AREANA 3d printing sand IAAC 2011

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Index

01 Concept

02 Material

Brief Project Thesis References Introduction Material Behaviour Simulation of materials Manual experimentation Sandboxes

03 Machine

04 Geometrical catalogue

05 Configuration techniques

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Introduction Prototypes Control Composition Movement Potential

Introduction Small Medium Large Layering Vacuuming Arching Shaping Micropiling

06 Application 07 Models and Sketches

Adaptation Case Study

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01 Concept

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1.I Brief

Over billions of years of evolution, nature has been perfecting the complex methods of optimisation; processes that humans have only recently begun to grasp, explore and utilize. The realization that everything in our surroundings (artificial and natural), is the output of systemic computations is tempting us to question the inherent logic with which all these diverse systems manage to collaborate in absolut balance. While technical evolution has always been chronological, constantly building on the past through improvement, aesthetic evolution has been timeless and independent.Through adopting a scientific approach towards the logic of nature, the wisdom of ages of optimization be harvested and maniputated in new ways.

Digital Tectonics is the fusion of nature’s material properties and the unlimited possibilities created by digital design technologies. It is underlined by a shift from a product oriented design approach towads a more organic and dynamic design process. Digital technologies instead of merely being used to design an end product, turn into a platform for exploring the design process through fabrication.

Parallel advances in design computation make it possible to integrate this knowledge into the architectural field. Digital tools may be used to complete the already known analogue tools which have allowed architects such as Frei Otto and Gaudi comprehend the structural principles observed in nature. Architects are now able to stretch their creativity over diverse disciplines, harvesting their input, and orchestrating a design which results from a generative process rather than a mere visual image.

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This dissociation of architecture with product, allows for an evolved collaboration and combination of expertise areas, uniting them in the creational process. Advanced technical control and new, evolving machines need to bridge the gap between the generated designs and the real world by incorporating factors of time and motion. An architect, in charge of the process rather than the product, designs through rules and patterns and thus needs an intelligent machine. Taking advantage of the existing technologies and fabrication processes machines can be built, which can adapt themselves to the task and environment at hand.

Iaac Digital Tectonics Research studio 2010-2011 FABOTS 2.0 Faculty: Marta Male-Alemany Victor ViĂąa Brian Peters

This new design approach, combined with an intelligent production process contributes to the very urgent and global aim of sustainability. Although much of society is making an increased effort to reduce it’s Co2 footprint, the modern lifestyle inevitably keeps increasing the wear and tear of this planet, calling for architecture which is in tune with the planet rather than one that imposes itself upon it. In addition to the design strategy and fabrication method being sustainable, choosing a feasible material contributes to the planets well being by reducing the social balance. Using smart materials in an innovative, creational approach corresponds to demands such as feasibility, sustainability and applicability. But smart materials need not be innovative in themselves; smartness lies in the ingenuity of the process, which creates structures from them. Catering to the masses can be best done by applying an innovative process to simple, traditional materials, rather than applying expensive, new materials. In this way architecture helps level the economical imbalance of the planet, accepting that the feasibility of a project is a meter of its viability.

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“The task of architecture remains the same,architecture is a medium par excellence for the projection of the image of man onto the image of the world.�

Karl Chu

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1.II Project Thesis Sustainable architecture is achieved by adapting the design, material and process to the environment it caters too. AREANA set out to achieve this by approaching a traditional material in an innovative manner. Sand has some important properties. It is abundant, cheap, natural and easily accesible. Due to these properties, humans have used sand for centuries to build structures. In digital tectonics, the traditional materials are combined with innovative and experimental approaches.

AREANA is a manifestation of this research.

It can be described as “ a rigorous material exploration leading to fabrication of structures and processes, that are always in tune with the qualities of sand”.

AREANA explored the concept of an integral on-site construction and form finding process. Mimicking the way nature sculpts its surroundings through time, the existing topography found on the construction sites is transformed. Set in a sandy, dessert like environment, an autonomous “vacuum machine” collects and then directly deposits the sand, rearranging the environment into a configuration of piles and holes. This simple process ensures that the primary construction material can be sourced locally, therefore eliminating unsustainable transportation. The otherwise un-cohesive sand grains are held in place by pouring strands of a binder on the rearranged sand surface. The sand and binder mixture form a structure upon drying, using the underlying sand as a mould. AREANAs geometries are based on the singularity of the material and the systems created from the self organization of its constituent sand grains.

