is performed based on investigated materials and applied technologies of published papers. Finally, each paper is categorised and discussed by considering the implemented research methods.

Findings

The interest in the accuracy of additively manufactured thermoplastics is increasing. The principal sources of inaccuracies are those shrinkages occurring during part solidification. The analysis of the research methods shows a predominance of empirical approaches. Due to the experimental context, those achievements have consequently limited applicability. Analytical and numerical models, which generally require huge computational costs when applied to complex products, are also numerous and are investigated in detail. Several articles deal with artificial intelligence tools and are gaining more and more attention.

Originality/value

The cross-technology survey on the accuracy issue highlights the common critical aspects of thermoplastics transformed by AM. An updated map of the recent research literature is achieved. The analysis shows the advantages and limitations of different research methods in this field, providing an overview of research trends and gaps.

Details

Rapid Prototyping Journal, vol. 28 no. 2
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 18 January 2011

Ryszard Uklejewski, Mariusz Winiecki, Piotr Rogala and Janusz Mielniczuk

The aim of this paper is to present the main results of a research project finished in 2008 which concerned the selective laser melted (SLM) prototype of a new kind of minimally…

1365

Abstract

Purpose

The aim of this paper is to present the main results of a research project finished in 2008 which concerned the selective laser melted (SLM) prototype of a new kind of minimally invasive resurfacing hip arthroplasty (RHA) endoprosthesis with the original multi‐spiked connecting scaffold (MSC‐Scaffold). Previous attempts performed in pre‐Direct Metal Manufacturing (DMM) era demonstrated that it was impossible to manufacture suitable prototypes of this RHA endoprosthesis (especially of the MSC‐Scaffold) using traditional machining technologies. Owing to an extensive development of DMM technologies observed in recent years the manufacturing of such prototypes has become possible.

Design/methodology/approach

Computer aided design models of pre‐prototypes and the prototype of the RHA endoprosthesis with MSC‐Scaffold were designed and initially optimized within the claims and the general assumptions of international patents by Rogala. Prototyping in SLM technology was subcontracted to SLM Tech Center (Paderborn, Germany). Macroscopic and SEM microscopic evaluation of the MSC‐Scaffold was performed using SLM manufactured prototypes and paying special attention to the quality and precision of manufacturing.

Findings

It was found that SLM can be successfully applied to manufacturing of prototypes of the original minimally invasive RHA endoprosthesis. The manufacturing quality of the 3D spikes system of the MSC‐Scaffold, which mimics the interdigitations of articular subchondral bone, has been proved to be geometrically corresponding to the biological original. Nevertheless, some pores and non‐melted zones were found in SLM prototyped RHA endoprosthesis cross‐sections which need to be eliminated to minimize the potential risk of clinical failure.

Research limitations/implications

The presented case study was performed with a limited number of samples. More research needs to be performed on the rapid prototyped samples including microstructural and mechanical tests. The results may enable the optimization of the SLM manufacturing process of the prototypes of the minimally invasive RHA endoprosthesis with MSC‐Scaffold.

Practical implications

The SLM can be considered as potentially suitable for the fabrication of patient‐fitted minimally invasive RHA endoprostheses with MSC‐Scaffold.

Originality/value

For the first time, largely owing to SLM technology, it was possible to manufacture the prototype of the original minimally invasive RHA endoprosthesis with MSC‐Scaffold suitable for further research.

Details

Rapid Prototyping Journal, vol. 17 no. 1
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 3 April 2007

Michèle Truscott, Deon de Beer, George Vicatos, Keith Hosking, Ludrick Barnard, Gerrie Booysen and R. Ian Campbell

The last decade has seen major advances in rapid prototyping (RP), with it becoming a multi‐disciplinary technology, crossing various research fields, and connecting continents…

2002

Abstract

Purpose

The last decade has seen major advances in rapid prototyping (RP), with it becoming a multi‐disciplinary technology, crossing various research fields, and connecting continents. Process and material advancements open up new applications and manufacturing (through RP) is serving non‐traditional industries. RP technology is used to support rapid product development (RPD). The purpose of this paper is to describe how the Integrated Product Development research group of the Central University of Technology, Free State, South Africa is applying various CAD/CAM/RP technologies to support a medical team from the Grootte Schuur and Vincent Palotti hospitals in Cape Town, to save limbs – as a last resort at a stage where conventional medical techniques or practices may not apply any longer.

