Investigating the Links between the Process Parameters and Their Influence on the Aesthetic Evaluation of Selective Laser Melted Parts

This study is a precursor to gaining a deeper understanding of how each parameter of the Additive Manufacturing (AM) process influences the aesthetic properties of 3D printed products. Little research has been conducted on this specific aspect of AM. Using insights from the work presented in this paper, we intend to develop design support tools to give the designer more control over the printed products in terms of aesthetics. In this initial work, we fabricated samples using Selective Laser Melting (SLM) technology, and investigated the parameters geometry, building strategy, and post-processing. We asked participants to evaluate the visual and physical interaction with the manufactured samples. Results show that, in addition to geometry and post-processing, the aesthetic evaluation can also be strongly influenced by the SLM process’ building strategy. This understanding will enable us to develop tools to give designers more control over the part’s aesthetic appearance. In addition, we present a systematic procedure and setup to evaluate the aesthetic appearance of products manufactured using AM

Design Methodology for Additive Manufacturing: Supporting Designers in the Exploitation of Additive Manufacturing Affordances

Mechatronic Desig

Man machine interface and product embodying such a man machine interface

Design EngineeringIndustrial Design Engineerin

3D Hatching: Linear halftoning for dual extrusion fused deposition modeling

This work presents halftoning techniques to manufacture 3D objects with the appearance of full grayscale imagery for Fused Deposition Modeling (FDM) printers. While droplet-based dithering is a common halftoning technique, this is not applicable to FDM printing, since FDM builds up objects by extruding material in semi-continuous paths. A set of three methods is presented which apply a linear halftoning principle called 'hatching' to horizontal, vertical and diagonal surfaces. These methods are better suited to FDM compared to other halftoning methods: their applicability stands irrespective of the geometry and surface slope and the perceived tone is less sensitive to the viewing angle. Furthermore, the methods have little effect on printing time. Experiments on a dual-nozzle FDM printer show promising results. Future work is required to optimize the interaction between the presented methods.</p

Xpandables: Single-filament Multi-property 3D Printing by Programmable Foaming

We propose a new approach to obtain local property variations in 3D-printed objects using a single-nozzle 3D printer and one filament. We use foaming filaments which expand at different rates due to different temperatures. We present an approach to harness this varying expansion by including parameters of the 3D printing process in the design space. This makes the foaming programmable and allows for achieving a wide variety of properties from a single material. We show how objects with locally varying shade, translucency, gloss, and texture can be fabricated. Our approach turns single-nozzle 3D printers into more versatile systems while eliminating the challenges of multi-material 3D printing. This is in contrast to the drive towards an increasing number of printable materials and more complex 3D printers. We demonstrate the capability of our approach by 3D printing objects with embedded barcodes, QR codes, and varying tactile properties.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Mechatronic Desig

First Steps Towards Collaboratively Edited Design for Additive Manufacturing Knowledge

Despite the broad coverage concerning the technological challenges, little research has been performed on the methods that enable designers to deal with Additive Manufacturing. At present, the challenge is to generate Design for Additive Manufacturing knowledge which goes beyond traditional solutions and to ensure that this knowledge is complete, correct and up to date. This paper reports on the employment of a wiki environment to support open-ended knowledge management. We applied this solution in an undergraduate prototyping course focused on exploring visual properties using AM structures. The results of the 32 students encompass unexpected designs while the knowledge on the wiki encompassed i) AM processes, ii) procedures, iii) artifacts. This forces us to rethink what should constitute DfAM.Mechanical Engineerin

Embracing the digital in instrument making: Towards a musician-tailored mouthpiece by 3D printing

