Gynaecological product development facilitated through RP and Rapid Tooling

Published ArticleAtkinson distinguishes between four types of prototypes, categorised through its end-use: •Design or aesthetic prototypes •Geometrical prototypes •Functional prototypes •Technological prototypes Shigley and Mitchell define the design process according to the following six phases: Recognition of need Definition of problem Synthesis Analysis and optimization Evaluation Presentation The Centre for Rapid Prototyping and Manufacture (CRPM) of the Central University of Technology, Free State was asked to assist in the development of a newly developed gynaecological cream applicator. Apart from needing a freeform fabrication system to give form fit and function to the very complex design, the product needed Rapid Tooling / Rapid Manufacturing support to enable a first batch production for medical trials and evaluation. The paper will describe the total product development process alongside prototype categories described by Atkinson and design phases defined by Shigley and Mitchell (including some iterations enabled through timeous prototyping, including various Rapid Prototyping (RP) Technologies, soft tooling and vacuum casting). More importantly, results from Rapid Tooling for limited run production (due to the complexity of the product the cycle time of the Prototype Tool is fairly long), as well as the economical impact made possible through the support of CAD / CAM and RP Technologies, will be discussed

BENCHMARKING OF FDM PRINTED REPLACEMENT PARTS FOR RURAL WHEELCHAIRS

ArticleMany disabled patients rely on wheelchairs for mobility to participate as equal citizens within society. Wheelchairs supplied through state healthcare are often not well suited to especially rural conditions and often break-down. This study investigates if entry level Fused Deposition Modelling (FDM) can be used to produce front caster wheels and seat post guides that commonly fail on wheelchairs. Results of the study has shown that these parts can be produced with good quality and at reasonable cost through FDM. The ability to manufacture custom made parts on request through FDM was shown to be a real advantage to supply hard to source wheelchair parts in the rural communities

DIRECT METAL LASER SINTERING, USING CONFORMAL COOLING, FOR HIGH VOLUME PRODUCTION TOOLING#

Published ArticleExisting techniques to manufacture conventional tool steel inserts for the plastic injection moulding process are expensive and time-consuming. Complex mould inserts, difficult to manufacture with conventional processes, can be produced using Direct Metal Laser Sintering (DMLS) with Maraging tool steel (MS1). MS1 is an additive manufacturing (AM) material made available by Electro Optical Systems (EOS) GmbH. Contrary to material removal processes, DMLS can produce MS1 tool steel inserts directly from Computer-Aided Design (CAD) files suitable for high volume plastic injection moulding. Through DMLS it is possible to create conformal cooling channels inside the MS1 inserts that have advantages in reducing heat rapidly and evenly. This can result in a reduction of cycle times, cost per product as well as improving part quality by eliminating defects such as warpage and heat sinks. This paper will present a comparison between Finite Element Analysis (FEA) simulations of the injection mould inserts with actual mould trails of AM and conventional manufactured inserts. It also includes the design and manufacturing of conventional and DMLS inserts and compares the manufacturing costs and lead times. Using FEA simulations, the design of conformal cooling channels is optimised by comparing the mould temperature of different cooling channel layouts. Bestaande tegnieke vir die vervaardiging van matryse vir die plastiek-inspuit giet tegniek is duur en tyd rowend. Verder is dit nie altyd moontlik om konvensionele metodes vir die vervaardiging van matryse vir geomteries komplekse gietstukke te gebruik nie. Vir sodanige gietsukke kan invoegsels relatief vinnig vervaardig word, deur van direkte laser metal sinterings metodes (DLMS) met Maraging-staal (MS1) gebruik te maak. MS1 is ’n laag vervaardings materiaal wat onlangs deur Electro Optical Systems (EOS) GmbH beskikbaar gestel is. Dit is ’n pre-allooi, ultra hoë sterkte metaal met goeie meganiese eienskappe. In teenstelling met materiaal verwyderings prosesse (masjienerings prosesse), kan DMLS MS1 staal matryse of insetsels wat vir hoë volume produksie van plastiek gietsukke bruikbaar is, direk vanaf rekenaar-gesteunde ontwerp prosesse vervaardig word. Die gebruik van DMLS kan ook vir die ontwerp en vervaardiging van vorm getroue verkoelings kanale in matryse voorsiening maak, wat tot laer hitte asook die vinnige en eweredige verspreiding daarvan sal lei. Voorgenoemde behoort tot ’n aansienlike verlaging in produksie siklus tye te lei met ’n dien ooreenkomstige verlaging in die produksie koste asook ’n verbetering in die kwaliteit van die vervaardigde produkte a.g.v. die voorkoming van defekte soos kromtrekking en hitte-putte wat normaalweg deur oneweredige hitte verspreiding veroorsaak word