Design/methodology/approach

The paper uses action research to justify the proposal of a new method to use CAD/CAM/RP related technologies to substitute lost/damaged bone regions through the use of CT to CAD to.STL manipulation.

Findings

A case study where RP related technologies were used to support medical product development for a patient with severe injuries from a road accident is discussed.

Originality/value

The paper considers current available technologies, and discusses new advancements in direct metal freeform fabrication, and its potential to revolutionise the medical industry.

Details

Rapid Prototyping Journal, vol. 13 no. 2
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 12 March 2018

Donghua Zhao, Weizhong Guo, Baibing Zhang and Feng Gao

The purpose of this paper is to review available technologies, analyse their features, propose a new approach of 3D sand mould printing based on line forming, introduce the…

896

Abstract

Purpose

The purpose of this paper is to review available technologies, analyse their features, propose a new approach of 3D sand mould printing based on line forming, introduce the manufacturing principle and show advantages of this approach, especially for larger parts with large Z steps in the build, such as 2 mm stepwise.

Design/methodology/approach

This paper introduces 3D sand mould printing, compares and analyses technological process and existing fabrication approaches among available technologies first. Then, a new approach of 3D sand mould printing is proposed to improve build speed. In addition, the proposed system will be analysed or benchmarked against existing systems.

Findings

A new approach based on line forming of sand mould printing is put forward by reviewing and analysing available technologies, to improve build speed from the aspect of basic moulding movement instead of optimization of moulding methods and process parameters. The theoretical calculation and analysis shows that build speed can be improved greatly, and it is more suitable for the manufacture of large-scale casting’s sand mould when considering dimensional accuracy and printing error, as well as uniformity of each layer.

Research limitations/implications

The specific implement scheme of line forming and nozzle’s specific structure of this new approach need further study.

Practical implications

Much higher build speed of 3D sand mould printing with new approach brings evident implication for moulds companies and manufacturing industry, having a far-reaching influence on the development of national economy.

Originality/value

This paper reviews available technologies and presents a new approach of 3D sand mould printing for the first time. Analysis of the new approach shows that this new method of sand mould printing can boost build speed greatly. So, its application prospect is great.

Details

Rapid Prototyping Journal, vol. 24 no. 2
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 21 March 2016

Kamaljit Singh Boparai, Rupinder Singh and Harwinder Singh

The purpose of this study is to highlight the direct fabrication of rapid tooling (RT) with desired mechanical, tribological and thermal properties using fused deposition…

3819

Abstract

Purpose

The purpose of this study is to highlight the direct fabrication of rapid tooling (RT) with desired mechanical, tribological and thermal properties using fused deposition modelling (FDM) process. Further, the review paper demonstrated development procedure of alternative feedstock filament of low-cost composite material for FDM to extend the range of RT applications.

Design/methodology/approach

The alternative materials for FDM and their processing requirements for fabrication in filament form as reported by various researchers have been summarized. The literature demonstrates the role of various post-processing techniques on surface finish of FDM prints. Further, low-cost materials for feedstock filament have been investigated experimentally to check their adaptability/suitability for commercial FDM setup. The approach was to realize the requirements of FDM (melt flow rate, flexibility, stiffness, glass transition temperature and mechanical strength), necessary for the successful run of an alternative filament. The effect of constituents (additives, plasticizers, surfactants and fillers) in polymeric matrix on mechanical, tribological and thermal properties has been investigated.

Findings

It is possible to develop composite material feedstock as filament for commercial FDM setup without changing its hardware and software. Surface finish of the parts can further be improved by applying various post-processing techniques. Most of the composite parts have high mechanical strength, hardness, thermal stability, wear resistant and better bond formation than standard material parts.

