grant-proposal-2009-2

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Towards robot assisted, rapid manufacturing in architecture
Preamble
In this application we ask for support to allow us to work towards robot assisted,
rapid manufacturing in architecture.
We hope to be able to continue to expand on ideas and practices that we have
worked on for over thirty years, and continue to learn from efforts at rationalizing
construction of large scale structures made throughout history.
To this end, we start in this document by giving a short over view of methods and
practices used to rationalize construction in history, ancient and recent.
In our future research we hope to focus on two methods of large-scale robotassisted rapid manufacturing techniques: the “pick and place” method, developed
by Gramazio and Kohler in Switzerland, and the “deposit and immobilize”
method, developed by d_Space in Italy.
Gramazio and Kohler have offered to collaborate with us; this will allow us to
benefit from their experience with the large scale robot at the ETH in Zurich as
well as their mobile robot, ROB.
In the “deposit and immobilize” field we have considerable experience at the
small scale through work methods using rapid prototyping of ice in our three year
research project “The architecture of phase change”. We hope to be able to
expand the scale of our structures through funding by FQRNT. A Cartesian robot
would complement our FAB@HOME robot, and our experience in path planning
at the small scale will scale up very well. The the main unresolved problem that
remains for large scale application is the method of deposition of material, which
will have to be scaled up from the micro valve water spray system (which we
developed, and which has worked very well at the small scale) to a larger scale
system. We hope to do this for large scale ice deposition as well as for other
materials.
First a small catalogue of material and labour saving strategies in architecture.
*Nubian Vaults
*McGill University Catenary Ice arch 1986
*Trulli : pseudo-vaults
*The Duomo, Florence
*Innu Igloos
*Gramazio and Kohler robotics
From placement of discrete elements to continuous flow methods: rapid
prototyping
Small scale rapid prototyping
*Examples of sculpture and medical, architectural, jewellery, and machine gears.
*Rapid prototyping using ice
Large scale rapid manufacturing
*D_Shape
In nature: termites and swallows are competent rapid prototypers!
Other examples of scaffolding-free large scale manufacturing of form
*Nylon-reinforced ice shells (water sprayed on nylon sheets under outdoor freezing
conditions)
*Shotcrete (or gunnite): cement-sand mix sprayed onto prepared rebar frame.
*Ferro-cement: Cement-sand mix mortared by hand on rebar-mesh form.
*Electro-chemical deposition of sea salts as a method to construct free-form architectural
elements.
Minimizing form work : the pise` method
*Illustration of the pise’ method
*Pantheon 1/5 full scale construction in snow
*Nubian vaults
In architecture there have been techniques for free-form, formwork-free
construction since the beginning of time. The Egyptian or Nubian vault is a good
example of this. Buildings are being roofed with single and double-curved
shapes constructed out of adobe bricks glued together with mud, using only
string guides as ‘form controllers’.
Catenary ice arch constructed from 2000 2 liter blocks at McGill University 1986
In Southern Italy the Trulli builders have built pseudo-vaulted structures of
manually laid horizontal layers of stone without using scaffolding for centuries:
In Florence stands to this day the double-shell dome of Santa Maria Della Fiore
constructed without any scaffolding by Bernini in 1453:
The method of interlacing thin tile bricks is shown below in a reconstruction:
The Innu in the arctic have used a formwork-free technique building their igloos,
using snow blocks and stacking and gluing them without formwork in spiral
fashion to form a double curved dome in a matter of hours.
Modern times
Scaffolfing-free techniques have in recent years been studied for their suitability
to robotic construction. Gramazio and Kohler at the ETH in Zurich have built a
reputation on the robotic manipulation of bricks in intricate patterns that have
been used in several real-world architectural and sculptural applications.
Continuous flow construction, using scaffolds
When using plastic building materials architects have traditionally used aggregate (generally
locally found gravel and sand) and a binder. The earliest builders used bitumen, the Romans
used pozzuolan, the Gothic builders in the middle ages used lime mortar and in modern times
we have used Portland cement as the binder of choice. All construction was based on casting
a binder-aggregate mix on wooden or steel reinforcing scaffolding.
Continuous flow construction without scaffold, at the small scale
Making 3 d objects or structures using continuous flow and without the support of a scaffold
has been possible at the small scale in recent years using robotic processes.
The small scale
The invention of 3D printing has opened up a new world of manufacturing of small, complicated,
intricate 3D objects.