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Students Chryssa Karakana Carolina Miro Miguel Guerrero Pi単ar Anastasia Pistofidou By letting the material define the parameters of the project, a highly controlled, yet very simple process was devised, in which a limited set of rules enabled the exploration of the generation of large structures. Leaning on the use of algorithms to digitally generate designs, one must be aware that any digital tool is only as good as its creator. Therefore the investigation of forms and geometries was cyclic, having manual experiments constantly feeding into the digital simulations.

The key lies in the skillful and natural combination of material behaviour, machine logic, digital ease and awareness of the environment. Through this philosophy problems such as scalability of the laboratory project when applied to reality were overcome. We believe that the tool we have devised is both open and accessible to everybody and adaptable to a vast set of needs.

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1.III References AREANA is a reaction to inspiring work, both by contemporary as also traditional architects. However, rather than continuing their research, or attempting to defy it, AREANA has absorbed different concepts or insights stemming directly or indirectly from these architects and projects. In particular, attention was paid to advances made in from finding processes in the 70’s and projects similar to AREANA currently being done in architectural schools.

Figure 1_ Frei Otto_Self-forming processes The central aim of this research is the study of the emergent behaviour of these “selfforming processes’’ as he defines the pattern formation resulting from the material inherent properties and it’s internal self-organisation produced as a reaction to environmental pressures.

Figure2._ Frederick Kiesler _The Endless House In 1952, along with Buckminster Fuller’s geodesic dome, Kiesler introduces his Endless house. The concept of a series of spaces that emerge seamlessly with the same continuous surface tension, with all the surfaces working together. New technologies have emerged that are now provok- ing different questions regarding the tectonics and material potentials within the concept of The Endless House.Theory.” Kiesler believes that the essence of reality is not in the “thing” itself, but in the way it correlates and orders itself to its environment.

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Figure 3_ Magnus Larson Solidifying sand The AA project of solidifying sand was both inspiring in the way of combining material systems, fabrication techniques and computation, but mostly is was a reference about the concept of accessible architecture oriented to places with no infrastructure.

Figure 4_ Omenos AA project 2011 The laboratory work method of Osmenos project gave insight in a procedural level. Controlling and hacking existing technologies, in this case, the shopbot , allowed us to have a real time communication between the digital model and its analogue counterpart.

Figure 5_ David Sellers 1972 _Snow moulding In his snow moulding project, he makes variable moulding forms by shaping and covering snow. The surfaces of snowballs were fixed by spraying polyurethane on them. The concept of reusable free moulds makes the total construction very cheap.

Figure 6._ Anton Garcia-Abril_Trufa House An inspirational fabrication technique used to create a unique building. A temporary envelope of soil is made into which bundles of straw are placed, then the soil envelope is filled with concrete. After the hardening of the concrete, the straw is extracted by letting a cow eat it.

Figure 7._ Kappadokia This region in central Anatolia, Turkey, is home to settlements of rock houses which are set in an unusual natural environment of volcanic peaks. It is a unique example of an old technique used to build structures that are integrated into their environments.

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1.IV Sandbox Frei Otto is a point of reference concerning the efficient use of material. His experiments and consequent designs have dominated the advances made in lightweight tensile and membrane structures. Of particular interest to AREANA were the sandbox experiments, performed in his Institute for Light Weight Structures with the purpose of understanding occupancy patterns in nature. The experiments used sand flow apparatus in order to study the expansion of growing territories. Two wooden boxes, open at the top, are mounted one on top of the other. The upper box has apertures of varying diameter in its floor, which can be opened and closed. After filling the upper box with sand, the apertures are opened, allowing the sand to flow down into the lower box. As the sand flows, it leaves craters in the sand surface of the top box, while it forms piles in the lower box.

By varying the diameters of the holes, the speed of the falling sand is influenced. In this way, small adjustments can lead to completely different results. Interesting, is to observe the dominance of some formations over the others although their expansions were started at the same time.

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Frei Otto Munchen Stadium 1972

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02 Material Central to AREANA was to gain an understanding of the self-organizing nature of granular materials and the self-optimizing flow patterns of viscous materials, through experimentation. With the performance of these materials leading the design process, complex geometries were seen to emerge from the very basic synergy of the natures of the two materials. Performance orientated design was sought after by having the material dictate the shape rather than the shape being imposed on the material. To this end, the research was dually aimed at unearthing the materiality of the structures constituents on one hand, and on the other hand, at devising a suitable production process in which the defined patterns and rules were brought back to their essence so that they may combine with the extrinsic parameters of the environment and thus function in a highly adaptable manner.

