MatWorks Master thesis Martin Firera Alessandri
MatWorks Multi-Material Matters - research of a site-specific additive multimaterial building process
Martin Firera I Julian Hildebrand I Ohad Meyuhas I Jordi Portell I - Iaac - studio of digital tectonics 2010-2011 - Marta Male Alemany, Victor Vi単a, Brian Peters
MatWorks Multi-Material Matters - research of a site-specific additive multimaterial building process
Martin Firera I Julian Hildebrand I Ohad Meyuhas I Jordi Portell I - Iaac - studio of digital tectonics 2010-2011 - Marta Male Alemany, Victor Vi単a, Brian Peters
Martin Firera Julian Hildebrand Ohad Meyuhas Jordi Portell
Italy Germany Israel Spain
MAA 2010-2011 studio of digital tectonics
Marta Male-Alemany, Victor Vi単a, Brian Peters
01 Introduction 01.1 Studio brief - (FAB)BOTS 2.0 01.2 Thesis 01.3 Inspiration from previous research
02 Material experiments 02.1 Paper 02.2 Granular material
P 11 P 12 P 13
08 08.1 08.2 08.3
P 16-19 P 20-21
09 09.1 09.2 09.3
03 New ways of building 03.1 Styrofoam Dome 03.2 Tao Earth House
P 24 P 25
04 04.1 04.2 04.3
Rapid prototyping Selective Laser Sintering (SLS) Fused Deposition Modelling (FDM) Stereolitography (SLA)
P 28 P 29 P 30 P 31
05 05.1 05.2
Intelligent material networks Physical performance Following nature’s example
P 34-35 P 36-37
06 06.2 06.3 06.4 06.5 06.6
Material treatment Relation between layer thickness and penetration depth in hardening process Sequence of deposition and Layering Material network and material removal Manually controlled deposition of a complete material network Material interactions
P 40 P 41-43 P 44-45 P 46-47 P 48-51
07 07.1 07.2 07.3 07.4 07.5 07.6 07.7 07.8
Simulation Solvent SandBox-2D Sand machine SandBox-3D SandBox-3D user manual Communication with the shopbot Granular material samples Creation of material channels
P 54 P 54 P 55 P 56-57 P 58 P 59 P 60-63 P 64-65
Machinic prototypes Nozzle prototype of linear array Hacking the shopbot milling machine Improved nozzle
Digital control Material layers Digitally controlled deposition of a complete material network Material removal through air pressure (Erosion through wind turbulence) 09.4 Creation of ducts within the network
P 68 P 68-69 P 70-71
P 74-75 P 76-77 P 78 P 79-81
10 Autonomous deposition device 10.1 First prototype 10.2 Prototype update 10.3 The final device
P 84-85 P 86-87 P 88-89
11 11.1 11.2 11.3 11.4 11.5
P 92-93 P 94 P 95-97 P 98-99 P 100-101
The building device on site The site The device Site Engineering Sequential built-up Possibilities of machinic movement
12 12.1 12.2 13
Simulation of machinic movement path Genetic Algorithm Machinic movement Conclusions and comments
P 104-105 P 106-107 P 108-109
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The team
P 110-111
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Literature and links
P 112-113
01 Introduction
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01.1 Studio brief - (FAB)BOTS 2.0 Continuing on the research from last year, the Digital Tectonics Research Studio 2010-11 will investigate the workflow between computational design and material production methods, exploring the relationship between design inputs and computer programmable devices that can be used for the production of building structures and or components. Challenging the traditional norms of linear file-to-factory production processes, the studio will examine scenarios in which parametric design and material production are developed simultaneously, exploring the potentials of linking design programming and machinic behaviour in real time. With support tutorials and exercises focusing on the creation of custom designed innovative hardware devices that incorporate sensory inputs and stepper motor control, the studio aims to propose alternatives to existing methods of digital fabrication to be deployed on-site. As these fabrication devices will enable a direct response to sensory inputs, systems of behavioural rules can be considered to influence the method of creating building elements or structures. Rather than scripting geometrical patterns of formation as in traditional uses of digital fabrication, behavioural rule systems can be used to direct machinic fabrication towards certain performance criteria scenarios, thus generating emergent material configurations that are not guided from a preconceived design. Using a setup consisting of design scripts, machine programming, a custom designed fabrication device and specific method of material formation, students teams will choreograph the creation of material structures that demonstrate that their formation has been influenced by external inputs like sound, light, temperature etc. Specific concerns in particular, this year the work will focus on how locality allows for hyper specific outcomes, as
the variables of the specific context (temperature, solar exposure, prevailing winds, etc.) are simultaneously embedded and recorded in the material result. Considering that the production process is dependent on external factors on site, recorded data will be physically translated and materialized in outcomes that contain both programmed design intentions and information from the environment. As such, material formations will be emergent and ‘harvested’ from the context. Moreover, the studio will emphasize the global preoccupation with dwindling energy resources by thinking about alternative production methods, such us the ones used prior to the industrial revolution (whether human or animal power, water or wind power). By raising awareness on this topic when it comes to new fabrication technologies, students will be encouraged to develop off -grid solutions, drawing inspiration from minimal-energy concepts like ‘perpetual motion machines’, which describe hypothetical apparatuses that operate or produce useful work indefinitely, or, more generally, machines that produce more work or energy than they consume. The projects will explore how today, through the application of digital technologies, we have the tools to engage with the environment for production, in a much more sustainable approach. Media & Methods: Hardware and As the processes of development will be as important as the demonstration of a working fabrication system, teams will be asked to present their entire process through photography, videos and diagrams explaining the working of scripts, hardware etc. The final result of the studio will be an A4 booklet and a DVD documenting design development and fi nal setup of the specific devices and their outputs
MAA 2010 2011
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01.2 Thesis Nowadays ,construction of buildings made of any kind of artificial stone such as concrete require an excessive amount of form work which most frequently is made of wooden panels or other materials such as steel or plastic. Considering that only a minor part of the material can be reused, manufacturing this form work, is a very time- and cotconsuming process; While 3-D printing technologies are advancing in fields of industrial design and rapid prototyping architectural applications using these technics at a building scale are still very rare and so far strictly limited to the use of one singular material. Even though prefabrication of entire building parts is already very developed and entire walls can be manufactured including insulation and ducts for water and electricity there is not yet any application out there which is able to combine the advantages of an architecture oriented 3-D printing process with the possibility of including the complete technical infrastructure required in a building by printing the whole architectural element including all ducts layer by layer through a multi-material process. MEP services are still considered as an add-on application in architecture. Our project starts here; with the intention to use as much as possible local material resources we intend to develop a 3-D printing process which using multiple materials with different physical properties ( structural, support, insulating, dissolving ) will deposit granular material in piles creating step by step and layer by layer a material network, i.e. a wall or any other building part which by the way it is built up may perform according to environmental requirements. This building process is supposed to happen machinically in an environmental feedback process. The outcome of this research may be a simple igloo-like building type with an intelligently composed skin which is able to perform well in an arid environment such as desert of Juda, our project site.
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http://www.imj.org.il/images/news/all/10/members5-large.jpg Shrine of the Book, Museum Israel, Jerusalem
Use of excessive form work in conventional building practice
http://www.behance.net/gallery/Sheikh-Zayed-Desert-Learning-Centre/723852 - Sheikh Zayed Desert Learning Centre, Chalabi Architects, Vienna
01.3 Inspiration from previous research The previously mentioned project called“ hosmenos” from DRL AA under the guidance of Marta Male-Alemany which indeed investigates on deposition of multiple granular materials has given us a perfect starting point for our research on a multimaterial printing process. This project furthermore researches some of the possibilities of using the properties of soluble ( decaying ) and dissoluble ( permanent ) granular materials to generate intersecting spacial configurations at a model scale. While this work already covers a wide range of material and geometric tests we realized that the process of material deposition could be taken further with the aim of moving the research focus from a model to a 1:1 scale and enhancing the control of material interaction in 3-dimensional space within the “printed” structure through a contemporary process of deposition.
