259 research outputs found
A level set based method for fixing overhangs in 3D printing
3D printers based on the Fused Decomposition Modeling create objects
layer-by-layer dropping fused material. As a consequence, strong overhangs
cannot be printed because the new-come material does not find a suitable
support over the last deposed layer. In these cases, one can add some support
structures (scaffolds) which make the object printable, to be removed at the
end. In this paper we propose a level set method to create object-dependent
support structures, specifically conceived to reduce both the amount of
additional material and the printing time. We also review some open problems
about 3D printing which can be of interests for the mathematical community
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
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
Chopper: Partitioning models into 3D-printable parts
3D printing technology is rapidly maturing and becoming ubiquitous. One of the remaining obstacles to wide-scale adoption is that the object to be printed must fit into the working volume of the 3D printer. We propose a framework, called Chopper, to decompose a large 3D object into smaller parts so that each part fits into the printing volume. These parts can then be assembled to form the original object. We formulate a number of desirable criteria for the partition, including assemblability, having few components, unobtrusiveness of the seams, and structural soundness. Chopper optimizes these criteria and generates a partition either automatically or with user guidance. Our prototype outputs the final decomposed parts with customized connectors on the interfaces. We demonstrate the effectiveness of Chopper on a variety of non-trivial real-world objects.National Science Foundation (U.S.) (Grant CCF-1012147)National Science Foundation (U.S.) (Grant IIS-1116296)Intel Corporation (Science and Technology Center for Visual Computing
PAVEL: Decorative Patterns with Packed Volumetric Elements
Many real-world hand-crafted objects are decorated with elements that are
packed onto the object's surface and deformed to cover it as much as possible.
Examples are artisanal ceramics and metal jewelry. Inspired by these objects,
we present a method to enrich surfaces with packed volumetric decorations. Our
algorithm works by first determining the locations in which to add the
decorative elements and then removing the non-physical overlap between them
while preserving the decoration volume. For the placement, we support several
strategies depending on the desired overall motif. To remove the overlap, we
use an approach based on implicit deformable models creating the qualitative
effect of plastic warping while avoiding expensive and hard-to-control physical
simulations. Our decorative elements can be used to enhance virtual surfaces,
as well as 3D-printed pieces, by assembling the decorations onto real-surfaces
to obtain tangible reproductions.Comment: 11 page
Slice and Dice: A Physicalization Workflow for Anatomical Edutainment
During the last decades, anatomy has become an interesting topic in
education---even for laymen or schoolchildren. As medical imaging techniques
become increasingly sophisticated, virtual anatomical education applications
have emerged. Still, anatomical models are often preferred, as they facilitate
3D localization of anatomical structures. Recently, data physicalizations
(i.e., physical visualizations) have proven to be effective and
engaging---sometimes, even more than their virtual counterparts. So far,
medical data physicalizations involve mainly 3D printing, which is still
expensive and cumbersome. We investigate alternative forms of physicalizations,
which use readily available technologies (home printers) and inexpensive
materials (paper or semi-transparent films) to generate crafts for anatomical
edutainment. To the best of our knowledge, this is the first computer-generated
crafting approach within an anatomical edutainment context. Our approach
follows a cost-effective, simple, and easy-to-employ workflow, resulting in
assemblable data sculptures (i.e., semi-transparent sliceforms). It primarily
supports volumetric data (such as CT or MRI), but mesh data can also be
imported. An octree slices the imported volume and an optimization step
simplifies the slice configuration, proposing the optimal order for easy
assembly. A packing algorithm places the resulting slices with their labels,
annotations, and assembly instructions on a paper or transparent film of
user-selected size, to be printed, assembled into a sliceform, and explored. We
conducted two user studies to assess our approach, demonstrating that it is an
initial positive step towards the successful creation of interactive and
engaging anatomical physicalizations
Screwing assembly oriented interactive model segmentation in HMD VR environment
© 2019 John Wiley & Sons, Ltd. Although different approaches of segmenting and assembling geometric models for 3D printing have been proposed, it is difficult to find any research studies, which investigate model segmentation and assembly in head-mounted display (HMD) virtual reality (VR) environments for 3D printing. In this work, we propose a novel and interactive segmentation method for screwing assembly in the environments to tackle this problem. Our approach divides a large model into semantic parts with a screwing interface for repeated tight assembly. Specifically, after a user places the cutting interface, our algorithm computes the bounding box of the current part automatically for subsequent multicomponent semantic Boolean segmentations. Afterwards, the bolt is positioned with an improved K3M image thinning algorithm and is used for merging paired components with union and subtraction Boolean operations respectively. Moreover, we introduce a swept Boolean-based rotation collision detection and location method to guarantee a collision-free screwing assembly. Experiments show that our approach provides a new interactive multicomponent semantic segmentation tool that supports not only repeated installation and disassembly but also tight and aligned assembly
An overview of some mathematical techniques and problems linking 3D vision to 3D printing
Computer Vision and 3D printing have rapidly evolved in the last 10 years but
interactions among them have been very limited so far, despite the fact that
they share several mathematical techniques. We try to fill the gap presenting
an overview of some techniques for Shape-from-Shading problems as well as for
3D printing with an emphasis on the approaches based on nonlinear partial
differential equations and optimization. We also sketch possible couplings to
complete the process of object manufacturing starting from one or more images
of the object and ending with its final 3D print. We will give some practical
examples of this procedure
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