Sand was chosen to represent the granular material in the laboratory experiments. It is a simple material, abundantly found on earth and innate to the building of structures. As the machine is to build in situ, a naturally sandy environment would provide the main construction component. By neither adding nor removing material, the resulting structure would emerge from its direct environment.

Despite the beneficial building characteristics sand posses, it´s lack of cohesiveness means that it bares little structural value on its own.

With the addition of a suitable binder, the sand grains can be held in place and thereby form a structure. Regular glue was used to represent this viscous binder in the laboratory experiments.

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2.I Material Behaviour_ Sand

A self organized granular material

Sand is a granular material with a grain size ranging from 0.0625 mm to 2mm. Being composed of finely divided rock and mineral particles, the composition of sand varies according to its origin with silica being its most common constituent in desert areas. As a building material, sand has many beneficial characteristics and has therefore been used extensively for this purpose in the past. The grains are very resistant to compressive forces and small enough to be included into building elements of various shapes. By carrying out numerous experiments in which controlled variations were applied, the behavioural parameters of this material were unearthed.

The experiments were centred on the formation of a single sand pile, shaped by the self-organization of the sand grains under gravity. Liquefaction is a property of granular substances, which makes reference to the liquid like behaviour manifested by a collection of solid grains.

depositing

Sands potential to create forms and patterns, springs from this property. These patterns, emerging from the interaction of the individual grains according to the self-organizational laws of the particular material, always adhere to the boundaries of these laws, staying within the limits defined by the critical state.

Sand grains pile up and distribute themselves according to cellular automata rules, arranging themselves into tight packed cone-shaped piles with an angle of 35 %. This critical state, achieved by self-organization, is scale-less and independent of the individual grains. It is a relational pattern, which at a macro level manifests itself as a constant behavior irrespective of the variations of its constituents.

Sand dunes, for example, are constantly shifting; their sand grains continuously reorganizing themselves if altered by external factors such as wind forces. The sand grains are in constant movement, while the sand dunes conserve their characteristic, almost solid looking form, which is shaped by sands critical state. vacumming b

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Sand is a naturally occuring granular material composed of finely divided rock and mineral particles. Its natural flow forms piles of 35째 in ideal conditions.

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2.II Material Behaviour_ Binder The liquidity the glue possesses allows it to be poured on top of the sand pile surfaces at certain deposition points and trickle down under the force of gravity. On the other hand the viscosity of the glue limits the penetration thickness of the glue into the sand pile, therefore resulting in a shell- like structure rather than a solid. As the perfect addition to the binding properties of the glue, it hardens with time upon contact with air. In this way, the pouring of the glue is the one and only process needed during construction, being able to be done in any, dry, environment.

While the self-organization of the glue occurs at a molecular level, the overall morphology and resulting sand glue structure emerge from a synergetic relationship between the micro and macro levels. Viscosity is the glue’s most important property and variable. This internal resistance to flow is determined by the glues resistance to deform under shear stress. In order to fine-tune the needed viscosity for the binder, several manual tests were performed using different glue and water proportions.

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2.III Simulating material behaviour By conducting a study of both the granular and viscous material used, at the physical and digital level simultaneously, an integrated design approach was achieved. The abstraction achieved through this mix of tools, yields insight into structure, material and manufacturing, allowing for very adaptable information. While manual experimentation relies on controlled variations to get to common system parameters, the digital experiments work inversely.

In addition to the initial simulations, the parameters obtained from the manual and machine experiments may at a later point be fed into these simulations. By doing this, the digital realm truly offers the opportunity to explore the unknown possibilities based on what can be tested by hand.

The first step of digitalizing naturally occurring systems, is to translate their behaviour into a set of rules. By defining these rules, the particles created in the digital world can be told what to do at all times and in all situations. In this way the response of the particle in relation to its environment, is simulated digitally.

Falling sand grains self organize according to cellular automata rules. By translating these rules into a 3D grid, particles released into this grid fall, and arrange themselves in piles, as sand grains in reality would. This simulation was brought one step closer to reality by having sand grains drawn from the surface simultaneously to them being piled. Both the gathering as also the depositing of sand by the machine is simulated in this way, using a programming software called processing.

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Cellular Automata Code

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Relative coorcinates of Nozzle1 and Nozzle2 on a flat surface x1=10 y1=10 z1=10 x2=10 y2=10 z2=0

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Application on an inclined topography

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Binder_ Leg control

Control of the number of legs, that is making different densities on a single pile was parametrized in grasshopper and total control of the position of legs was obtained.