“hosmenos” by Maria Eugenia Diaz Diaz, Kai Sun Lean, Alan McLean, Daniel Silverman Serra at DRL AA studio of Marta Male Alemany
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02 Material experiments
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02 Material experiments 02.1 Paper: Paper is a widely diffused material in an urban context, it can be shaped and moulded almost without limitation as long as it still contains enough water and is in a pasty state and it can be folded and be used almost similar to wood if only enough material layers are combined; for these reasons we started a wide range of tests with paper during the process of defining the scope of our studio project. In the first phase we tried different ways of making paper ourselves using blended newspaper, wood, soil , saw dust, various artificial glues and flour or linen oil as a natural glue as basic materials to be combined in a final recipe to allow us to produce a variety of paper qualities which vary in strength and flexibility. We realized soon that even without using any binder the paper fibres could be easily recombined by creating a paste a finally squeezing all water out. After the drying process we would end up with a rough, but quite flexible sheet of greyish paper; in adding flour as a binder we were able to harden the paper sheet which depending on the pressure applied during the removal of the water could be worked into an about 1 mm thick stiff sheet. Combined with a moulding process these sheets could be formed into various shapes. By varying the quantity of added flour we could further accelerate the hardening process and also the final stiffness and strength of the sheet. In combination with linen oil instead we produced a semiliquid paste which we deposited with a syringe in order to test an additive printing process with paper; We saw that with proceeding evaporation of the oil the deposited paste would shrink a lot which would make the control of the process quite difficult. Some test even included the integration of aluminium wires in the paper sheet in order to enable the material to conduct electricity.
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The red LED on the right hand image shows the positive result of this test. Very soon we decided that we wanted to keep all ingredients of the recipe biodegradable in order to make use of the hydrophilic properties of paper, thus we began to think that by creating different paper qualities which would vary in strength and consistence these papers would also decay at different speeds; on the other hand we also thought of integrating growth as a factor to define the project as an interaction of materials with not only different life spans, but also the capability to introduce life though growth into the system. For this reason we integrated seeds in some of the test modules done with paper and later also with a mixture of soil and wood.
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The idea of a multi-material process was born, even if that process was still going to change with the development of the thesis. While we made the first sheets by hand we soon wanted to test what kind of machine could be used to press the blended paper paste into a sheet and prepare it for moulding. The sketch on the left and the respective images show two simple hand-driven mechanisms. In the following test with the prototypes we had to realize that the high percentage of water involved in the process would inevitably lead to shrinking in the drying process and therefore make it difficult to have full control over to final result. Therefore we decided to test the potential of industrial paper available as sheets or coils as an alternative strategy.
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The ancient art of origami offers many fantastic examples of the sophisticated details that can be achieved using folding techniques in combination with paper. Our manual tests in this field made it clear that the most difficult task is not making the fold itself but rather working out the high and low points of the provided folds afterwards. While this task is already quite demanding by hand in a context of several modules it seamed finally too complicated for a machinic process. Techniques using a combination of cutting and folding as it is applied already by “robofold� produce accurate results for single module systems, but they require a well defined preconceived folding strategy which is not part of the concept of emergence desired in the project.
http://spacesymmetrystructure.wordpress.com/2009/03/24/origami-electromagnetism/
http://www.robofold.com/index.php?WEBYEP_DI=2
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02.2 Granular materials: Even though we were very convinced of the e potential of a multi-material building process we came to the conclusion that paper would not offer us sufficient possibilities to live up to the studios brief as the potential technics of treatment were too deterministic to allow for a certain emergence of the final outcome; this applied even more for industrial paper sheets. For this reason we investigated on other material combinations which would allow us to maintain the multi-material concept, but which at the same time would offer us a naturally emerging design principle to drive the further development of the studio. Following the premise that we would use biodegradable materials we began to experiment with granular materials combined in a way that opposed material properties would have a beneficent effect in the process; i.e. we tried to combine cement and sand or cement and saw dust without mixing the material, but rather using one material as a temporary support, a moulding platform for the deposition of the second material. In The hydration process the cement is then hardened while the sand as well as the fibres of saw dust and the grains of sand only stick to each other as serve as a support as long as they are wet. As soon as they begin to dry they hydrate the cement for a second time and continue to improve its strength and finally begin to fall apart. That means that the support can be removed and eventually be reused.
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From here we went on using these materials in a dry state; instead of filling the whole layer surface at once we started pouring material piles inspired by an AA DRL research project with the title of “hosmenos� who already had researched in this field.
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03 New Ways of Building
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03 New ways of building In architecture the 70’s have been a decade of intense experimentation with new ways of using material and the intention to derived new typologies from this research. Two case studies in particular have inspired us while developing our project: 03.1 Styrofoam Dome: Dow Chemical’s “self generating” styrofoam dome is the product of another radical approach to building methods. The foundation to the building can be a twelve-inch-high circular retaining wall. To this wall a four-inch wide strip of styrofoam is attached, which raises as it goes around the wall from zero to four inches in height, forming the base for the spiral dome. On the ground in the centre, motorized equipment operates a spinning boom with an operator and a heat welding machine. The boom moves around, somewhat like a compass drawing a circle, and rises with a spiralling motion at about three feet a minute. Gradually it moves in towards the centre. A man sitting in the saddle feeds an “endless” four-by-four inch strip of styrofoam into the welding machine, which heat-welds it to the previously hand-laid styrofoam. As the feeding mechanism follows its circular, rising and ever-diminishing diameter path, this spiral process creates the dome. Finally, a hole thirty-six inch diameter is left on the top, through which man, mast and movement arm can be removed. The hole is then closed with a clear plastic pop-bubble or a vent. The doors and windows are then cut and the structure is sprayed in- and outside with latex-modified concrete.
Design for the real world by Victor Papanek 1971
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The dome is ultralight weight, is secure to withstand wind speeds and great snow loads, is vermin-proof, and inexpensive. Several ones of these fifty-four-foot-diameter domes can be easily joined together into a cluster.[3]
03.2 Tao Earth House 1971 Tao Design Group This house is an experiment in adapting biologically to the environment, using new standards of space, freedom and excitement. The framework of steel and chicken-wire was erected and then sprayed with liquid polyurethane, which was moulded into shape on hardening. External surfaces were finished off with a coat of concrete for weatherproofing. Walls are thought of as membranes rather than solid masses, so instead of punching openings into them, windows are formed from translucent polyurethane. This sculptured habitat is intended for humans, and yet is easily compared to a living, growing organism. The materials are at the cutting edge of technology. In contrast the processes of design and construction are being invented through the act of building. Tools are being invented on site in response to demand. The process of building is at its essence primitive relating more closely to the way insect animals build than to modern building technology. There are no design documents on the site. All design is spontaneous, in reaction to what exists in the nature of the site, what is already built, and what the designers are visualizing. [4]
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04 Rapid prototyping
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Image courtesy of Martin Firera
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04 Rapid prototyping We realized that with this new approach of dry material deposition we had entered the field of rapid prototyping technics, establishing a combination of low tech materials and high tech computational methods for material deposition. At this point we looked out for existing additive building processes and research fields which were related to these concepts and which would offer us a basis to continue our research into a direction with a clear emergence out of an additive manufacturing method. 3-D printing is the leading additive process in digital manufacturing at the moment. Generally this technic is applied at model scale though it would mean a revolution for the building industry if taken to a real building scale. The Italian company D-Shape is currently among the first to make use of an Ink-jet process on a building scale. Starting with Sand as the basic material they apply a special formula of a binder which is able to solidify sand within a few hours and make it durable. While the project as such is a work in progress the company has started to print prototypes of simple housing units and sculptures with success. For a better understanding the following pages are supposed to give an overview of the most important additive processes in the industry.
