Hi, everyone, my name is Abdullah. I'm from the Hasso
Plattner Institute, and today I'm going to talk about fast
force. Let's look at an example case. Here we have a laser cut
wheelbarrow. Now when I tried to lift it up, the handles break
off. Fast force identifies this problem during the modeling
process, and generates appropriate reinforcements and
now the handles are 45 times stronger.
Recently, a good amount of progress has been made around
laser cutting systems that allow users to model in 3d such as
flat fab, or as we see here kyub the key benefit of kyub is that
it's designed to create things that are very, very strong. and
achieves that by making models based on what we call closed box
structures, which are held together by finger joints. This
is all good and fine. But as it turns out, some models require
additional reinforcement. For example, in the case of this
chair, the legs can be ripped out. So when we did the kyub
paper, we already acknowledge this and added a manual
reinforcement tool. In this case, you need to understand
that the legs will rip out and then use the tool to add an
additional plate. Now the big challenge is, and that's what my
work today is about. Can users recognize the problem. We also
did a small study during a workshop in which we asked
people to design guitar stands. And as it turns out, six out of
seven participants had produced structural issues without
recognizing them. So as a result, we say that the main
requirement of our work is that reinforcement should not be done
by the users, because they just don't know how to do it, it
should be done automatically by the system. And as a second
requirement, this should happen at interactive rates. And here's
why. I'm thinking about two guitar stands. I really like the
one on the left, but I'm unsure about the sturdiness of the
design. But with the right one, I'm more confident. Since I'm
unsure while designing, I would end up iterating on both
designs. But if I knew right away that both designs work out,
it allows me to choose the model I prefer immediately rather than
working on some backup model. So to find the structural issues,
we first tried to go to technique, finite element
analysis, and he got some results. For example, we now
know that a 10 Newtons to handle start to break. But the problem
is that finite element analysis in case of the wheelbarrow took
eight hours, which fails our second requirement. When we
classified all the issues that finite elements identified, we
found that not all cases are equally important. Some of these
only break under very high forces. But what we are really
interested in is a subclass of problems that breakaway earlier.
So we approach the problem in three steps. First, we manually
classified the points of failure. Here's simplification
of the wheelbarrow handles, we call this case E1 because it's
an extrusion connected to one side, and if you can bend it in
the indicated direction, it will break. And there are other
cases. Here the extrusion is connected from two sides, or it
is completely disconnected. The important thing is that all of
these points of failure fall into the category of extrusions
that can be broken on the opposite form cavities that can
be pushed in. Number two, we devise multiple ways to
reinforce all the points of failure. For example, in this
case, to reinforce this point of failure, we need to have at
least two parallel plates connecting the extrusion because
that's what makes it structurally strong. And number
three, we wrote a software algorithm fast forward that both
identifies these points of failure and reinforces them in
real time. Fast force uses a graph representation to look for
connectivity problems. First, it removes all the joints where
tension can be applied. This results in disconnected sub
graphs, which point to parts in the object which can fall apart
very easily. Next, we look for weakly connected parts in the
model by performing node cuts here at one node cut indicates
that the handles can rip off while the two node cut tells us
that the legs can break. After identifying all the issues
fast force reinforces them starting with the weakest points
of failure to stop the tray from falling in the bottom plate
is extended and anchored into the sides of the wheelbarrow
to stop the legs from being pulled out. Fast forward chooses
two parallel plates and extends them into the body. The handle
and the back legs are reinforced in a similar way. We also tested
the structural strength of the points of failure and
we measured 3 to 50 time gains in strength. We
also looked at the performance of our system. And we see that
even with complex models which have reasonable number of nodes
fast force can provide analysis at interactive rates. Based
on these results, we integrated fast force into
an interactive editor. Here we see the user modeling the wheelbarrow
in kyub. And as you can see as soon as a weakness
appears during modeling fast force immediately generates
a reinforcement. And this continues during the course
of the modeling process
The main takeaway is that with manual reinforcement, we limit
laser cutting to people with knowledge of structural
engineering, but with our system fast force, since it has
automatic reinforcement, we can bring laser cutting to people
without a background in structural engineering and
enable them to create sturdy objects. Thank you for your
time, and I look forward to your questions.