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Real Flow simulation

After the sand piles had been created, a subsequent simulation allowed us to visualize the paths chosen by a viscous liquid falling on the peak of these already formed sand piles.

This flow of the glue on the sand piles was simulated in real-flow software and imported to rhinoceros with real-flow importer.

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2.IV Manual experimentation Figure 1

Figures 2 & 3

One of the experiments that contributed to a greater understanding of the binders properties was the testing of the influence of variations in viscosities. The higher the viscosity, the less it can penetrate into the sand’s surface. The velocity with which the glue trickles down the surface depends both on the viscosity as also the diameter of the binder nozzle.

Thus, the higher the viscosity of the binder, the more time needed for its deposition.

In order to define the minimum structure possible with a certain nozzle diameter, the vanishing sand experiment was set up. In it, 100ml of sand was used in consecutive sand piles by extracting the loose sand after the setting of each structure and depositing it in a new pile to be used in the next structure. This process was repeated until the minimum pile was created.

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Glue and sand combine to create a composite construction material that is solid, yet moderately elastic. As the final constructions are monolithic, this elasticity is of great importance as it allows the construction to redistribute the internal forces by deforming under loads. In addition, the structural design set up allows for the creation of as many column like legs needed. By increasing the number of legs, the axial forces are diverted over a shorter distance, causing less bending moment, and of course the forces in the structure are spread over a larger area.

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2.V Workflow It is only with all the machine elements working in sync, that the physical potential of the structure can be assessed.

After the manual exploration, the task at hand was to translate the characteristics revealed into parameters and with these, recreate the sand pile formations and the pouring of the glue with a machine.

Of influential importance is the self-organizing behaviour of the sand grains, the viscosity of the glue, the size of the glue stream, and finally the amount and the speed at which the glue is poured.

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Within the laboratory setting, this was done by programming the machine available at the investigation laboratory, the shopbot.

Firstly, only the configuration of the sand piles and glue deposition points were controlled through the use of the shopbot. The sand and glue valves were opened manually, allowing us to focus on the successful translation of the pat- terns. The next step in the machine development was the creation and configuration of the sand and glue pouring devices.

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03 Machine A machine placed on site will commence construction by rearranging the Sandy environment. In order to create a mechanism that is able to vacuum sand, the following basic components are needed: an intake port, an exhaust port, and an electric motor. Together, these elements produce suction by creating a pressure drop. Conventionally a motor produces an electric current which is used to turn a fan, drawing air into the machine and causing the air pressure in front of the fan to increase while the air pressure behind the fan decreases below the ambient pressure.

Although the fan sucks, it is positioned away from the opening, so that the particles aren’t transported through it. On its way through the machine, the air streams through a tube to a wider area, when it reaches this larger area, the air stream slows down, causing the particles carried by the air to drop and collect.

The depositing of the sand, as also the pouring of the glue, relies on the force of gravity.

However, less preciseness is needed in order to position the sand, simply opening and closing a valve can direct a sand stream towards the correct location. The size of the opening and the time span in which the sand valve is left open will determine the size of the sand pile. In order to pour the glue, a more precise nozzle is needed. Due to the impact small variations in the design of this nozzle can have on the outcome of the structure produced, the calibration of the nozzle specifications is a crucial part of this project.

The integration of sensors that scan the topography, allow the machine to be programmed with the basic intelligence needed to function in an environmentally conscious way by adapting to its surroundings.

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3.I Nozzle protyping With respect to the nozzle, both design considerations, as also control factors need to be carefully considered in light of the impact they will have on the resulting structure. We commenced the fabrication of the machine components by fabricating a customized nozzle.

The two most important design considerations are the nozzle aperture and the offset between the two nozzles. When a stream of falling sand forms a pile, the diameter of the tip of this pile is limited according to the diameter of the nozzle. In other words, the smaller the nozzle aperture, the smaller the minimum pile which is able to be made with it.

One needs to therefore calibrate preciseness against speed in function of the size of the pile needed. The required precision as also the ideal height of the sand nozzle is dictated by the size of the piles. Nozzle control is all about timing as the length of time the nozzle is left open determines the volume of sand released.

As the height of the nozzle affects the collision of the sand grains, there is less control on the formation of the sand piles with increasing height.

The sucking nozzle absorbs sand at a rate which depends on the speed of the fan, however, its position needs to be controlled as it needs to continuously lower itself to remain close to the surface.