At present, the manufacturing of musical instruments still strongly relies on the tacit knowledge of experienced handcrafts while is commonly based on standard machining or casting techniques. This limits the musician-tailoredness to a small group of players, while others take compromises by employing stock parts. The present article describes a new methodology for the design and production of woodwind instruments mouthpieces. By embracing digital modeling and manufacturing, this methodology encompasses four phases, which can be cut short when necessary. The aim of the presented methodology is to link the geometry of the mouthpiece to tone properties. Based on 3D printing, the inside geometry can be altered to complex and reproducible detail to obtain the desired acoustic features - eventually leading to mouthpiece geometries tailored to the player’s sound and playability requirements. The results of aerodynamic investigations together with the subjective experience of saxophone players have been used to design mouthpieces with modified inside geometries of both baffle and chamber. Prototypes have been produced at the Delft University of Technology (TU Delft) using several 3D printing technologies and different materials. Both professional and amateur saxophone players tested these at the Royal Conservatoire of The Hague and at the North Sea Jazz festival (Rotterdam 2012). Based on the judgment of the players, specific geometrical features were revealed to emphasize specific tone characteristics. A number of professional players are actively performing with our mouthpieces. The application and further development of the methodology will lead to a better empirical basis to reason about acoustics and playability, and can be applied to other instruments as well. Future work includes additional measurements and developing a parameterized datdatabase of 3D modelsDesign EngineeringIndustrial Design Engineerin

3D Hatching: Linear halftoning for dual extrusion fused deposition modeling

This work presents halftoning techniques to manufacture 3D objects with the appearance of full grayscale imagery for Fused Deposition Modeling (FDM) printers. While droplet-based dithering is a common halftoning technique, this is not applicable to FDM printing, since FDM builds up objects by extruding material in semi-continuous paths. A set of three methods is presented which apply a linear halftoning principle called 'hatching' to horizontal, vertical and diagonal surfaces. These methods are better suited to FDM compared to other halftoning methods: their applicability stands irrespective of the geometry and surface slope and the perceived tone is less sensitive to the viewing angle. Furthermore, the methods have little effect on printing time. Experiments on a dual-nozzle FDM printer show promising results. Future work is required to optimize the interaction between the presented methods.Mechatronic DesignMaterials and Manufacturin

Hatching for 3D prints: Line-based halftoning for dual extrusion fused deposition modeling

This work presents a halftoning technique to manufacture 3D objects with the appearance of continuous grayscale imagery for Fused Deposition Modeling (FDM) printers. While droplet-based dithering is a common halftoning technique, this is not applicable to FDM printing, since FDM builds up objects by extruding material in semi-continuous paths. The line-based halftoning principle called 'hatching' is applied to the line patterns naturally occuring in FDM prints, which are built up in a layer-by-layer fashion. The proposed halftoning technique isn't limited by the challenges existing techniques face; existing FDM coloring techniques greatly influence the surface geometry and deteriorate with surface slopes deviating from vertical or greatly influence the basic parameters of the printing process and thereby the structural properties of the resulting product. Furthermore, the proposed technique has little effect on printing time. Experiments on a dual-nozzle FDM printer show promising results. Future work is required to calibrate the perceived tone.Materials and ManufacturingMechatronic Desig

A Framework for Adaptive Width Control of Dense Contour-Parallel Toolpaths in Fused Deposition Modeling

3D printing techniques such as Fused Deposition Modeling (FDM) have enabled the fabrication of complex geometry quickly and cheaply. Objects are produced by filling (a portion of) the 2D polygons of consecutive layers with contour-parallel extrusion toolpaths. Uniform width toolpaths consisting of inward offsets from the outline polygons produce over- and underfill regions in the center of the shape, which are especially detrimental to the mechanical performance of thin parts. In order to fill shapes with arbitrary diameter densely the toolpaths require adaptive width. Existing approaches for generating toolpaths with adaptive width result in a large variation in widths, which for some hardware systems is difficult to realize accurately. In this paper we present a framework which supports multiple schemes to generate toolpaths with adaptive width, by employing a function to decide the number of beads and their widths. Furthermore, we propose a novel scheme which reduces extreme bead widths, while limiting the number of altered toolpaths. We statistically validate the effectiveness of our framework and this novel scheme on a data set of representative 3D models, and physically validate it by developing a technique, called back pressure compensation, for off-the-shelf FDM systems to effectively realize adaptive width.Materials and ManufacturingMechatronic Desig