The Super Powers of Wood Buildings That Shape Themselves
[Music]
today we’re going to talk
about shape so shape is everywhere
around us
and what you might not realize is how
the things that we use
every day are actually shaped things
like the seat of your chair
are produced by by pulling and pushing
on the materials
with giant hydraulic presses to fit
exactly to the contours of your body
and when it comes to shape some of the
largest things that we need to shape
are for our buildings in architecture
shape gives us form and structure
and it creates the things in which we
inhabit every day
so let’s first talk about a building
here in stuttgart
so this is a really controversial
building
but i like it i love the architectural
features
the way that the light can enter from
above and most of all i really like the
geometry
it’s smooth and elegant but what i don’t
like about this building
is how it’s made because well as
architects we’ve developed digital
processes to optimize our models on the
screen
and robotically produce the parts which
make up each piece of our building
the way in which we physically do it is
still i would argue
backwards so for these columns for
example we actually have to build them
three times first we build them from
steel
to form reinforcement and it needs to be
shaped every single piece of steel
then we build it from wood solid wood
in order to form a formwork in which we
can finally
pour the concrete which will form the
final piece
and in developing these processes
they’ve become complex
and involves supply chains that reach
around the globe
what’s clear is that despite our
advances
we still rely on very basic processes
in order to create the shapes
and the problem with this is that they
eat up tons of energy and material
and bought in wuttenberg for example by
some recent estimates
the construction industry alone
contributes over 50
of the material waste for everything
that we use
and when we think about carbon and
embedded energy
we often think about things like flying
less
or riding our bike to work or making our
cars more efficient
but what we really should think about is
the fact that buildings alone
contribute dramatically more to the
problems of sustainability
than transport or other aspects
and when we try to solve these problems
we generally try to go more high-tech
we think about how robots can make
things more efficient and processes can
become
more precise but in the end we still
rely
on brute force methods to form and shape
our materials
for example we carve things with higher
force and more precision
or we bend pull or push our materials
into shape
and this just becomes a larger and
larger problem as things get bigger
the robots have to become bigger
and in many cases you might say that we
even rely on aggressive processes
where the materials play a completely
passive role
in the final components in which they
might become
so now let’s imagine a different way of
generating shape
so we’re in a forest with trees around
us and the light coming in from above
and it’s completely silent and in this
forest there’s shaping happening all
around us
all the time and i’m not talking about
living trees
or growing things what i’m talking about
are things like pine cones or seed pods
and what these what these pine cones are
able to do is that the scales
on the side of the cone are actually
able to change their shape
in changes with relative humidity in the
air and this means that a pine cone can
can remain closed when it needs to
protect its seeds
and open up only when it’s dry enough at
the precisely the right moment
in order to release its seeds now what’s
amazing about this
is it happens in millions of pinecones
all around the world
and it does so not by a machine or a
computer
or a microcontroller or any sort of
sensor
it does so because the hydroscopic
fibers that are laid
inside of its its skin
and when these fibers get wet they
expand and when they dry
they shrink and what’s even more
astounding
is that this process happens after the
pinecone has been cut off
from the supplies of the tree so there’s
also no living energy involved
and what this means is that even a pine
cone that’s 12 million
years old and fossilized when we take it
out
and put it in water or dry it out it
still retains the ability to change
shape now i absolutely love
robots and i love computers
but i have to say that when i see how
simply the pinecone works
and how well it works in order to
generate shape i have to say
that even after 12 years i would still
rely on the pine cone over a robot
now our goal here is to see how
if the pine cone can generate shapes so
smoothly and so fluidly
we can actually use a similar approach
to shape the way we build our buildings
and to do that we use a really high-tech
material any ideas
we use wood so wood is one of the most
abundant natural resources
on our planet and the best part of all
is that it regenerates
it comes back if we plant more trees and
we’re planting more and more trees
now what is involved in the construction
industry for hundreds of years
but what you might not know about wood
is that just like the pine cone
it has this strange ability to change
shape when it gets wet
and when it dries and this is something
that has caused problems
for many many years and scientists have
struggled to figure out ways in order to
keep our walls