The glue-depositing nozzle is a finer and more controlled nozzle. Control is needed with respect to its 3D position, which will depend on the amount of deposition points. When designing the height from which the nozzle is to deposit glue, it is important to take into consideration that the speed at which the glue hits the sand surface influences its penetration depth into the sand pile.

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3.II Prototype I Type: Static, not attached to the shopbot Aim: To explore the binder leg formation by controlling the number of glue trajectories Nozzle 1: Manual, fixed deposition Nozzle 2: Manual, calibration of deposition Result: Various static nozzles can be replaced by a single, moving nozzle, able to create a number of legs by moving over the deposition points.

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3.III Prototype II Type: Static but attached to the shopbot Aim: To configure the binder leg formation by exploring the glues natural flow Shopbot: Coordinates are extracted from a design made on a grid, and are given manually Nozzle 1: Attached to the shopbot, deposition occurs manually Nozzle 2: deposition and displacement occurs manually Result: Experiments show that when the speed and rotation of the deposition is fixed, in 63 per- cent of the cases the natural flow of the liquid forms three legs.

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3.IV Prototype III Type: Static but attached to the shopbot Aim: To adjust nozzle 2 and to deposit glue only at deposition points Shopbot: Deposition points from the grasshopper model are transferred to the shopbot through G-code Nozzle 1: Displaces itself to deposition points, deposition occurs manually Nozzle 2: replaced by a valve and attached to the shopbot, deposition occurs manually Result: Automation of the sand formation requires both nozzles to be controlled simultaneously in a sequence of fabrication steps performed by the shopbot in accordance with an arduino input.

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3.V Prototype IV Type: Attached to the shopbot and programmed by a processing file Aim: To deposit the glue along the glue paths of the legs Shopbot: Deposition paths from the grasshopper model are transferred to the shopbot in G-code Nozzle 1: Calibration of the nozzle offset Nozzle 2: Control through a grasshopper script of the opening and closing of the valve on certain paths Result: The fabricated result deviates from the uniformly designed structure, this positive breach of monotony, would have to be optimized with further research

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04 Shopbot experiments In order to unite the material with the project concept, a machine, suitable to the intended environment is needed, an autonomous machine, able to work on site and create the type of structure foreseen. Each task at hand can be performed by an individual element and combined, these elements shape the machine.

The key then is to gain control over this machine so that each part of the machine works in sync with the other.

Two parts come in to play, the transferring of information from the designers computer to the machine, and the intelligence of the machine to adapt this information according to the environment it finds itself in. It was possible to perform the first step in the laboratory.

In order to experiment with the recreation of our structures in the shopbot, the coordinates of the configurations needed to be fed into this computer. By extracting the coordinates from the digital files, these could be used by the shopbot to recreate the designed patterns.

The key to the intelligence of the machine will lie in connecting environmental sensors to it.

In order to make the machine truly autonomous, alternative sources of energy provided by nature need to be harvested. Solar and wind energies are excellent sources of these.

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Figure 1 The pile coordinates sent to the shopbot. The overlaying layers are shown in blue.

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“All processes whether they are produced by human efford or occur spontaneously in nature, can be viewed as computations� according to Stephen Wolfram.

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05 Geometrical Catalogue After being investigated separately, the machine expertise and the material knowledge needed to be brought together. With the aim of scientifically documenting the resulting structural findings, the results were catalogued according to the various material and fabrication parameters applied to them. To this end, the involved parameters were varied in a controlled manner.

During a thorough investigation of AREANAs geometries, these were explored on three levels: the micro level, the meso level and finally, the macro level. A different analysis tool was used at each of these levels. At the micro level, a sandbox, as done by Frei Otto, was used to investigate the minimum piles, single sand piles that form the building blocks of the structures geometry.

Next, the meso level deals with the effects the possible combinations of the minimum piles.

The effects different combinations can have on the larger, fractal pile, was tested by scripting them in grasshopper. Finally, at the macro level, the landscaping of the environment done by the machine was explored with the help of the programming language processing.

The catalogue aims at grouping structures according to the common parameters they share, in order to facilitate the extraction of the rules of behavior of the structural design system as a whole.

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5.I Sandbox of a radial apparatus Frei Otto’s Sandbox experiment is a cunning combination of simplicity and great value and was therefore repeated during AREANAs investigation.