Research limitations/implications

Future research may be focused on improving the surface quality of parts fabricated with composite feedstock, solving issues related to the uniform distribution of filled materials during the fabrication of feedstock filament which in turns further increases mechanical strength, high dimensional stability of composite filament and transferring the technology from laboratory scale to various industrial applications.

Practical implications

Potential applications of direct fabrication with RT includes rapid manufacturing (RM) of metal-filled parts and ceramic-filled parts (which have complex shape and cannot be rapidly made by any other manufacturing techniques) in the field of biomedical and dentistry.

Originality/value

This new manufacturing methodology is based on the proper selection and processing of various materials and additives to form high-performance, low-cost composite material feedstock filament (which fulfil the necessary requirements of FDM process). Finally, newly developed feedstock filament material has both quantitative and qualitative advantage in RT and RM applications as compared to standard material filament.

Details

Rapid Prototyping Journal, vol. 22 no. 2
Type: Research Article
ISSN: 1355-2546

Keywords

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Book part
Publication date: 24 October 2023

Lobat Asadi

There has been a reduction of arts funding the United States educational system, even though research has identified the need for socioemotional learning…

Abstract

There has been a reduction of arts funding the United States educational system, even though research has identified the need for socioemotional learning policy/guidelines/requirements in the US Ed. and more school teachers and counselors. In Texas, geopolitical issues and natural disasters impact learners in the state and corporal punishment is still allowed in some districts, such as Pampa Independent School District (ISD). A study of six art teachers across a large urban school district was conducted to better understand this conundrum vis-a-vis semi-structured interviews with art teachers working in public Middle and High Schools. This chapter investigates the impact of art practices and art teachers on socioemotional self-regulation of students, as we consider the impact on teacher retention using the Heuristic model of child self-regulation and reactivity and school outcomes (Liew, Erbeli, Nyanamba, & Li, 2020). Finally, the ironic finding that teaching art classes is financially emotionally draining for teachers to the point of decreasing retention, yet some are still impassioned to teach art classes, is juxtaposed with attachment theory. Recommendations for art education policy and pedagogy are made using the lens of socioemotional learning, art therapy, empathy, and emotional self-regulation.

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Article
Publication date: 5 December 2019

Mariusz Deja and Dawid Zielinski

The purpose of this study is to evaluate the geometric quality of small diameter holes in parts printed by direct metal laser sintering (DMLS) technology. An in-process optical…

213

Abstract

Purpose

The purpose of this study is to evaluate the geometric quality of small diameter holes in parts printed by direct metal laser sintering (DMLS) technology. An in-process optical inspection method is proposed and assessed during a pilot study. The influence of the theoretical hole diameter assumed in a computer-aided design (CAD) system and the sample thickness (hole length) on the hole clearance was analyzed.

Design/methodology/approach

The samples are made of two different materials: EOS MaragingSteel MS1 and aluminium alloy EOS Aluminium consisted of straight through holes of different diameters and lengths. Dimensional and shape accuracy of the holes were determined with the use of the image processing software and the computer analysis of two-dimensional (2-D) images. The definition of the equivalent hole diameter was proposed to calculate the hole clearance. Feret’s diameters were determined for the evaluation of the shape accuracy.

Findings

The dependency between the equivalent hole diameter and the theoretical diameter was approximated by the linear function for a specific sample thickness. Additionally, a general empirical model for determining the hole clearance was developed, allowing for calculating the equivalent hole diameter as a function of a sample thickness and a theoretical hole diameter.

Practical implications

Developed functions can be used by designers for a proper assignment of a hole diameter to achieve the required patency. The relevant procedures and macros based on proposed empirical models can be embedded in CAD systems to support the designing process.

Originality/value

The analysis of the geometric quality of the holes in parts printed by DMLS was based on the computer analysis of 2-D images. The proposed method of assessing the shape accuracy of straight through holes is relatively cheap, is widely available and can be applied to the features of other shapes produced by three-dimensional printing.

Details

Rapid Prototyping Journal, vol. 26 no. 2
Type: Research Article
ISSN: 1355-2546

Keywords

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