not from moving but
at the same time if you really look at
the wood the forces inside of it are so
strong that it can rip itself apart the
forces are so powerful
that ancient greeks use them to split
granite blocks from their quarries
so what we want to do is see how we can
harness this force in wood
to generate design shapes that we want
for our buildings and in my group at the
university of stuttgart
we call this concept material
programming because
similar to how we can program movement
in robots digitally
we think we can also physically arrange
materials in a way in which they
generate shape
themselves
so to do so in our first studies we
looked at how we could take apart a tree
trunk
in the fewest amount of steps possible
and rearrange it into a really nice
shape
without using any mold to do this
it’s pretty simple we basically build a
giant puzzle
so we take apart the wood we put it into
small triangles and then we
rearrange it but each triangle has a
specific direction and this determines
how it will change shape
here we use beechwood a wood that my
grandfather likely would have split
up and used as firewood precisely
because it’s going to change into
strange shapes so it’s not so good for
anything else
but here once we have this flat sheet
all we have to do is add water
and slowly the shape emerges
and in the same way again by removing
the water
we can reverse the effect
now this might seem like a small art
project or something for a bit of fun we
can make a piece of wood change shape
because these pieces are pretty small
and we could imagine shaping them with
our hands or with a few tools
but when we imagine shaping something
the size of a wall
or a column then it becomes hard to
imagine how we might do it or even a
robot might do this
effectively and that’s where we start to
look at how we can upscale this process
to do so we have to do two things first
we have to be able to precisely predict
the change in shape
and this is where our computational
design tools come in
because with these tools we can do this
much more accurately than we’ve ever
been
able to do before the second thing is
that we needed to stop
changing shape when we want to use it in
our building and that will come to later
so the production of these types of
pieces begins like any normal sawmill we
have to first cut the logs
into boards and here we use freshly cut
spruce wood which starts with a
relatively high moisture content
just when it comes from the tree then we
combine these boards into two ply layups
which we call bi layers
these are five meter long really serious
pieces of wood
and when we put these bilayers into a
kiln we can dry them out
and inside the shape emerges completely
autonomously
smoothly and coordinated all at the same
time
in a giant piece of wood after which we
can take these bilayers that are then
curved
all to the same curvature and we can
combine them to form bigger components
for our building
and by layering two of them together and
connecting them
we therefore stop the change in shape
meaning that we have a form stable
component then all we have to do
is slightly trim the edges to add some
detailing so that we can connect them
later
we use these thin high curvature pieces
in order
to build a tower structure the tower
cantilevers 14 meters into the sky
yet it’s built from just 90 millimeter
thick clt
on the interior the curvature gives the
wood an entirely new
architectural and spatial expression
it’s not something that we’ve seen
before
the curvature is soft almost like a
pillow
and it’s friendly to touch
and the best part of this is that we’re
able to do this in a way that is
elegantly designed
ecological and efficient
it just makes sense
now on the other side of the scale we
can think about smaller pieces and we
can think about how our buildings
operate every day we open and close our
windows
or we have an automated shading system
and for many years our group in the
university of stuttgart has been
studying how we could actually use the
change in shape in wood
in smaller veneer pieces to build
systems that operate in relation to the
outside environment
to do so we use very thin pieces of wood
that respond
cyclically this means we can create
systems
that open for example when it’s sunny
and then automatically
close up when the rain is approaching
but there are some limitations with
using wood in this way
it can only bend a certain way because
it has this beautiful
natural structure so in our more recent
work
we look at how we can break down certain
parts of the wood
and turn these into materials that we
can then use 3d printing to arrange in
very specific patterns
this means we can give wood a new
function we can allow it to bend
it can be flexible and it can be porous
and through doing so we can create an
entirely new generation
of shape-changing mechanisms mechanisms
that are soft
but still use the power of wood
and like the pinecone these things can
operate
over and over again reliably
they just happen to work there’s no
trick there’s no
machine and there’s no computer
so in the future i think we will build
buildings not with machines but by
cleverly understanding the way in which
materials work
the very materials that they’re made of
and it’s my hope
that by doing so we can build more
ecologically
smarter higher faster and best of all
silently thank you