Mono-material use at D Shape; excessive material can be removed with a brush as well
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04.1 Selective laser sintering (SLS) A high power laser (for example, a carbon dioxide laser) fuses small particles of plastic, metal (direct metal laser sintering), ceramic, or glass powders into a mass that has a desired 3-dimensional shape. The laser selectively fuses powdered material by scanning cross-sections generated from a 3-D digital description of the part (for example from a CAD file or scan data) on the surface of a powder bed. After each cross-section is scanned, the powder bed is lowered by one layer thickness, a new layer of material is applied on top, and the process is repeated until the part is completed. The SLS machine preheats the bulk powder material in the powder bed somewhat below its melting point, to make it easier for the pulsed laser to raise the temperature of the selected regions the rest of the way to the melting point.
include polymers such as nylon, (neat, glass-filled or with other fillers) or polystyrene, metals including steel, titanium, alloy mixtures, and composites and green sand. The physical process can be full melting, partial melting, or liquid-phase sintering.
Depending on the material, up to 100% density can be achieved with material properties comparable to those from conventional manufacturing methods. In many cases large numbers of parts can be packed within the powder bed, allowing very high productivity. [1]
Some SLS machines use single-component powder, such as direct metal laser sintering. However, most SLS machines use two-component powders, typically either coated powder or a powder mixture. In single-component powders, the laser melts only the outer surface of the particles (surface melting), fusing the solid non-melted cores to each other and to the previous layer. SLS can produce parts from a relatively wide range of commercially available powder materials. These
http://en.wikipedia.org/wiki/File:Selective_laser_melting_system_ schematic.jpg
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04.2 Fused Deposition Modelling (FDM) FDM works on an "additive" principle by laying down material in layers. A plastic filament or metal wire is unwound from a coil and supplies material to an extrusion nozzle which can turn the flow on and off. The nozzle is heated to melt the material and can be moved in both horizontal and vertical directions by a numerically controlled mechanism, directly controlled by a computer-aided manufacturing (CAM) software package. The model or part is produced by extruding small beads of thermoplastic material to form layers as the material hardens immediately after extrusion from the nozzle. Stepper motors or servo motors are typically employed to move the extrusion head. Several materials are available with different tradeoffs between strength and temperature properties. As well as acrylonitrile butadiene styrene (ABS) polymer, polycarbonates, polycaprolactone, polyphenylsulfones and waxes. A "water-soluble" material can be used for making temporary supports while manufacturing is in progress, this soluble support material is quickly dissolved with specialized mechanical agitation equipment utilizing a precisely heated sodium hydroxide solution. The term “ Fused Deposition Modelling “and its abbreviation to FDM are trademarked by Stratasys Inc. The exactly equivalent term, fused filament fabrication (FFF), was coined by the members of the RepRap project to give a phrase that would be legally unconstrained in its use. [2]
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Water soluble support material
04.3 Stereolitography (SLA) Stereolithography is an additive manufacturing process using a vat of liquid UV-curable photo polymer “resin� and a UV laser to build parts a layer at a time. On each layer, the laser beam traces a part cross-section pattern on the surface of the liquid resin. Exposure to the UV laser light cures, solidifies the pattern traced on the resin and adheres it to the layer below. After a pattern has been traced, the SLA’s elevator platform descends by a single layer thickness. Then, a resin-filled blade sweeps across the part cross section, re-coating it with fresh material. On this new liquid surface, the subsequent layer pattern is traced, adhering to the previous layer. After building, parts are cleaned of excess resin by immersion in a chemical bath and then cured in a UV oven. Stereolithography requires the use of support structures to attach the part to the elevator platform and to prevent certain geometry from not only deflecting due to gravity, but to also accurately hold the 2-D cross sections in place such that they resist lateral pressure from the recoater blade. Supports are generated automatically during the preparation of 3-D CAD models for use on the stereolithography machine, although they may be manipulated manually. Supports must be removed from the finished product manually. 3d printing The printer creates the model one layer at a time by spreading a layer of powder (plaster, or resins) and ink-jet printing a binder in the cross-section of the part. The process is repeated until every layer is printed. This technology is the only one that allows for the printing of full colour prototypes. This method also allows overhangs. It is also recognized as the fastest method. Mono-material use in a c corp 3d printer ; excessive material can be removed with a brush
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05 Intelligent material networks
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Image of hip bone structure http://upload.wikimedia.org/wikipedia/commons/8/8a/Human_hip_bone_texture.jpg
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05 Intelligent material networks 05.1 Physical performance Nowadays’s low energy standards give precise guidelines for the technics regarding insulation, heat gain, air exchange, regenerative heat recovery and how these regulative instruments can help to reduce the energetic footprint of a building. The main idea is simple; the lowest amount of energy is to be used or wasted while making sure that pleasant living conditions are maintained inside a building. Analysing the physical properties of our main materials such as cement, sand, saw dust and even soil we realize that all these materials have a thermal conductivity which is about 10 to 100 times higher than air combine with a heat capacity which is close to double the value of air. In an arid desert climate this means for example that these materials unless they are very porous can work as a heat storage and will exchange heat with a certain delay over time. This can be an advantage if heat gains during the day can be used to level cool temperature in the night time. The degree of porosity or perforation in the material system is relevant for the regulation of air circulation and can be used to regulate the heat capacity of the envisioned living unit. Referring back to the programmable material network and its internal built up this means that it is possible to design the physical performance of the complete material system by locally influencing its materiality, the material location and if or if not a support material such as saw dust is going to be removed after the structure has dried out or if it will remain in the system.
Cavity from removed support material ( saw dust ) can work as duct for air ventilation
Structural cement
Over all porosity of network can influence light transmission and heat capacity
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Remaining support material reduces heat connectivity ( Insulation )
The number of environmental factors which could be linked into the computational control of deposition are countless; never the less the below chart is supposed to give an overview of the functions and interactions which can be dealt with in the network serving as an inhabitable skin. The main factors in this process are lighting, heat gain or protection against heat, air flow and sound.
exterior
skin
interior
external air temperature
solar radiation
openings
lighting
sun glazing redirection protection for sun of light protection
glare
visual connection
air quality
glare insolation heat protection mass for protection glass heat savings
room inner surface temperature temperature
temperature of brought in air
ventilation through openings
air exchange
air quality
sound source
sound protection
sound
sound insulation
wind
wind protection
wind speed
Modified version of facade interface scheme of Gerhard Hausladen’s “ClimaDesign� page 40
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05.2 Following nature’s example It is our intention that structure and architectural space will emerge out of the connection and reaction of the building machine to the existing environment. There are several examples in nature which show how such an approach can be built up following a recurrent but quite limited rule set; Rupert Soar’s “Beyond biomimicry” documents in detail how the various duct sizes in the termite mound make up a refined system of mixed forced and natural air flow which allows for a very efficient control of gas and humidity exchange in the mound. The rule set behind the machinic building process can be inspired by this example;
Functional organization of a termite mound. - Beyond biomimicry , Rupert Soar
Functional organization of the lung- Beyond biomimicry , Rupert Soar
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Two early models for mound ventilation. Left. Thermosiphon flow thought to occur in capped chimney mounds. Right. Induced flow thought to occur in open chimney mounds - Beyond biomimicry , Rupert Soar
Model for swarm regulation of the nest environment- Beyond biomimicry , Rupert Soar
Hypothetical pendelluft ventilation in the termite mound and nest. - Beyond biomimicry , Rupert Soar
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06 Material treatment
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06 Material treatment 06.1 Relation between layer thickness and penetration depth in hardening process: If water is sprayed on a pile of dry, fine granular material such as cement the wettened material part begin to crack in several areas. In order to avoid this the relation between layer thickness and amount of sprayed water has to be equilibrated. This equilibrium is maintained as long as the amount of sprayed water is sufficient to wetten all grains of material without leaving dry parts in-between wettened clusters. The first pile clearly shows the cracks which derive from insufficient watering while piles two to four show a fairly homogeneous surface quality which also results in a better hardening process.