With it, the first manual results of both the sand piles as also the resulting negative cavities were achieved. The systematic approach facilitated by the sand boxes allowed the manual models to be easily controlled by anybody to a greater degree. Firstly, the apertures in the top box were organized as a fractal patterns. During the pouring process, variations were made in the order in which these apertures were opened. Only a uniform process was possible with the fractal sandbox, as all components of the apparatus were connected in a stepped procedure.

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5.II Sandbox of an hexagonal apparatus In additional to a fractal pattern of apertures, a hexagonal pattern of apertures was tested.

The hexagonal patterned sand box allowed for very varying formations to be produced as all components were able to be manipulated separately. It is a very basic, manual form of parametric design in which the fabrication process is central. The shapes emerge from real time input which alter the parameters of the fabrication process.

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5.III Leg control_Small scale

By depositing binder on the peaks of micro sand piles placed in different configurations on top of the fractal, a variety of geometries can be superimposed on the overall structure.

Systems of wavy and linear crests between 0.5 centimeters to 25cm are formed, with the number of “legs� varying from 3 to 6. Depending on the configuration and number of legs, the resulting angles are 60,45,75 and 30 degrees. It is the variations, which are possible by altering the parameters which have been catalogued. Many more variations are possible through the overlay of the these geometries on the existing surface of the fractals. In addition, this method of overlaying may be used to increase the density of the structure and increase its stability.

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3 legged structures with the same direction of legs

with mirrored direction of legs

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with mirrored direction of legs and rotation

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combination of two differnt scales

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multiple combinations

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4 legged structures displacement of pile size

more dense by moving half distance

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rotated 90째

combination of two scales

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combination of two scales

combination of two scales and rotation

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5 legged structures

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6 legged structures

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5.IV Fractals_ Medium scale Benoit Mendelbrot first coined the term fractal in 1975. He used this term, to give a mathematical explanation of geometries that possessed a property called self-similarity (i.e.

Kochs curve 1920). The definition he gave of a fractal was “a rough or fragmented geometric shape that can be split into parts, each of which is (at least approximately) a reducedsize copy of the whole,� (^ Mandelbrot, B.B. (1982). The Fractal Geometry of Na- ture. W.H. Freeman and Company. ISBN 0-7167-11869.) Fractals provide a mathematical answer to many of natures formations, helping us to understand the way they grow.

The geometric understanding of nature is related with the precision and scale from we observe it. Increasing the zoom we discover new details defined by the topological rule. For instance, if we want to measure the surface of any sand formation, the resulting amount will depend of the ruler we use. So if we use a very small one that can measure the surface of a single sand grain we conclude that is unmeasurable or infinite. With fractals we propose a rugous model of material and geometry, in view of the smooth concept used until then.

The topological order in the sand formation is based in grouping grains of sand in piles, where the only restriction is the formation angle. With an additive process we configure different formations where the binder is forced down by a certain path under the force of gravity, solidifying the sand.

To understand the geometrical design of Areana we must keep into consideration the observation from different zoom factors. They will become different or similar according to the scale from we observe.

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Generating the code

The fractal can be scripted into a parametric grasshopper definition. Using this definition, the parameters of the fractal piles can be controlled, producing both visualizations of the resulting structures as also a G-code with the coordinates of the material deposition points needed to create them. The additive system scripted consists of 35 individual micro piles, which may be added to the surface of the big, central pile.

Variations in the uniformity of patterns, height, radius,scale,density and shape typologies were explored.

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Structural Behaviour Structural Behaviour The Areana system is not scalable in terms The Areana system is not scalable in terms of of material. The sand grains don’t grow in material. The sand grains don’t grow in size size with the scale, but however, the with the scale, but however, the geometrical geometrical design can be extrapolated in design can be extrapolated in different scales. different scales.

In order to grow in scale, we studied the In order tobehaviour grow in scale, studied the structural withwe mechanic tests and structural behaviour with mechanic analysis with software based in the tests calculation and analysis with software based in the by finites elements. calculation by finites elements.

The main conclutions that we can extract from Theanalysis main conclutions that we can extract the are : from the analysis are : The shaped structure of sand, previous to Thebinder shaped structure of sand, how previous to the deposition, shows the most the binder deposition, shows how the stressed areas are in the intersections, where most stressed areas are(figure in the 2). the binder flows down intersections, where the binder flows down (figure 2).

