A leftover piece of support scaffolding from a Stereolithography (SLA) build...This is probably one of the earliest recap projects included on this blog, predominantly realized in the Fall of 2002 - Spring 2003...
Preamble
Rapid Prototyping (RP) & Rapid Manufacturing (RM) are two of the terms (along with Digital Fabrication, Direct Manufacturing, Layered Freefroming, Fabbing, to mention a few...) used to describe a fabrication process in which a 3D physical object can be 'printed' directly from a computer file. What all additive Rapid Manufacturing processes have in common is that they are always fabricated through the gradual stacking of thin fabricated layers of material (that can range from plastics, to ceramics, to even metals) made up of slices from the original computer file.
An illustration of the slicing process (image from Wikipedia - Rapid Prototyping)...The accuracy of these fabricators are quite impressive, as many of them can make things at 0.05 mm size and resolution. This ability, however, also introduces its own problems, as at that scale, when making something that cantilevers out from a core (imagine making a letter 'T', or perhaps something shaped like a mushroom) it's becomes very difficult for the initial fabricated slices to support themselves, as their own 'dead weight' would inevitably cause them to bend or even break off before the cantilevering part becomes strong enough to support itself. To counter this problem the some of the fabricators* have added a feature in the fabricator's software which, when it detects there to be an overhanging feature, it automatically creates a fine scaffolding to support it. This scaffolding (an image of a piece of discarded scaffolding from the SLA process can be seen above) is usually removed when the fabricated piece is completed. However, this scaffolding has its own inherent intricate beauty that, especially when dealt with in larger chunks, is a true pity to scrap.
The images below are of a (quasi) design that explores these qualities of the scaffolding and uses it as an inherent component in a design - a small bowl where the scaffolding functions as the 'filler' material between the bowl's concave container and its base. The interesting thing (at least from a CAD perspective) is that in the design, the scaffolding needed to be considered, but could not modeled, during the design's CAD draw-up phase as the scaffolding is something that will only come about if particular conditions are met during the fabrication process that catalyse their production. Instead, what became important was to design, and consequently define, how the bowl should be positioned and orientated in the machine during its making so as to allow the scaffolding to 'grow', and fill up the intended areas between the bowl part and its base. This was achieved by defining the design's two components as a single object whilst still setting them apart. This process was also aided by linking the two bowl components by a set of 'hypothetical strands' - fraction of a millimeter thick beams which only existed within the CAD model, but which nevertheless allowed the design to be read as a singularity.
A screenshot of the bowl's Rhino model...Two version of the bowl were made, one using Stereolithography, the other using a slightly different Rapid Manufacturing technology called Fused Deposition Modeling (FDM), which distributes and layers the material in a strand format (a bit like squeezing the material out of a tube of toothpaste). In the FDM process two materials are distributed, one the actual build material (usually a white ABS plastic), the other a support material that can be 'washed away' when the build is complete, but, in this instance, left as is. Examples of these two renditions can be seen below. What is remarkable when comparing the two bowls is how different they actually are. They were both fabricated from exactly the same CAD file, yet, due to the different output fabrication methods used, the results were two very dissimilar designs.
The SLA version of the bowl...
The FDM version of the bowl... Materix, Avaterial & Metature...
Continuing on the train and process of thought outlined above a 'what if' query reveals itself. As it stands, the scaffolding produced by the SLA method is a generic and default entity that, even though unique in the sense that it is particular to a very specific technology, does not have a purpose once its role as a support structure during the fabrication process is fulfilled. However, what if it did? What if the scaffolding acquired, in a sense, a brain? What if the make up of the scaffolding wasn't uniform, but could respond, or be adjusted, to accommodate a variety of different purposes through altering the set up of its structure? A form of dynamic, self adjusting, homeostatic system that would adapt itself to the existing conditions or defined circumstances (the functions) by, at the minute scale the additive CAM technologies allow for, conform the tectonic make-up of its scaffolding to provide an optimized response. A micro-structure that (when paraphrasing Louis Kahn's famous dictum) would not only, when considered in the context of architecture, allow one to ask, "the brick what kind of building it wants to be", but apply the query at an even more primordial level where the clay can be questioned regarding what type of brick it wishes to become. Here a single material could be used which, through manipulating its structure at a micro scale into a number of different tectonic configurations, could be given different physical and sensory properties - a design could be made light and malleable at one end, and gradually transcend to become more rigid and solid at the other if needed. Here the potentials of construction would almost solely be limited by the parameters of ones imagination rather than the more common collage assembly of materials, structural units and constraints.
The RM technology allows one to create bespoke micro tessellated structures which can be adapted to provide a variety of different physical and textural properties... To allow this to happen individuals with the appropriate programming know-how were needed. A worldwide search was conducted, from Oslo to Ohio, scouting for expertise at institutions of higher learning. A willing set of collaborators were eventually found in London, the project's own backyard, at the University College London (UCL) where Dr. Peter Bentley, author of the then recently published book dealing with seemingly related subject matters, titled 'Digital Biology', was a lecturer. It was Dr. Bentley who suggested that some of his current grad students might be interested in collaborating. For the following six months or so, with the aid of Jamie O'Brien, Sean Hanna and Siavash Haroun Mahdavi, we debated, speculated, rationalized and conceived the initial means and logistics regarding what realizing this adjusted paradigm of designing something might entail. The latter two, Sean and Siavash, eventually published a well received paper on the more technical and programming related aspects of project, based on which Siavash, once completing his PhD on this very same topic, went on to establish a company called Complex Matters (in collaboration with UCL) which re-formulated the venture as a more commercial enterprise. Examples how how these ideas can be formulated from a design perspective can be viewed in earlier submissions to this blog.
An example of the initial SLA Avaterial Materix build... The terms referred to in the title - Materix (Material-Matrix), Avaterial (Avatar-Material) and Metature (Meta-Architecture) became neologies, or portmanteaus, eventually used in the context of related projects to describe different facets of such constructs. Materix is a generic term used to depict the tessellated mesh of these systems. The word Avaterial is used to distinguish a particular type of Materix which is more of an intermediate, more graspable and handleable scale. Metature purports similar aims to Avaterial, only in this case identifying something of an architectural scale and volume. These terms have developed in conjunction with this still evolving fabrication discipline - in which everything still seems new, challenging and exiting. What it entails, what type of design it will allow for, and the methods through which related designs will be realized are still in the process of being formulated. The future for how these technologies will be utilized to fulfil our needs is ours to define...
Two examples of a Materix Avaterial - one a 75 millimeter, the other a 25 millimeter cube which, even though in this case being a scaled rendition of the other, have very distinctly different physical properties... * Some of the fabricators do not need to worry about this problem as they make their builds into a powder-bed of the fabrication material, that automatically supports such cantilevering features...
No comments:
Post a Comment