Applications have been found in medical applications, architectural and models, and models of
sculptures, jewellery and machine parts.
Sculpture made by RP
Modeling of conjoined sculls
Architectural model
Jewellery made by rapid prototyping
Rapid Prototyped machine parts
3D Ice Twisted Koch fractal fabricated at McGill University
Cliff swallow nests: rapid prototyping using mud
Materials used in small-scale rapid prototyping
Materials used in these processes are variously extruded polymers, laser beam solidified liquid
polymers, fused/ sintered ceramics, and, at the University of Missouri and at McGill University, water
and ice.
Continuous deposition methods: Scaling up
In African Iron making, termite nests or parts thereof were used in
iron smelting since the invention of that technology in ancient history.
Expanding the layer by layer printing method to a larger scale is difficult for several reasons. The small
scale manufacturing is easily executed indoors, in controlled environments, while large scale production
has often to be done outdoors, and thus under variable conditions. Another problem is that the robotic
machinery to be used for larger scale operations is not readily available.
One company, D-Shape has started work on ‘architectural scale layered deposition manufacturing’, by
applying a binder through a computer controlled nozzle to thin layers of sand, laid down one after
another.
The set-up that is used by Dini is essentially an enlarged Fab@Home Cartesian robot; gantry models like
this are available ‘off the rack’
The surface finish that this method allows is quite smooth (after a bit of sanding!)
A large amount of ‘scaffolding sand’ will have to be removed, depending on the shape of the structure.
Large scale deposition method using snow and water in a freezing
environment
This method would lend itself well to the construction of a snow/ice building. By manually laying down
layers of say 1” of snow, covering that layer with a computer- generated, computer-cut schablone (or
mask) and spraying the exposed snow with water, and repeating this layer after layer. Removing the
outside form and the loose, not iced-up snow will reveal the intended structure (which will need some
minor sanding to smooth the contours.)
Here is a picture of what a snow/ice object might look like (the sculpture in the picture is in reality
carved from a solid mass of snow)
FREE FORM large scale methods before robots
The applicant of this grant has worked in free-form construction for many years:
Nylon reinforced 1” thick thin shell ice, McGill University 1973
“Nubian” Catenary Ice arch 1987, McGill University (this structure was not from work free)
30’ Hyperbolic Paraboloid 1” thick nylon-reinforced ice structure with scaffold-steel pipe edges.
McGill University 1986
The system of spraying water on a nylon mesh layer is very similar to the technique of shot crete or
gunnite, which blows ‘gunns’ a mortar mix with co pressed air against a rebar/mesh surface.
34’ span 1/5 scale model of the Roman Pantheon constructed at McGill University 1996 exterior
Interior of the Ice Pantheon. This building was constructed in the Pise method, and reached 34 feet
height and span.
Pise Method Illustrated
Pise method used for Ice Pantheon 1996
From the laboratory to the real world 1973-1975
3D in Ferro-cement
Design for a double-curved thin shell ferro cement play structure 1974
Rebar and mesh assembly in the McGill University Engineering Laboratory 1974
Finished Ferro-cement play structure after transportation to the site 1974
Site-Built ferro-cement play strcture. Montreal 1976
Ferro cement play structure under construction Montreal 1976
Electro-biological Accretion of Seawater minerals 1989 Barbados:
http://www.youtube.com/watch?v=oLa25RktKVo&feature=related
The grant applicant, worked for several years with Wolf Hilbertz who obtained patents to electrochemical deposition of sea salts on a conductive mesh substrate. The research consisted of trying to
build self-supporting roof channels to replace the asbestos-cement channels of “Canaletta model “
that were used world-wide but could no longer be made in that material because of the known dangers
of asbestos.
Links:
Thin shell construction in South Africa:
http://picasaweb.google.com/bellamyjk/BuildingInSouthAfrica/#
Ice RP University of Missouri:
http://web.mst.edu/~vrpl/proj-rp.htm
Contour Crafting at the University of Southern California at LA
http://www.contourcrafting.org/
MIT’s ill fated experimental freeform thin masonry vault experiment:
http://vaulting.wordpress.com/
The work of John Ochsendorf at MIT: http://web.mit.edu/newsoffice/2007/ochsendorf-0516.html
Thimbrell vaulting:
http://www.lowtechmagazine.com/2008/11/tiles-vaults.html
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