Excessive pile thickness Material not sufficiently wettened
Cracks
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Relation of pile size and process of solidification through spraying of water Remaining not solidified material (tested with plaster and cement ) Solidified material (tested with plaster and cement )
Thin layer deposition Pile wettened in thin layers with manual spraying device spraying twice
Thin layer deposition with cement and sand Pile wettened in thin layers with manual spraying device spraying twice
Thin layer deposition with cement Pile wettened in thin layers with manual spraying device spraying four times
Material homogeneously wettened - no cracks
Material homogeneously wettened - no cracks
Material homogeneously wettened - no cracks
06.2 Sequence of Deposition and Layering: In our test we found out that the deposition order makes a big difference in the internal layering between the piles of material. If piles are deposited one after the other in a sequence of pixels this means that one piles is partially created on top of the other and covers it as it happens always when one material is poured on top of another. If instead material is deposited from multiple nozzles at the same time a vertical partition between piles is generated. This notion can be used in order to generate a transition between rhomboid and vertical structures in the inner organization of the printing process with a multi-material. Out of this we get three directions for the development of a prototype to test the deposition process.
Overlapping partition
Vertical partition 41
Option A: We want to make sure that we will be able to print overlaps and vertical partitions for every pixel of a printable area. This means that need as many nozzles for deposition as we have pixels. The mock-up would consequentially result in a very numerous array of nozzles. Option B :
A: contemporary deposition of material with vertical divisions extruded in a line
B: consecutive deposition of material with overlapping piles place as pixels
We are aware that we want to keep the mechanism simple with more ease of control; that is why we are going to use a limited array of nozzles in a linear setup.
Printing vertical partitions within a large number of piles is also a matter of resolution; in consequence if the number of piles is high enough what seems to be a zig zag line in between the contours of a few piles becomes almost a straight separation if we consider many piles above each other in a large system.
osition vement during dep
Option C:
A:
Extrusion through mo
That means that we will be able to print vertical and overlapping partitions within one row and we would be able to extrude the row by combining the deposition process with a lateral movement of the nozzles.
B:
Possibilities of deposition in one single layer
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Linear array of 3 nozzles - By moving the array in its position order A can be reproduced without restriction on whatever surface
B
B
A
B
B
B
A
B
A
B
B
A
A
B
B
A
A
A
B
A
A
B
A
B
A
B
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MATERIAL CATEGORY
Piling + Spraying
PROCESS CATEGORY
SAMPLE NAME
Mechanical + Chemical
Rough
CODE
[MW]
Description_ this material sample is based upon the investigation of a multimaterial granular deposition process with the aim of generating material networks with inner voids out of sand, cement and saw dust.
Material sample created by hand from cement, sand and saw dust
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06.3 Material network and material removal: Even though many examples of multi-material tests with granular material can be found on the “hosmenosâ€? project we decided to do our own test; this was particularly necessary as we needed to investigate on the possibilities of removing our support material, which in the case of our tests was saw dust. In this sample of 30 x 30 x 10 cmÂł the saw dust took at least 3 days to dry out. After this time frame the material began partially to fall off on its own in very exposed areas; in other areas which were more enclosed in the material body instead we tried to remove the saw dust by burning it , by removing it manually and by vacuuming it. Because of the high material density of the saw dust in the body and remaining humidity it did not burn, but only slightly glimmed. So constant air circulation would be need for that process which apart from that would increase the total CO2 impact of the final result. Manual removal proved more efficient though it was of course work intensive. That is why we have come to the conclusion that the best method for material removal in this case would be a mixture of natural drying and local vacuuming where cavities are desired.
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06.4 Manually controlled deposition of a complete material network: With the intention of gradually increasing the amount of combined materials in the system and along with this also reaching more and more control over the piles deposition we decided to do some more tests by hand laying particular focus on an alternative support material which would be easier to dissolve if required. The below material sample of 30x30 cm² was done using a combination of structural mortar and saw dust, salt and semolina; the materials have been poured in dry state following a predefined order on an engraved MDF board. The hardening process has been initiated through continuous spraying of water.
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Pattern for manual deposition
1
2
3
The second handmade sample was done with mortar, saw dust, soil and finally seeds of grass. The return to a material which would be able to give start to plant life was important to us as it had been part of our concept from the beginning of the project phase. Soil fertilized through seeds can be used as a permanent support material; once plants start to grow inside and on the material system, that is the wall of the later building they can positively influence the humidity and air quality inside the dwelling.
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06.5 Material interactions:
Material overview
While testing various materials and material combinations in the manual production of material samples we developed a certain intuition and knowledge of which materials best work together in our process and which combinations are less indicated for a good result. The material table on the right illustrates and documents our experience gained from these tests and may serve as a quick introduction of the main criteria we are considering and intend to control in the over all process.
Sand as a support material is able to increase in stability while storing water;
Sand
Sawdust
Saw dust has less structural stability than sand in its wet state which results in a higher compression when loads are applied. It can as well be efficiently used for insulation tasks.
Compost
Soil with its uncountable minerals is able to host seeds and bring them to new life if the environmental conditions are appropriate; it can be used as a support or a supported material.
Support
Salt considerably weekens cement structures. Salt
As plaster contains sodium by default in combination with salty water its structural strength can be increased. Cement is a derivative of limestone; therefore these two materials work well together. Also combinations with plaster are possible.
Limestone Powder
Structural
Cement
Water
Plaster
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In addition to water storage, evaporating water can be used to enhance another material’s hydration processes.
Natural formation of softly rounded piles at 35° from horizontal axis.
Similar to sand saw dust allows for good water storage when used as support. Just as with sand evaporating water can be useful for hydration of granular materials.
Formation of low density softly rounded piles with high inner friction between single grains of material
Water is the life bringing element in combination with soil. In large quantities it leads to erosion; if used only for general wettening it increases the soils strength under compression.
With a very heterogeneous inner builtup soil is comparably difficult to deposit in equal amounts. Consequently pile may show a less homogeneous surface pattern.
Salt dissolves very well in water, that means it can easily be removed.
Piles of salt form naturally with a distinct granular surface.
Scaffolding for permanent use
Recommend for temporary internal use
Recommend for external use
Temporary protection against water is possible by applying a layer of absorbing granular material on top. Limestone can be eroded through streams of water; this would allow for smoothening of sharp edges over time. Acid would generally dissolve part of the mentioned granular materials; precise control over which material should stay or be dissolved is not possible though.
Similar to cement grains of limestone have a very high friction among each other which results in a steeper angle in the pile formation compared to the 35° degrees typical for sand.
