41,561 research outputs found
Construction of scale models in industrial design: the irruption of additive manufacturing. Rubrics proposal for an objective evaluation
Comunicació presentada a EDULEARN2019, 11th International Conference on Education and New Learning Technologies (July 1-3, 2019, Palma, Mallorca, Spain).Recent studies corroborate the progressive implementation of Additive Manufacturing technologies (commonly known as 3D printing) in education, demonstrating several advantages. In the field of industrial design, the development of models during the design phase of product design helps designers in training to visualize their proposals. Today, 3D printing and traditional model-making techniques coexist in classrooms. With both techniques it is possible to achieve good results, but when it comes to evaluating them it is not so simple, since both ways of working are different and apparently the same evaluation criteria cannot be used in both cases, which could lead to comparative grievances.
This work presents a series of rubrics that can help to evaluate the student's models in an objective way and under equal conditions, independently of the technique used: traditional o 3D printing. In order to do this, we started from a rubric made to evaluate traditional models, which was tested during a couple of academic years in other subject. This rubric was adapted to create a new rubric, which allowed to evaluate models made by 3D printing, looking for equivalent criteria with the previous rubric to guarantee a fair evaluation of both ways of working.
The rubrics were tested experimentally in the subject ‘Prototypes: experimental workshop’, taught during the 4th year of the Bachelor's Degree in Industrial Design and Product Development Engineering at the Universitat Jaume I (Spain). Two groups of users assessed each work using these rubrics. The results showed, on the one hand, that both groups found it easy to evaluate the works using these rubrics, and on the other hand, that these rubrics allow for a fairly objective evaluation of the works, since the score obtained by both groups of users was very similar
Survey on Additive Manufacturing, Cloud 3D Printing and Services
Cloud Manufacturing (CM) is the concept of using manufacturing resources in a
service oriented way over the Internet. Recent developments in Additive
Manufacturing (AM) are making it possible to utilise resources ad-hoc as
replacement for traditional manufacturing resources in case of spontaneous
problems in the established manufacturing processes. In order to be of use in
these scenarios the AM resources must adhere to a strict principle of
transparency and service composition in adherence to the Cloud Computing (CC)
paradigm. With this review we provide an overview over CM, AM and relevant
domains as well as present the historical development of scientific research in
these fields, starting from 2002. Part of this work is also a meta-review on
the domain to further detail its development and structure
Digital design of medical replicas via desktop systems: shape evaluation of colon parts
In this paper, we aim at providing results concerning the application of desktop systems for rapid prototyping of medical replicas
that involve complex shapes, as, for example, folds of a colon. Medical replicas may assist preoperative planning or tutoring in
surgery to better understand the interaction among pathology and organs. Major goals of the paper concern with guiding the
digital design workflow of the replicas and understanding their final performance, according to the requirements asked by the
medics (shape accuracy, capability of seeing both inner and outer details, and support and possible interfacing with other organs).
In particular, after the analysis of these requirements, we apply digital design for colon replicas, adopting two desktop systems. ,e
experimental results confirm that the proposed preprocessing strategy is able to conduct to the manufacturing of colon replicas
divided in self-supporting segments, minimizing the supports during printing. ,is allows also to reach an acceptable level of final
quality, according to the request of having a 3D presurgery overview of the problems. ,ese replicas are compared through reverse
engineering acquisitions made by a structured-light system, to assess the achieved shape and dimensional accuracy. Final results
demonstrate that low-cost desktop systems, coupled with proper strategy of preprocessing, may have shape deviation in the range
of ±1 mm, good for physical manipulations during medical diagnosis and explanation
From 3D Models to 3D Prints: an Overview of the Processing Pipeline
Due to the wide diffusion of 3D printing technologies, geometric algorithms
for Additive Manufacturing are being invented at an impressive speed. Each
single step, in particular along the Process Planning pipeline, can now count
on dozens of methods that prepare the 3D model for fabrication, while analysing
and optimizing geometry and machine instructions for various objectives. This
report provides a classification of this huge state of the art, and elicits the
relation between each single algorithm and a list of desirable objectives
during Process Planning. The objectives themselves are listed and discussed,
along with possible needs for tradeoffs. Additive Manufacturing technologies
are broadly categorized to explicitly relate classes of devices and supported
features. Finally, this report offers an analysis of the state of the art while
discussing open and challenging problems from both an academic and an
industrial perspective.Comment: European Union (EU); Horizon 2020; H2020-FoF-2015; RIA - Research and
Innovation action; Grant agreement N. 68044
Pushing the Limits of 3D Color Printing: Error Diffusion with Translucent Materials
Accurate color reproduction is important in many applications of 3D printing,
from design prototypes to 3D color copies or portraits. Although full color is
available via other technologies, multi-jet printers have greater potential for
graphical 3D printing, in terms of reproducing complex appearance properties.
