Development of a design feature database to support design for additive manufacturing (DfAM)

This research introduces a method to aid the design of products or parts to be made using Additive Manufacturing (AM), particularly the laser sintering (LS) system. The research began with a literature review that encompassed the subjects of design and AM and through this the need for an assistive design approach for AM was identified. Undertaking the literature review also confirmed that little has been done in the area of supporting the design of AM parts or products. Preliminary investigations were conducted to identify the design factors to consider for AM. Two preliminary investigations were conducted, the first investigation was conducted to identify the reasons for designing for AM, the need for a design support tool for AM and current challenges of student industrial designers designing parts or products for AM, and also to identify the type of design support they required. Further investigation were conducted to examine how AM products are developed by professional industrial designers and to understand their design processes and procedures. The study has identified specific AM enabled design features that the designers have been able to create within their case study products. Detailed observation of the case study products and parts reveals a number of features that are only economical or possible to produce with AM. A taxonomy of AM enabled design features was developed as a precursor for the development of a computer based design tool. The AM enabled design features was defined as a features that would be uneconomical or very expensive to be produced with conventional methods. The taxonomy has four top-level taxons based on four main reasons for using AM, namely user fit requirements, improved product functionality requirements, parts consolidation requirements and improvement of aesthetics or form requirements. Each of these requirements was expanded further into thirteen sub categories of applications that contained 106 examples of design features that are only possible to manufacture using AM technology. The collected and grouped design features were presented in a form of a database as a method to aid product design of parts or products for AM. A series of user trials were conducted that showed the database enabled industrial designers to visualise and gather design feature information that could be incorporated into their own design work. Finally, conclusions are drawn and suggestions for future work are listed. In summary, it can be concluded that this research project has been a success, having addressed all of the objectives that were identified at its outset. From the user trial results, it is clear to see that the proposed tool would be an effective tool to support product design for AM, particularly from an educational perspective. The tool was found to be beneficial to student designers to take advantage of the design freedom offered by AM in order to produce improved product design. As AM becomes more widely used, it is anticipated that new design features will emerge that could be included in future versions of the database so that it will remain a rich source of inspirational information for tomorrow s industrial designers

Development of a design feature database to support design for additive manufacturing (DfAM)

This research introduces a method to aid the design of products or parts to be made using Additive Manufacturing (AM), particularly the laser sintering (LS) system. The research began with a literature review that encompassed the subjects of design and AM and through this the need for an assistive design approach for AM was identified. Undertaking the literature review also confirmed that little has been done in the area of supporting the design of AM parts or products. Preliminary investigations were conducted to identify the design factors to consider for AM. Two preliminary investigations were conducted, the first investigation was conducted to identify the reasons for designing for AM, the need for a design support tool for AM and current challenges of student industrial designers designing parts or products for AM, and also to identify the type of design support they required. Further investigation were conducted to examine how AM products are developed by professional industrial designers and to understand their design processes and procedures. The study has identified specific AM enabled design features that the designers have been able to create within their case study products. Detailed observation of the case study products and parts reveals a number of features that are only economical or possible to produce with AM. A taxonomy of AM enabled design features was developed as a precursor for the development of a computer based design tool. The AM enabled design features was defined as a features that would be uneconomical or very expensive to be produced with conventional methods. The taxonomy has four top-level taxons based on four main reasons for using AM, namely user fit requirements, improved product functionality requirements, parts consolidation requirements and improvement of aesthetics or form requirements. Each of these requirements was expanded further into thirteen sub categories of applications that contained 106 examples of design features that are only possible to manufacture using AM technology. The collected and grouped design features were presented in a form of a database as a method to aid product design of parts or products for AM. A series of user trials were conducted that showed the database enabled industrial designers to visualise and gather design feature information that could be incorporated into their own design work. Finally, conclusions are drawn and suggestions for future work are listed. In summary, it can be concluded that this research project has been a success, having addressed all of the objectives that were identified at its outset. From the user trial results, it is clear to see that the proposed tool would be an effective tool to support product design for AM, particularly from an educational perspective. The tool was found to be beneficial to student designers to take advantage of the design freedom offered by AM in order to produce improved product design. As AM becomes more widely used, it is anticipated that new design features will emerge that could be included in future versions of the database so that it will remain a rich source of inspirational information for tomorrow s industrial designers.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Stab Resistant Analysis of Body Armour Design Features Manufactured via Fused Deposition Modelling Process