Known methods of providing scaffolding can be substituted by using the linked material
Formation of piles
Clay Powder
Acid
Seeds
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Cement behaviour
Dry Pile
High friction between material grains cause a steeper pile formation.
Deposit & Watering
Hydration of the material grains while they are falling further increases the steepness of the pile.
Portland Valderrivas
Dry Pile
Cement
Grey thin set Cement Deposit & Watering
Dry Pile
Siliceous Mortar Deposit & Watering
Nozzle
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Piles shape
The pile shape is predictable and easy to control; pile shape is more rounded compared to Portland cement.
Watering after
Watering after
As the grains of material stay in very close contact water sprayed after deposition tends to penetrate the pile partially and increases its over all roughness.
Sprayed water penetrates the pile quite well, nevertheless cracks appear on the pile surface.
Machine The best pile quality that fit in the best way to our machinic system
Pile shape is easy to be predict; While spraying some material is washed out.
Shape of piles is close to sand piles; due to different mass sand and cement grains get separated while falling.
Watering after
Water can penetrate the pile well, due to the mixture of large and small grains; pile shape is widely maintained.
Cone shape tends to get flatter; though different grain sizes are detached less while falling.
Water
Quality
Regular building process
Regular isolation wall
Form work
Evaluation of environment
Wall
Substructure
Isolation
Stucco
Generation of material and deposition logics
Climate conditions
Multi-material process Multi material model of insulation
Multi material deposition
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07 Simulation
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07 Simulation 07.1 Solvent (Particle interactivity):
07.2 SandBox-2D (Material network I):
The aim of this simulation was to investigate complex particle behaviour and interaction. Particles of different materials were roughly simulated using the principles of cellular automaton and a basic set of interaction rules were set for every material and programmed into the simulation. The main goal of this work was to show how the relationships between different materials (some of them with phase changing properties) can build up complex material networks and produce results that are unexpected or hard to predict without computer simulation. Particles of a solid not dissoluble material were simulated in order to provide a scaffolding material. Water was simulated as solvent and salt was used
as phase changing material which can be dissolved by water and in that way eventually be removed from the material network. Also sand was simulated, with its piling behaviour, as the main component of the network. Although a quite realistic environment was created and the principles of the future simulations were set, this first test environment was more a declaration of intentions than a useful testing environment for the material networks that we wanted to generate.
As we began to realize that sand and sandy materials would become the basic ingredients of our work, a two dimensional sand simulation system was programmed where the deposition of the sand particles could be controlled. Sand deposition nozzles were brought into the system where their position could be defined and the amount of poured sand could be controlled. This gave us the ability to generate 2D-sections of the sand-like material networks that showed their physical structure. This gave us the first feedback to select what material tests to start with. This, together with the interaction principles that where set up in the first simulation, would be the base for the future 3D-simulation.
Solvent simulation of particle ineraction
SandBox-2D - simulation of permanent scaffolding
SandBox-2D - simulation of inner material patterns
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07.3 Sand machine (Machine behaviour): In another order of things, we established a simulation environment related to the sand and cement deposition machine we were building (based upon our primogenitor light-sensor-plotter). In this setup, the reaction of the machine in front of different environmental factors was simulated, establishing a real time interaction with building site conditions like amount of light or IR radiation, directional sound levels or dominant wind directions. Here we studied the possibilities of letting the site give input parameters that determine the final shape and properties of the built structures.
Sand machine - light mapping 1
Sand machine - light mapping 2
Sand machine - light mapping 3
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07.4 SandBox-3D (Material network II) With this simulation and optimization environment we wanted to create a basic universal tool that allowed us work in three tightly related fields: 1. Testing physical results (material distribution) of different material deposition strategies and relate them to a set of operation commands specially created for our deposition nozzle mounted on a ‘transportation’ machine (a standard milling machine or our own specialized machine).
2. Relate the material distribution obtained (material network) to some key parameters that are important and would affect the systems performance and drive the design, and optimise the material distribution according to this parameters. The main strategy consisted in tracking the continuity of every different type of material that composes the network and establish ‘material lines’ that could be used for doing performance calculations and further optimization.
Conventional way for putting Pipes in walls Pipes are considered an addon the structural system
Two materials being poured in a preconceived pattern
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3. Provide a working environment for the sample printing process that visualizes the files before or at the same time as they are printed on the machine: graphic interface for the printing process.
3-D Modeling
Extraction of coordinates
Instead of pipes cavities are defined within solid material
Coordinates for deposition are extracted from the 3-D model
DNA
Material interaction
Genetic code
A< B Selection and mutation
Fittnes check
Performance calculation
Automatic geometry generation
Voxel coordinates to geometry Simulated material voxels can be exported to Grasshopper and transformed into geometry
G-code driven simulation According to g-code material deposition is simulated providing the final result of the deposition process.
G-code
Machine
Printing
Building part
G- code is generated from extracted coordinates to drive the machine movement and quantity of material
Moving according to gen- Material type, position and Final material syserated g-code quantity poured by matem or building part chinic device printed
Section mode: Geometric material interaction can be displayed and analysed in x,y and z axis
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SEQUENCE AND NOZZLE
Visualization parameters
PAUSE
SEQUENCE
XRMODE
CHOOSE A CMD SEQUENCE
VOXELS
AUTO
MANUAL
PLAY
PAUSE
BEG
Virtual nozzle
BAK
RELOAD RECORD
RESTART
VAL
FWD
J CODE
P1
P2
M CODE
MAT
AMOUNT
CODE
END P3
Current code
ADD
Edit code
REMOVE
!!
SAVE EXPORT
7 !8 !8 ! !! 7 !8 !8 !! 7 !8!8 ! !! 7 9 !89 !8 !! 7 9 !89 !8 !
x
CLEAR
7 !8 !8 ! 7 !8 !8 !!
y
File selection Simulation mode
Export simulation to voxels
NOZZLE
Simulation container
SPEED
Simulation progress
z 538 / 595 709327
cmd millisec
25872
GLOBAL MULTIPLIER MULTI
particles
2031
active
149
MULTI
SLIDER
NAME
NAME
NAME
NAME
M1x VAL
M2x VAL
M3x VAL
M4x VAL
AMOUNT
AMOUNT
AMOUNT
AMOUNT
TOTAL
TOTAL
TOTAL
TOTAL
X
Y
Z
SHIFT
SX
SY
SZ
Nozzle parameters Deposited particles
full hits
07.5 SandBox_3D user manual:
Procedure:
This software simulates a code-driven sand-like material deposition system. It transforms commands into machine operations, mainly three dimensional jogs like the ones performed by a 3 axes milling machine and material deposition operations, similar to the ones done by 3-D printers.
