INTERACTIONS.ACM.ORG 78 INTERACTIONS SEPTEMBER–OCTOBER2017
FORUM INTERACTION TECHNOLOGIES
allow for faster iteration, low-fidelity
fabrication [ 4] can print intermediate
versions of a design as fast as low-fidelity versions. Only the final version
will be printed as slow high-fidelity.
The low-fidelity version preserves
the key aspect that is currently being
tested, such as the shape of an object
(see Figure 2, WirePrint [ 4]). Figure
2 also shows faBrickation [ 5], another
implementation of the low-fidelity
fabrication concept that focuses on
modularity by combining off-the-shelf
Lego bricks with 3D-printed parts.
Interaction model. Researchers have
also questioned whether the current
interaction model with 3D printers
in which users use a digital editor to
create a physical object is the best
workflow. With interactive fabrication
[ 6], researchers have instead proposed
that users work hands on with the
physical workpiece, as in traditional
crafting, providing physical feedback
after every editing step. Figure 3 (left)
shows such a system: Users touch the
screen and see the physical output in
the form of foam drops as they appear
on the platform underneath after a few
seconds. Because fast physical output
is challenging, researchers have also
built intermediate systems toward
this vision based on augmented and
mixed reality (e.g., MixFab [ 7], shown
in Figure 3).
Optional: finishing and post-coloring. To give the object a higher-quality appearance, finishing can be
applied to the 3D-printed objects.
Depending on the material and
process used, different finishing
steps are suitable, such as using
sandpaper or acetone to smooth the
surface. Besides polishing the surface,
additional color can be added, for
instance, via hydrographic printing, in
which the object is dipped into a water
bath with a custom-color film floating
on its surface that subsequently
adheres to the object.
Despite the amazing potential of 3D
printing technologies, there remain
some sticky problems that must be
solved. Here are some of the key
challenges we face in the coming
Speed. One challenge with 3D
printing is that the process is relatively
slow. For instance, printing an object
the size of a head-mounted display
takes around 15 hours on a plastic
extrusion printer. When designing
a new object that requires many
iterations, the long fabrication time
slows down the design process. To
with 3D printing is
that the process
is relatively slow.
Figure 1. 3D printing with different materials: (left) a 3D-printed soft teddy bear [ 2]; (right) a
3D-printed glass vase [ 3].
Figure 2. Two low-fidelity fabrication techniques that save hours of printing time: (left)
WirePrint [ 4] and (right) faBrickation [ 5].
Figure 3. (left) Interactive fabrication with Shaper [ 6]. (right) MixFab: a mixed-reality modeling
environment that allows users to embed real-world objects [ 7].
Figure 4. Patching Physical Objects [ 8] allows
users to change existing physical objects to
minimize waste and printing material.