Evaluating the Suitability of Alumide Tooling for Injection Moulding of Different Polymers

Published ArticleThis paper describes the possibility of using laser-sintered Alumide® as an alternative material for producing rapid tooling (RT) inserts. To determine the durability of Alumide® inserts for the injection moulding (IM) process, a product with geometrical features was developed, and Alumide® inserts were manufactured. Polypropylene (PP), acrylonitrile-butadiene-styrene (ABS), polycarbonate (PC), and polyamide 6 (PA 6) were used for IM trials with the Alumide® inserts. From these trials, it was concluded that polymer materials with a processing temperature of about 230 ºC, similar to PP and ABS, can be used with Alumide® inserts as RT inserts for the IM process

Developing a Patient-Specific Maxillary Implant Using Additive Manufacturing and Design

Published Conference ProceedingsMaxillectomy is the surgical removal or resection of the maxilla or upper jaw bone. A total or partial maxillectomy can be performed depending on how far the tumour has spread. This paper will discuss a patient diagnosed with an aggressive tumour in half of the top jaw who had to undergo an operation to remove the hemi-maxilla and orbital floor. Due to the extent and complexity of the defect, it was decided to manufacture an anatomical model of the hard tissues for planning a possible laser-sintered titanium implant using Additive Manufacturing (AM). The CRPM had only two weeks to design and manufacture the titanium implant, due to the severity of the tumour. The anatomical model was sent to the surgeon to cut the nylon model where the bone resection was planned. Furthermore, the prosthodontist made a wax model of the planned titanium frame that was reverse- engineered and used as reference geometry in the design software.Materialise® design suite was used to design the patient-specific maxilla and cutting jig. The EOS M280 Direct Metal Laser Sintering (DMLS) system was instrumental in achieving the direct manufacturing of the bio-compatible titanium implant. The EOS P385 system was used to manufacture the pre-operation planning model as well as the cutting jig.The process chain followed to complete this case study will be discussed showing how this intervention improved the quality of life of a SA patient. Furthermore, the proposed paper and presentation will discuss the post-operation review of the patient showing the impact AM had in accelerating patient-specific implant manufacturing. The authors seek to claim a progressed level of maturity in the proposed manufacturing value chain. The claim is based on the successful completion of the analysis and synthesis of the problem , the validated proof-of-concept of the manufacturing process and the in-vivo implementation of the final product

Client-centred design evolution via functional prototyping

The product design process involves communication of potential design solutions to customers. Fully functional prototypes are most suitable for this because they are readily accepted and allow simultaneous evaluation of all design criteria. However, they are often seen as expensive, time-consuming and not fully representative of the final product material. Therefore, they are usually reserved for customer validation of the final design rather than to keep them involved in every product evolution iteration. This research proposes that rapid prototypes should be used to facilitate a method referred to as Customer Interaction through Functional Prototypes (CIFP). An action research methodology was employed to test the efficacy of applying this method to a real-world product design brief. Customers were able to fully evaluate the aesthetic, ergonomic and functional parameters of the product during every design iteration. This resulted in accelerated product development, sensitivity to the client's needs, a new dimension of 'natural' communication and a successful product design

Cost-Effectiveness of Direct Metal Laser Sintered Maraging Steel Inserts For Plastic Injection Moulding Process