To simulate a deposition process select a code sequence in the pull down list, the simulation will start automatically. You can pause it pressing â&#x20AC;&#x2DC;sâ&#x20AC;&#x2122; or â&#x20AC;&#x2DC;pauseâ&#x20AC;&#x2122;. Dragging the mouse with the left mouse button pressed you can rotate the container. Pressing the middle mouse button while dragging the mouse displaces the sand box on the graphic screen. The mouse wheel zooms in and out of the scene. You can see the code responding to the sequence being executed in the â&#x20AC;&#x2DC;codeâ&#x20AC;&#x2122; box. The lines that are currently being executed are shown in detail and can be edited. The number on the red background shows the progress of the simulation. You can activate different grid modes by pressing â&#x20AC;&#x2DC;gâ&#x20AC;&#x2122; and show and hide
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the path described by the nozzle pressing â&#x20AC;&#x2DC;tâ&#x20AC;&#x2122; (trace). The four materials that can be simulated are shown in four different colours. To speed up the simulation go into â&#x20AC;&#x2DC;blind modeâ&#x20AC;&#x2122; pressing â&#x20AC;&#x2DC;bâ&#x20AC;&#x2122;; the real time graphical representation will stop and just a limited number of progress indicators will remain active, giving you feed back on the state of the process. Pressing x, y or z you will be cutting the material network by the corresponding plane; consider it as a tomography. Press â&#x20AC;&#x2DC;râ&#x20AC;&#x2122; to isolate the cutting plane. In order to see just one of the materials that are being deposited, press the number of the material (1 to 4). Pressing â&#x20AC;&#x2DC;0â&#x20AC;&#x2122; shows them all again. You can export the single particles that have been deposited in the container by pressing â&#x20AC;&#x2DC;sâ&#x20AC;&#x2122; (useful for rendering with external tools). The visualization mode can be switched from points to voxels pressing â&#x20AC;&#x2DC;vâ&#x20AC;&#x2122;: voxels need more calculation power than points and will slow down the representation and the simulation process. Finally, you can set a multiplying factor for the amount of material being deposited in every point â&#x20AC;&#x2DC;global multiplierâ&#x20AC;&#x2122;.
07.6 Communication with the shopbot: While we were still developing our own machinic parts to which the nozzle would be attached in the end we already worked on methods of translating pile coordinates and volumes of geometry into a gcode which would be both, easy to write and understand and flexible enough to be used not only temporarily for the shopbot, but also for the final machine. The way the resulting Grasshopper definition has been set up allowed us to generate very simple pile patterns parametrically or draw them intuitively in Rhino and later on extract the given coordinates from the given position; all piles of the same material would then be summarized in one table; mixed material tables could be consequentially combined out of these. Because of the simplicity of the established g-code it could be easily manipulated by hand. Because of this we extended the previous definition to be able to read and translate g-code files into points again and work as a simple g-code visualizer.
Total amount of piles of one material [cm続] Approximate amount of material to pour in one pile [cm続]
M1 material 1
Coordinates of piles to be deposited
M2 material 2
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07.7 Granular material samples:
Various combinations of removed support material
M1, M2, M3
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Showing internal structural columns composed of two solid materials
The voxel based processing model was of course an abstraction of the physical deposition process. With the intention of having and easy to control and speed optimised simulation model working within the computational resources of a single computer we opted for a cubic representation of the single voxel to be rendered out. The outcome of this visualization allows us to do a qualitative analysis of the geometric analysis of single pile layers of the same material. The images on the left illustrate the square outcome of the simulation in different stages; three materials have been used during deposition so by hiding one or more of the e material layers connections and tunnels which would emerge in the physical deposition process can be analysed before deposition. This would give us a basis to develop a strategy of where we would best place a certain kind of solid or support material in order to generate a certain physical performance within the material system. Another idea consisted in using the voxel model for a structural performance analysis even though at that point of the project we did not dispose of the necessary technics to do so.
Real material sample
Same deposition strategy simulated with two materials
Simulation allows for analysis of removable and interior material parts
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SR J3 119,184,0 M1 100 J3 150,144,0 M1 100 J3 197,125,0 M1 100 J3 248,131,0 M1 100 J3 289,162,0 M1 100 J3 309,208,0
M1 100 J3 325,249,0 M1 100 J3 357,279,0 M1 100 J3 398,292,0 M1 100 J3 442,287,0 M1 100 J3 479,263,0 M1 100 J3 46,153,0
M2 25 J3 74,117,0 M2 25 J3 102,81,0 M2 25 J3 144,62,0 M2 25 J3 187,47,0 M2 25 J3 191,215,0 M2 25 J3 231,220,0
M2 25 J3 232,48,0 M2 25 J3 242,258,0 M2 25 J3 262,292,0 M2 25 J3 277,59,0 M2 25 J3 286,322,0 M2 25 J3 316,82,0
Extracted g-code from point cloud model containing pile coordinates and quantity
Material flow from higher to lower piles creates vertical struts.
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M2 25 J3 317,345,0 M2 25 J3 348,114,0 M2 25 J3 353,360,0 M2 25 J3 373,152,0 M2 25 J3 386,196,0 M2 25
Material deposition simulation - 3-D view and section in x,y,z axis
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07.8 Creation of material channels: Large part of our thesis is based on the idea of being able to remove temporary scaffolding materials used during the deposition to support the structural material before this has become hard. In order to remove materials from a dense material network we need ducts which connections from one part of the material volume to the other. Only like this it can be assure that material can or fall out of the network through interaction of wind or that it can actively be removed. The principal idea of the removal process foresees
Block volume and volume for support material
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that the logics of the multi-material built-up are based on an interactive model which would be able to take into consideration how channels would have to be engineered to facilitate material removal. Nevertheless at this point of the project we still had to test preconceived concepts of what the best geometric orders and the respective materials would look like. For preparation of a real material sample with channels we developed a Grashopper script which through boolean analysis would allow us to define support and structural material in a point matrix to define the coordinates and respective material to be
poured by the nozzle of our device. Later the generated coordinates for deposition have been simulated in processing.
Point matrix with channel volume for boolean operation to generate material continuity
Material deposition simulation - 3-D view and section in x,y,z axis
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08 Machinic prototypes
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Filling the bottles with coloured sand
Physical test model for pile generation
Deposition pattern in section; vertical partitions and blur visible
08 Machinic prototypes Immediately after our first material test of pouring sand piles by hand we wanted to start investing the machinic potential of the process and the formations emerging during the deposition of multiple piles of material. In order to be able to do that we built a test nozzle consisting of a simple MDF box and three standard plastic bottle containing material the openings of which could be opened and closed through servos.
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08.1 Nozzle prototype of linear array:
08.2 Hacking the shopbot milling machine:
The test set up shows step by step the filling of the bottles and the deposition of the coloured sand out of the bottle array controlled by Arduino. Several steps had to be repeated in order to fill the test box as shown on the right image. Though it is possible to see the vertical partition between continuously deposited piles, it becomes also visible that the slightest delay in deposition between piles immediately leads to a zig zag shaped blur in the material boundaries.
The next tests were to include machinic control of all involved mechanisms; for this reason we decided to connect a modified version of the nozzle prototype to Iaacâ&#x20AC;&#x2122;s 3-axis milling machine - the shopbot. Using the 3 axes of the milling machine we were able to have precise control over the position of the deposition; we started drawing various testing patterns to verify the functioning of our GH and processing scripts for the extraction of coordinates from the drawing and communication with the shop bot; these tests were supposed to show a first level of machinic control before stepping forward to experiment multilayered deposition with multiple materials.
Standard plastic bottle; bottom cut
Connection to milling machine
Nozzle opening with control blade and servo
Pile grid
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Continuous servo
Tread tube for dense material removal
Nozzle for high density materials
Servos for sand-like nozzle
M4 M1 M2
Connection to milling machine
Nozzle opening with control blade and servo
Funnel to bundle material from 4 nozzles
Funnel
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M3
09.3 Improved nozzle: In order to get one step closer towards the multimaterial deposition process we are aiming for we needed to redesign our nozzle to work with more than one material at a time. For this reason we equipped the new nozzle with four material chambers; 2 chambers ( M1, M3 ) were designed to work with sand-like material which has a low cohesion between the single grains of sand resulting from a comparably low friction. The other two chambers ( M2, M4 ) were to work with materials such as saw dust, cement or mortar which are more difficult to deposit due to the high friction between the grains of material. For this reason we introduced a wooden tube with an engraved helix profile and laterally fixed strips which would continuously move the whole material volume in the chamber and therefore transport the material towards the exit whole into the deposition funnel. With this technic we managed to gain control in depositing exact amounts of material which was the basic step before being able to built up more sophisticated material compositions.