The solidified sand has a elastic behaviour

that allows us to be away from pure compreThe (figure solidified hascan a elastic behaviour sion 4).sand So, we produce figures with that allows us to be away from pure different section even out from the arch, like compresion (figure 4). So, we can produce straight and parabolic sections. figures with different section even out from the arch, like straight andthose parabolic The most stressed zones are that hold sections. the weight of the hole structure, it is mean the closest areas to the ground (figure 3). So, Themajor most concentration stressed zones of arematerial those that the must be hold the weight of the hole structure, is in these zones in order to support theitstress. mean the closest areas to the ground This restraints that the best formation is the (figure So, the concentration one that3). does not major increase the size in of lower material must be in these zones in order to areas. support the stress. This restraints that the best the one we thatchoose does not So, forformation big scaleisfigures, a system increase the size in lower areas. where the distance between intersections is uniform. Also, this distance is the one beSo, forthe bigstructural scale figures, weofchoose a sand. tween veins solidified systemthe where the distance Where structural needsbetween are controled by intersections is uniform.

Also,formation. this distance the densification of the sand is the one between the structural veins of solidified sand. Where the structural needs are controled by the densification of the sand formation.

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Figure 1. Densification control of sand formation.

Figure 1. Density control of sand formation

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Figure 3. Simplification of solidified sand structure and Von Mises Stress diagram (most stressed area in red).

Figure 4. Diagram of stress and deformation (elastic behaviour of the structure)

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figure 1 and 2 represent different densities on the same formation by doubling the subdivisions of the outer circle figure 3 the vaccumed part that creates the inner vacuumed part reaches the ground and the pile is subdivided

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Figures 4,5,6 show different densities of the same fractal by multiplying both the subdivision points and the concentric circles.

The subdivisions can be uniform or non uniform.

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Figures 7,8,9 show the different curvatures of the overall. Height and the radius define the angle of the fractal, thus its curvature.

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Figures 10,11,12 show the deformation of the formation,by changing the densities and creating inner densities.

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5.V Machine_Large scale

At the macro level, the interaction between the machine and material behavior in relation to the landscaping of the environment is investigated. To this end, both the positive sand piles, as also the negative holes produced by the vacuum mechanism of collection, were depicted in the programming language processing.

The machine was simplified, being represented digitally by three circles: the machine itself, the vacuuming arm and the depositing arm.

In the simulation we study how are the patterns produced by an autonomus machine, and the relationship between the deposited piles (marked in green) and the vacummed piles (marked in red).

The different patterns obtained from playing with the simulation are restrained by parameters, like progress, rotation angle and piling volume step. And, as other definitions explained before we produce a Gcode with coordinates and size of the hole system. Then, these pile formations are the base for the fractal system.

So, with this method we can arrive to basic patterns that can be processed in an additive way by computation.These patterns were grouped according to their nature: radial, linear or freeform.

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06 Application

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“Nothing is built on stone; all is built on sand, but we must build as if the sand were stone�

Jorge Luis Borges

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6.I Application

Rather than a final product, AREANA has resulted in a production method. A carefully designed tool which adjusts its fabrication process to any sandy environment. AREANA’s structures may take on a multitude of formations, evolving on site from the synergy be- tween the engineered process and the existing environment.

Although applicable to various sites and scenarios, the composition and fabrication process lend certain characteristics to all the resulting structures.Their temporary nature makes them suitable for events and seasonal activities.

AREANA’s most important advantages are the fast and low cost production method. The material acts as a mould to itself, therefore its cost can be estimated to only 1€/m². Additionally, since it is all sourced onsite, the transportation costs are eliminated making it an economically and environmentally sustainable design solution. Depending on the topographic, geological and environmental conditions the various emerging geometries can be distinguished into large and medium scale. In a nutshell the method can be defined as a “real data design process spanning over a long time”. This visual product is translated into a g-code, meaning a sequence of computated point coordinates that can be directly fed into the machine.

AREANAs applied structure, was tested through a comparative and empirical process.

We implemented the “Scan and Solve” computational software that is based on the finite element method. The software generated calculations which would then be compared to the physical testing of the structure.

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At this point it is important to note that the temporality of the structures is subject to the used type of binder and can therefore be adjusted to the needs of each situation. Lab testing has shown that the structures would become more robust when different kinds of binders were applied.

Regarding, the scalability of the structures three hypothetical case studies will be outlined for an existing area: facade panelling, shelters for emergency situations and structures for special events. It is important to point out that all the above case studies represent applications with a short lifespan.

Case Study 1 Location: undefined Type of building: prefabricated Purpose: faรงade paneling Case Study 2 Location: Erfoud, Morocco Type of building: Multipurpose space Purpose: Structures on locations without infrastructure Case Study 3 Location: Touristic beach Type of building: leisure space Purpose: leisure, events

In more detail, the three case studies are transportable panel system based in parts that is produced in laboratory, accessible places where any kind of scale of intervention can be profitable, and non accessible places where only a large scale intervention can support the transportation of the machine.