Published ArticleThis paper describes an investigation into the possible heat transfer benefits of conformal cooling channels using maraging steel MS1 inserts, which could result in a reduction of cycle times and cost per product, and improve part quality by eliminating defects such as warpage and heat sinks. A manufacturing cost and lead-time comparison showed that a conventionally manufactured insert reached its break-even point after fewer injection moulding cycles than an additive manufactured insert, due to its lower manufacturing costs. During high-volume production, the additive manufactured insert becomes more profitable to use, due to its shorter cycle times

Track D Social Science, Human Rights and Political Science

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138414/1/jia218442.pd

Rapid prototyping and manufacturing in medical product development

Published ArticleRP and recently RM have been key factors in the development of the manufacturing industry in assisting in the development of new products. Fortunately, the application of these technologies has been realised in the medical industry. Surgeons all over the world use physical models created from CT or MRI data using some sort of additive manufacturing. The fabrication of these models has exploded into a popular research area combining engineering, material and medical expertise. Long-term growth in the additive fabrication industry will come from designs that are difficult, time-consuming, costly, or impossible to produce using standard techniques. Growth will occur with advances in current additive processes which are coupled with breakthroughs in new materials. The applications of RP and RM are as diverse as the medical issues that arise. RM of custom design medical prostheses proves to be economically viable solution, not only because it is faster to produce but it gives the designer freedom of creation too. The paper discusses some interesting medical case studies

Rapid Prototyping (through SLS) as Visualisation Aids for Architectural Use

The Cambridge International Dictionary of English, explains the word "Design" as a "pattern used to decorate something". Whilst this very narrow-minded definition can spark a debate on the meaning of design, it does however imply, that something has to made or manufactured, following a process-chain which started with an idea, followed by the design, and finally, the new product. As Functional Design is closely linked to inter alia manufacturing and building, Designers' freedom to express themselves, are often limited by the capabilities of craftsmen who have to give physical substance to Designer's ideas. The recently completed Manufacturing and Materials national FORESIGHT report [1] from the Department of Arts, Culture, Science and Technology (DACST) of the South African Government shows that manufacturers wishing to compete internationally should focus on integrated product, process and production system design, to speed up production time. This is all encapsulated in Concurrent Engineering, where design and approval are configured into a parallel, iterative process. Whilst it is not only dependent of technologies, technology and enabling tools such as Rapid Prototyping, applied in an integrated process, are crucial in the successful application of Concurrent Engineering. In the past a series of technologies, e.g. CAD, CAM and NC manufacturing was identified to solve these problems. Rapid Prototyping, Solid Freeform Fabrication or Generative Manufacturing - which are all synonyms for new methods of building physical parts directly from CAD data - represent the latest trends in manufacturing technology. However, all these techniques represent only a technological view on how product development can meet the tremendous challenges of the future. In fact, not merely the use of a single technology provides better products faster for the market, but the integration of a large number of technologies and methodologies. Therefore, aspects of information processing, cost, quality and time management, team work, organisational issues and many other enabling technologies like data highways, multi-media or distributed databases have to be taken into account as well. Rapid Prototyping is being used more and more as a key enabling technology in reducing the time to market for new products, by identifying possible design flaws prior to tooling and manufacturing, and is providing the common focus for multidisciplinary groups, around which to resolve design and development questions. Barkan and Iansti present RP as a means of rapid learning at every stage of the design process. Adopting this view on the whole of the development process, one comes to the conclusion that the use of RP to enable Rapid Product Development, is a fundamental challenge that must be addressed by all manufacturers to remain competitive in today's global market place. 35 In defining manufacturing, one tends to think about plastic products, casting, tooling concerned, and mass production. Whilst this represents the latest trends in manufacturing, one of the oldest methods of manufacturing however, is the conversion of basic raw materials into accommodation, shelters, etc. In adopting Rapid Prototyping and related technologies into the built and architecture environment, numerous new opportunities open up. The paper describes a fresh approach into an age-old industry.Mechanical Engineerin