Gradually increasing pile volume in sand and mortar;
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09 Digital control
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First partial layer
First + second partial layer
+
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First + second + third partial layer
+
09 Digital control 09.1 Material Layers: The outcome of the printing process is highly dependent on the interaction of the various layers of material; a careful calibration between the digital models and the physical deposition is required to achieve predictable and controllable outcomes. On our way of gaining control over the physical deposition we developed a layering model consisting of an entity of three pile layers deposited in a triangular grid in a way that each pile of the following layer fills as much as possible the gaps originating from the pile of the previous layer. After three iterations, the last one containing only about half the material quantity of the previous two ones, we manage like this to generate a nearly flat surface again. This approach of filling gaps was considered a way of generating a printed volume in very controlled steps until we would be able to handle more interactive configurations including also varying piles sizes.
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10.2 Digitally controlled deposition of a complete material network: With the last manual tests having proved that we are able to combine at least 4 different material to create temporary or permanent supports, voids, ducts of even growing parts within the material system we proceeded to repeat this process, this time still with only two materials applying digital control in deposition using the shopbot. A g-code was generated from the pile coordinate pattern displayed on the right hand side. The order of deposition was executed in three turns depositing first piles of same size in the position of black and grey coordinates with readily available mortar and finally pouring have sized piles in the place of white coordinates. This process has been repeated twice.
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1
2
3
1
2
3
1
2
3
Material hydration
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09.3 Material removal through air presssure ( Erosion through wind turbulence ): In order to obtain desired ducts in the material system for ventilation or eventually water drainage we were researching on options for material removal based on the characteristics of the used support material. Granular non-soluble material such as sand and saw dust could be removed in a short time frame with an air pressure gun; in a much longer time frame natural wind turbulences in specific areas of the site could perform the same task.
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10.4 Creation of ducts within the network: Through a boolean operation the below volume was converted into a grid of coordinates for deposition; the result has been simulated and printed later on.
Vertical connection
Sand
Cement
Removable support
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Horizontal connection
Sand as temporary support
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Cement as structure
Saw dust retained inside to perform as insulation
Horizontal duct after removal of saw dust through air pressure
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10 Autonomous Device
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Rotation follows direction of highest light intensity; where measured light levels are equal for both sensors the machine stops while it continues to draw; this results in areas of increased density in the drawing and allows to read out areas with equal light levels for both sensors. 84
Rotation is constant in anti-clockwise direction; light levels are continuously measured and remapped on the amplitude of the movement along the printer axis. In consequence the amplitude of the drawn line is a direct representation of the measured light level; the machine become a light detection device.
10 Autonomous device 10.1 Workshop in hacking devices ( light detector ) The workshop in digital tectonics gave the start and introduction for the studio in order to understand in an intuitive way how to hack already existing machines in order to transform them into something new; this can happen or by adding a different function to an existing mechanism or by taking working mechanical parts apart and recombine them to change the way they work. In our case we used a standard ink jet printer and a couple of stepper and DC motors to construct a radial apparatus which would move and draw according to incident light values measured by two lateral light sensors. The machine was driven by an Arduino which would evaluate the light data at every step and create a feedback loop by controlling the stepper motors for rotational movement and lateral movement of the drawing axis accordingly. We programmed two scenarios: 1) light sensor 1 & light sensor 2 are active; if light sensor 1 < light sensor 2; move towards light sensor 1; in the mean time move back at forth at constant speed on printer axis
Light sensor 1
Light sensor 2
2) light sensor 1 is active; rotate at constant speed; get values from light sensor 1 and remap to range of movement on printer axis
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10.2 First prototype:
multi-material nozzle. Conceptually we planned for combining the nozzle we already used in combination with the shopbot also with our prototype, so a simple connection between nozzle base and former printing axis would be sufficient for first machinic deposition tests responding to a radial logic.
ap
pro
x.
2,5
m
Contemporaneously with the development of the nozzle for material deposition we started developing the machinic device on which the nozzle should be mounted and from which would further influence the final design possibilities through the various degrees of movement of the machine. Inspired by our “hacking devices” exercise we decided to rebuild a bigger version of our former “light detector” and therefore base the deposition process on a rotational movement. In this process the printing axis of a custom A0 plotter has been reused to build the prototype of the machine to which we would later on attach the
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Shopbot nozzle reused on deposition machine
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10.3 Prototype update: The first version of the machinic device was still quite heavy in construction; for that reason we decided to redesign part of the main structural components of the machine in order to get one step closer to the light weight mechanism we actually imagined as our final prototype.
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By reducing excessive weight and building up a stiffer structure of mostly aluminium and few MDF parts we were expecting a better performance in the sense of general speed of movement and reaction time.
Shopbot nozzle mounted below the prototyped device
Shopbot nozzle reused on modified deposition machine
Remaining MDF parts
New aluminium frame built-up
Reused tripod
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11 The device on site
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11 The device on site
Israel
11.1 The site:
Juda Desert
Negev Desert
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From the founding times of the state Israel has always been confronted with the phenomenon of desertification as a consequence of the arid climate. Over the decades through introduction of plants people managed to strengthen the ground and increase its capability to retain water which is still very precious in this region. Apart from concrete and plaster which can be gained out of local materials building materials have often to be imported which has a major impact on the energy and CO2 footprint of the overall process. Because of its historic context the desert side around Jerusalem has a strong need for an architectural language which respects the environment and does not distract from it. We are convinced that by applying a multi-material building process with locally available materials it is possible to solve existing problems of lacking housing while propagating a new building technics inspired by ancient building typologies to create low energy dwellings. â&#x20AC;&#x153;The desert provides us with the best opportunity to begin again. This is a vital element of our renaissance in Israel. For it is in mastering nature that man learns to control himself. It is in this sense, more practical than mystic, that I define our Redemption on this land.â&#x20AC;? Ben Gurionâ&#x20AC;&#x2122;s Vision
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11.2 The device: For our prototype we were bound to a maximum work scale as well as material quantity which we could use in our tests and the absolute dimensions of the deposition device are concerned. Our prototype can be considered approximately a 1:10 model of the final building machine which we envision with a 20 m span and 10 m height.
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11.3 Site Engineering: The deposition device has only a limited stock of material; for that reason it needs continuously to be refilled; material containers are going to be placed centrally on site in-between the working areas of deposition devices; even though the machines will move during deposition it must be assured that at the starting point of machinic movement is always within reach of the refilling nozzle. When the building within a certain area has been concluded the material stock is shifted into another area to allow again for short paths during refill. The stock is supposed to contain industrial materials delivered from the city nearby such as cement, saw dust and mortar while the required sand can be extracted on site. Dry support material can be reused after construction; this is supposed to happen through smaller vacuuming robots which recollect the used dry sand and saw dust and refill the material stock with it. A continuous material cycle is established.
Machines always work within reach of material stock; position of stock is subsequently shifted after one area has been completed. 2
Second material supply with limited range
3
First material supply with limited range 1
4
Range of deposition device; refilling can happen at intersections
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1. 5. 2.
4.
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3.
1.
The first material stock has been placed on site and the deposition devices operate within refilling range; the machines must be able to intersect with the radius of the refilling nozzle at one point of their path of movement; when ever the material stock in the machines drops below a critical level the machine will move back on its path top the point of refill; while returning on its path the machine will start printing already the next layer of material to optimise the covered distance per printed area.