However, to date these printers cannot produce full color, and doing so poses
substantial technical challenges, from the shear amount of data to the
translucency of the available color materials. In this paper, we propose an
error diffusion halftoning approach to achieve full color with multi-jet
printers, which operates on multiple isosurfaces or layers within the object.
We propose a novel traversal algorithm for voxel surfaces, which allows the
transfer of existing error diffusion algorithms from 2D printing. The resulting
prints faithfully reproduce colors, color gradients and fine-scale details.Comment: 15 pages, 14 figures; includes supplemental figure
Influence of Print Orientation on Surface Roughness in Fused Deposition Modeling (FDM) Processes
In the present paper, we address the influence of print orientation angle on surface roughnessobtained in lateral walls in fused deposition modelling (FDM) processes. A geometrical model isdefined that considers the shape of the filaments after deposition, in order to define a theoreticalroughness profile, for a certain print orientation angle. Different angles were considered between 5¿and 85¿. Simulated arithmetical mean height of the roughness profile, Ra values, were calculated fromthe simulated profiles. The Ra simulated results were compared to the experimental results, whichwere carried out with cylindrical PLA (polylactic acid) samples. The simulated Ra values were similarto the experimental values, except for high angles above 80¿, where experimental roughness decreasedwhile simulated roughness was still high. Low print orientation angles show regular profiles withrounded peaks and sharp values. At a print orientation angle of 85¿, the shape of the profile changeswith respect to lower angles, showing a gap between adjacent peaks. At 90¿, both simulated andexperimental roughness values would be close to zero, because the measurement direction is parallelto the layer orientation. Other roughness parameters were also measured: maximum height ofprofile, Rz, kurtosis, Rku, skewness, Rsk, and mean width of the profile elements, Rsm. At high printorientation angles, Rz decreases, Rku shifts to positive, Rsk slightly increases, and Rsk decreases,showing the change in the shape of the roughness profiles.Postprint (published version
Computer-aided position planning of miniplates to treat facial bone defects
In this contribution, a software system for computer-aided position planning
of miniplates to treat facial bone defects is proposed. The intra-operatively
used bone plates have to be passively adapted on the underlying bone contours
for adequate bone fragment stabilization. However, this procedure can lead to
frequent intra-operatively performed material readjustments especially in
complex surgical cases. Our approach is able to fit a selection of common
implant models on the surgeon's desired position in a 3D computer model. This
happens with respect to the surrounding anatomical structures, always including
the possibility of adjusting both the direction and the position of the used
osteosynthesis material. By using the proposed software, surgeons are able to
pre-plan the out coming implant in its form and morphology with the aid of a
computer-visualized model within a few minutes. Further, the resulting model
can be stored in STL file format, the commonly used format for 3D printing.
Using this technology, surgeons are able to print the virtual generated
implant, or create an individually designed bending tool. This method leads to
adapted osteosynthesis materials according to the surrounding anatomy and
requires further a minimum amount of money and time.Comment: 19 pages, 13 Figures, 2 Table
Towards Zero-Waste Furniture Design
In traditional design, shapes are first conceived, and then fabricated. While
this decoupling simplifies the design process, it can result in inefficient
material usage, especially where off-cut pieces are hard to reuse. The
designer, in absence of explicit feedback on material usage remains helpless to
effectively adapt the design -- even though design variabilities exist. In this
paper, we investigate {\em waste minimizing furniture design} wherein based on
the current design, the user is presented with design variations that result in
more effective usage of materials. Technically, we dynamically analyze material
space layout to determine {\em which} parts to change and {\em how}, while
maintaining original design intent specified in the form of design constraints.
We evaluate the approach on simple and complex furniture design scenarios, and
demonstrate effective material usage that is difficult, if not impossible, to
achieve without computational support
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