Five designs of imbricate scale armour features for stab-resistant application were printed via fused deposition modelling process. Stab test on these designs against the HOSDB KR1-E1 stab-resistant body armour standard with impact energy of 24 Joules was conducted. The stab test was conducted on a number of samples measured thicknesses ranging from 4.0 to 10.0 mm by using Instron CEAST 9340 Drop Impact Tower to determine a minimum thickness that resulted in a knife penetration through the underside of sample which does not exceed the maximum penetration permissibility of 7.0 mm. Materials used for the samples were ABS-M30 and PC-ABS. Finally, one of the designs which offered the highest knife penetration resistance was selected. The results show that PC-ABS samples provide less shattering and lower overall knife penetration depth in comparison with ABS-M30. PC-ABS stab test demonstrated a minimum thickness of 8.0 mm, which was the most adequate to be used in the development of FDM manufactured body armour design features. Lastly, the design feature of D5 has shown to exhibit the highest resistance to the knife penetration due to the penetration depth of 3.02 mm, which was the lowest compared to other design features

Vacuum System Assisted Fdm – Characteristic Of Heat Transfer Using Finite Element Analysis

Fused deposition modeling (FDM) process is one of the most efficient and used additive manufacturing technologies. For years, building functional components with good mechanical strength has been a difficult task. Generally, FDM process is operated in a room with or without an enclosure to produce physical polymer components. Therefore, the inconsistencies from different environmental factor such as temperature and air quality have indirectly affected its quality build. Vacuum technology has been used in the wide area of applications by creating an empty space of matter. However, there is no investigation of FDM operated in a vacuum environment. This paper aims to study the behaviour of the temperature inside a vacuum assisted FDM by performing finite element analysis. A heated nozzle and heated bed will be placed inside a vacuum chamber with a constant heat source and the initial temperature set at room temperature. The pressure range from 30 inHg (1 atm) to 1 inHg will be the manipulated variable. The result shows that as the pressure decreases, the transient heat transfer (natural convective heating) also reduced and the velocity of air flow became more consistent. This study was able to prove how different vacuum pressures can affect the heat inside a vacuum chamber. Results from this study can be used to further analyse the mechanical strength of vacuumed printed components in actual experimentation

Influence of Integrated Pressing during Fused Filament Fabrication on Tensile Strength and Porosity / Siti Najatul Aishah Majid...[et al.]

Additive manufacturing or 3D printing is a technology that built 3D objects by adding material layer-by-layer. There are tremendous studies have been conducted regarding this new emerging technology to transform the printed part from being a prototyping tool to a manufacturing process that can create durable and functional goods, and comparable to the traditional manufacturing processes. Therefore, this study proposes a new method of Fused Filament Fabrication (FFF) by integrating with mechanical pressing where a roller is used to improve the strength and porosity of the printed part during processing. This study focuses on the low-range RepRap 3D printer. Mendel RepRap was used to print the samples, and the material of Acrylonitrile-butadiene-styrene (ABS) was used for this study. The samples printed from both techniques, normal FFF and FFF with pressing were compared with respect to their tensile strength and porosity. The strength of the samples was tested using an Instron machine, and the images of the samples were captured using Scanning Electron Microscope (SEM). Later, Image J software was used to analyze and calculate the percentage of the porosity. Based on the results, the percentage of porosity for the normal FFF is about 20~21% while FFF with pressing shows the smaller value that ranges from 12~15%. Meanwhile, the tensile strength of the FFF with pressing gave a greater value which is up to 38.34 Mpa

A Proposal for a Methodology of Technical Creativity Mixing TRIZ and Additive Manufacturing

The industry has quickly realized the importance of bringing creativity into product design. The industrial context requires robust and efficient methods and tools to access untapped sources of ideas. Furthermore, Additive Manufacturing (AM) offers a large potential of creativity for product design. This potential is particularly significant at the level of Intermediate Objects. Previous works have demonstrated the interest of AM Intermediate Objects (Rias, 2017) in creativity phases. This new manufacturing process is revolutionizing the value chain associated with product design, from the ideation to the industrialization. The purpose of this paper is to describe the bases for proposing a methodology of technical creativity based on TRIZ and Additive Manufacturing.This research was carried out as part of project CREAM (CREativity in Additive Manufacturing), funded by the National Research Agency (project ANR-18-CE10-0010) in France

DESIGN RULES OPTIMIZATION IN DESIGNING OF SHEET METAL PART

This research addressed the design rules optimization of sheet metal part for typical industry that will aid designers through design process stage. Design is the most important and an expensive stage in the product development process. Design of sheet metal parts is greatly dependent on manufacturing experiences, which have to be documented and incorporated in design process stage. It would eliminate frequent redesign of part, after being assessed as infeasible or costly for manufacture in design stage. Through design of experiment would reduce a number of design rules significantly. This research aim to optimize a comprehensive set of design rules for design of sheet metal part and develop a design of experiment (DOE) for implementing inter-feature design rule for reducing infeasible design, cost and production cycle times