2.
Once an area has been printed fully a new material stock is set-up or the old one is moved to a new place. As the deposition devices depend on the vicinity to the stock, this enables them to move to the new printing site.
3.
The deposition on site can happen in swarms; for that reason additional devices can be delivered on site by truck and can unfold within a relatively short time frame right where they have to start building; in case the site should not be sufficiently accessible, the machine can move to the designated place itself making use of its adaptable site- responsive hydraulic system of movement.
4.
Material cycle: After deposition building need to be hydrated to harden the structural materials; after a reasonable time frame the used support material can be removed and be reused for the next deposition process. This task is accomplished by a small vacuuming robot which bridges the distances between the deposition area and the material general material stock on site which is continuously refilled. The vacuuming process itself is directed by human workers which use human cognitive intelligence to direct the movement of the vacuuming nozzle. As soon as the vacuuming of dried support material is completed the robot moves back to the next stock and refills it.
5.
Interaction with plants: The wall built-up of the buildings depending on the materials used in its formation allows for the growth of plants in and on the outer shell of the e inhabited spaces. The introduction of plants allows for various side effects such as purification of air which passes through the plants and the porous wall systems leaving pollutants behind and absorbing water retained in the wall system; a natural system of air conditioning is generated.
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1.
2.
11.4 Sequential built-up: The machine concept is based on global transportability; for this reason the machine is designed to be transportable on a standard truck and also be shipped in containers. The graphics above illustrate a step by step built up of the single modules of the device.
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1.
Compactly bundled machinic modules are delivered on site with a standard truck including temporary control units for supervisors of the building process.
2.
The machine is detached from the truck and is gradually extended to take its full size.
3.
The machine is ready to move on site
4.
The hydraulically extendable and rotatable columns can be adapted in height to match uneven terrain or to adjust the height for material deposition.
5
Vacuuming robot which recollects dried support material under the supervision of a human worker
3.
4.
5.
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Rotatability and shifting around and along z-axis
11.5 Possibilities of machinic movement: The deposition device has been designed to allow for a flexible approach of printing in a non-laboratory environment meaning that due to its multiple possibilities of rotation and adaption in height complex scenarios of movement are possible. 1. By making the wheels align along two different radii it is possible to shift the machine centre of rotation outside its own geometry.
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Center of rotation
2. By aligning all wheels in parallel the machine will be able to move straight forward, efficiently avoiding obstacles on the site while moving from one coordinate of deposition to the next one.
3. A central hydraulic pivoting pin can lift the machine up on one site, allowing for changing pivoting centres and thus generating undulating boundaries for deposition.
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12 Machinic movement path
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12 Machinic movement path 12.1 Genetic Algorithm According to the site we would potentially be building in we may encounter various obstacles in the form of trees, rocks, mountains or steep slopes which would not allow the machine to proceed. That means that before building anything the site needs to be analysed and a possible path of move-
Grasshopper definition for simulation in Galรกpagos
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ment has to be worked out which allows to avoid the obstacles. That is why we decided to investigate on an algorithmic way of finding the ideal path of movement for the device; In the simulation abstract lines stand for real envi-
ronment objects which need to be avoided moving between a given start and a desired end point.
Galรกpagos - generative algorithm simulation of movement path
1.
2.
Continuous rotation up to 360°around a fixed centre point
3.
Continuous rotation above 90° and lower 360° around shifting centre points
Continuous rotation below or equal 90° around shifting centre points
Point structure with two movable rotation points:
4.
5.
6. angle < 180° generates curved oriented printing outlines
angle > 180° leads to entrapped curves
change of global bending direction not possible
changing center of rotation needs angle = 180° for mechanical reasons
Rotation with inverted position of centre points; first rotation limited to 180°, second rotation above 180° which leads to a blocking of the machine rotation
continuous angle = 180° generates curved printing outlines in one direction
changing center of rotation needs angle = 180° for mechanical reasons
Rotation with inverted position of centre points; first and second rotation limited to 180°, generation of straight paths
changing center of rotation needs angle = 180° for mechanical reasons
Rotation with inverted position of centre points; first and second rotation limited to 180°, second rotation below 180°; spiral movement
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Abstract site boundary
Outline of possible machine movement
12
End point to be reached in simulation
14 13
10
01. 02.
11 09
03. 04.
08 07 06
Collision with obstacle 05
04
05. 06. 07. 08. 09. 10.
03 02
11. 12.
01 13. 14.
Start point of algorithmic simulation
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12.2 Machinic movement Contemporaneously with the development of the nozzle for material deposition we started developing the machinic device on which the nozzle should be mounted and from which would further influence the final design possibilities through the various degrees of movement of the machine. By allowing for a repetitive rotational movement around inverted centres of rotation we generate a snake-like path of movement for the deposition of material.
Outline of possible machine movement
Area for wheel rotation
Outline of deposition area
Multi-material wall deposited by consecutive replacement of machine layer by layer
Start point of deposition
Obstacle; i.e. a group of trees
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Potential slope or other imitating formation
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13 Conclusion and comments Conclusion: During the development of the project we have managed to reach to a point of preconceived reproduction of shapes and spatial concepts with in a multimaterial process with the tools we have designed for that purpose. Even though the idea of a continuously evolving built-up of the material system based on environmental input and knowledge of material interaction and physical performance has always been part of our considerations and various phases of development of the project, due to the short time frame of 6 month we could not reach that far. At the point of presentation of the project we are clearly imagining the potential of a multi-material process with a feedback loop during building. The combined use of structural material and materials for temporary or permanent scaffolding can only reach its full potential if the inner built-up of the printed system is driven by some sort of self-organizing logic. If research in this field should be continued as we have done, this aspect of interactivity in combination which the building order of multiple materials would be the most interesting aspects to be persued further. Also the idea of material removal which is vital for our process has unfortunately not been investigated on sufficiently. We have come to the conclusion that support material should not be removed through water even though this process may seem very simple. As we have chosen a desert environment as our potential site, water is a very precious good and should not be wasted if possible. For this reason we have considered erosion through air turbulence over a longer time frame as the most sustainable and consistent solution of material removal. Considering this, more analysis of removability of material through wind would be required. Thinking of research in printing as a construction method it is clearly visible that 3D printing will be one of the
techniques which is considerably going to change the way we build today. The multi-material aspect of it allows to think in therms of completely replacing the current add-on system in architecture and thinking of printing complete buildings with specific material systems according to the required function. That would involve a huge change in the way of thinking building components as meaning that the usual modular thinking can evolve into a more continuous and amorph way of perceiving building parts.
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14 The team Team from left to right: Julian Hildebrand, Ohad Meyuhas, Jordi Portell, Martin Firera
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15 Literature and links Links: [1] http://en.wikipedia.org/wiki/Selective_laser_sintering [2] http://en.wikipedia.org/wiki/Fused_deposition_modeling [3] http://www.ecoredux.com/archive_project16_02.html [4] http://www.ecoredux.com/archive_project95_02.html
Literature: Beyond biomimicry - Rupert Soar http://www.esf.edu/efb/turner/publication%20pdfs/Beyond%20Biomimicry%20 MS%20distribution.pdf ClimaDesign , Lösungen für Gebäude, die mit weniger Technik mehr können Callwey - Gerhard Hausladen
Photos: Group photo by Harshad Sutar, our collegue and friend at Iaac
Latest updates on the project: Iaac-blog: www.iaacblog.com/digitaltectonics/?p=767&preview=true Project domain: www.mat-works.net
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