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6.II Case study I

Location: undefined Type of building: prefabricated Purpose: faรงade paneling Produced in a factory setting, the pre-fabricated faรงade panel elements can be mounted onto a number of different buildings. The textured panels form a second skin around the building which filter the sunlight and can aid the thermal insulation of the building.

Perforated panelling can be produced in the laboratory and the design will emerge from the combination of optimising time of production, space occupation, customised solutions for specific needs and a designed assemblage of parts.

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6.III Machinic Generative process

The following diagram represents how the final design is affected by the enviromental data scanned by the machine.

A gcode is transmited into the machine, that modifies the initial design according to data, like wind direction or solar incidence, and the presets stablished in the computational definition.

The design is reviewed after every formation, and affects the sand and the binder deposition.

1. g-code

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2. machine

3. scan

4. sand form

5. scan

6. binder dep

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6.IV Adaptation

With an adaptation process we can integrate different components in an existing industrial machine, taking advantage of the industry for our purpose.

The industrial machine used for adaptation is a retro-excavator used in market. The main transformation is given by an extra arm, obtaining then, the two arms machine required by the system. Other components of the addition are the vacuuming system, nozzles for material deposition and scanners.

With a low tech procedure we make the first autonomous machine for the system. Once that it is evolved other machines will be fabricated with a specific design for the process.

Deposition nozzles PiezoElectric Sensors Tracked Movement Data Processor Binder Container Pumb

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R x

y z X Y

Desert World Map

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6.V Case study II

Location: Touristic beach Type of building: leisure space Purpose: leisure, events Placed in an accessible sand location such as a touristic beach, our sand structure would especially benefit from its unique aesthetic qualities.

Able to be deployed rapidly, the temporary structure could serve as a party venue, house a market or be used for a number of other leisure activities.

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figure 1

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6.V Case study III

Location: Erfoud, Morocco Type of building: Multipurpose space Purpose: Structures on locations without infrastructure Located in the dunes close to the Moroccan settlement Erfoud, at the Algerian border, case study one is intended as a multipurpose space. The characteristics of our production process and material choice allow our structure to be erected in this remote area.

Intended to serve the needs of the indigenous nomads, the space can be used for various and varying purposes.

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07 Configuration techniques The material system of the research pointed certain configuration techniques in a both constraining and fruitful manner.While the fabrication process dictated rules conserning issues like scale, solifidication time, extraction method, the material possibilities were a fertile ground for exploration.

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7.I Arches and Sections

Through the creation of arches, a greater height is achieved in the intersections. The arches are produced by depositing the glue in a linear manner in transversal direction at the intersections of the piles.

figure 1

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7.II Layering

By layering the configurations, the density of the structures is increased and the internal forces are spread over a larger surface area.

Perforated panels can be produced with this technique.

Figure 1 detail of a model Figures 2,3 different grid configuration of layerings.

figure 2

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7.III Vacuuming

Figure 1 shows the grasshopper model of a vacuumed fractal formation Figure 2 Shows how by both vacuuming from the center of a pile and depositing a certain amount, the amount the piles do not intersect.One pile peak is now split into two peaks Figure 3 Vacuuming from the center of a pile and depositing on the inclined surface and overlapping one pile with the other. This procedure is repeated for the desired number of piles.

figure 2

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7.IV Negative

Through the use of a sand box, physical models of the negative sand holes were obtained, revealing vital information about the glue pouring techniques they required.

The only way to capture the sand cavities is to pour the glue on the peaks formed by the cavity intersections. In this way the glue trickles down and collecting in the centre of the cavity.

Figure 1 Shown in red are the intersections of the cavities were the glue is poured, forming the legs, shown in black lines. In grey, the holes of the negative gather the glue, forming “valeys�.

figure 1

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7.V Micropiling

This technique is exploring ways of growing in scale constrained by the binder properties.

A way to overcome the problem of scaling the diameter of the legs was by depositing small amounts of sand on the intersections of the greater formation. This resulted in the distribution of the binder into two paths along the intersection.

Figure 1 shows the deposition of glue over the micropiles Figure 2 show the formatin before and after the micropiles

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08 Models

First experiments

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Arches and Sections

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First experiments

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Vaccuuming

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Layering

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Details

Layering

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