critical mass Integrating Material Scanning with computational form-finding

Dyani Robarge  |  fall 2016-spring 2017 thesis

 

Abstract

This thesis seeks to explore a renewed relationship between architecture and timber construction, wherein design decisions are informed by the material’s grown qualities. As an unpredictable building material, the constant feedback required between artist and material makes timber particularly analog in the way we design and construct it. Linking robotic carving to techniques of external scanning presents a yet-unexplored alternative to traditional ways of building with wood. My project will begin by collecting sections of the tree often discarded by sawmills (crotches, trunk sections with sweep, etc.) and scanning them to create a structural whole out of highly variable components. The nuances of each piece will inform the jointed connections of an overall form. I aim to use this innovative carving technique to experiment with material aggregations which push the boundaries of timber design and construction.

Project narrative

High variability makes timber an especially unique construction material.  Only recently has it undergone standardization as a result of industrial manufacturing. This processing of wood has resulted in architecture which is no longer reliant on, but adverse to, nuanced qualities of the material itself. I believe economy and optimization alone are not enough to produce buildings of cultural value. In an attempt to homogenize timber, architecture has lost a critical connection between builder and material.

Could the use of external scanning create new connections between raw material and architectural design? The emerging scanning technique of photogrammetry allows one to represent physical objects to an extreme degree of precision in the digital medium. External scans are already being employed by large-scale mills to allocate resources more efficiently. I would like to explore this question by linking external scans of wood to customized robotic tool paths. I will be implementing these first tests on wood crotches (the branching top portion of the hardwood trunk) because they are perceived as waste and remain unused by the logging industry. The resulting aggregations could converge with standardized lumber techniques or take on entirely independent new framing types. 

 

DESIGN SYSTEM:  Reality-Capture >> Analysis >> Configuration

Schematic design developed using form-finding script

Plan view of schematic design

Joint details showing part-to-part connections

 

11.07

Evolutionary Form-Finding: Case Study 04

Evolutionary Form-Finding: Case Study 04

 

10.24

Mass customization, by nature, breeds highly specific building components. Traditionally, digital fabrication extracts these bespoke components from large, standardized sheets of material. Evolutionary form-finding enables the designer to reevaluate this workflow by reversing the design process. Similar to mass customization, this method results in highly customized joinery. But rather than cutting planar sheets to achieve non-planar results, generative form-finding seeks to optimize form based on available components. The evolutionary solver searches for possibility within given restraints. Form-finding is an adaptive process:  at each iteration, the system evaluates itself based on its author's desired parameters. The results are irregular and somewhat foreign .

Evolutionary Form-Finding: Case Study 01

Evolutionary Form-Finding: Case Study 01

My research is rooted in the exploration of building with nonstandard parts. The capability to map objects in virtual space allows architectural design to expand beyond working exclusively with highly-processed materials. Standardized construction is no longer the most economically-efficient means of design. As technology speeds towards efficiency, computational tools have begun to aid not only the representations of architectural design, but the generative processes as well.  This method asks: given an array of highly-varied objects, what are the built possibilities? 

Considering the issue of how to derive design through computation, it is a question of how (and if) one can elicit new sensibilities through rule-based systems. Michelangelo’s contempt for textile weavers was widely known; he considered them to be at the bottom of the hierarchy of the arts, because he considered their work to be repetitious and unthinking. It is much easier to find the rules for objective performance than for intuition or serious cultural production. It is absolutely possible to derive mathematical formulas from a Mozart sonata but debatable whether you could run the process in reverse and come out with a Mozart.
— Jesse Reiser & Nanako Umemoto, The Scent of the System

10.14

Processing of material scanning, analysis and translation to robotic carving toolpaths

Branching assembly diagram showing 'nodes' as drivers for branching connections

Method

My early research will focus on ways of incorporating waste produced by the timber industry into architectural components. In the process of harvesting logs, both for profit and public service, virtually all of the tree is allocated. Log sections too large for the tree chipper (typically larger than 12” diameter) are piled outside and gradually picked off for firewood. The remaining becomes compost, eventually decomposing back into the earth. In terms of utility, they don’t provide much. Log manufacturers and those in the construction industries have yet to realize a potential for these discarded pieces. 

I plan to scan a range of species and forms within the first case studies to create a series of material case studies. I plan to build off these material studies in the second round of scanning, wherein I target a specific selection of tree forms which have branching qualities most suited for structural purposes. In this second round of scanning, I’ll link the 3D scanned models to tool paths for carving the pieces. This carving method will be informed by the aggregation of parts created by form-finding evolutionary processes. As an artist, this process will allow me to design structures which allow the unpredictable natures of the timber elements to express themselves through specialized forms.

 

10.01

The pursuit of this thesis is focuses on architectural expression over structural optimization. The construction pieces I've found are often left by loggers in the forest to decompose. Up close, these abandoned fragments of tree bear closer resemblance to found objects than an under-utilized industry resource. This quality reinforces the project's desire to refine our understanding of physical properties lying dormant in the surrounding environment which often go unnoticed. It hopes to reveal hidden architectural potential within atypical materials. This unpredictable, highly-varied nature is what makes wood an intriguing subject to work with. 

The grown qualities of an area’s stock of wood are fundamentally tied to regional climate. Climate shapes a forests’s makeup both in terms of species and spatial density. Pennsylvania’s vast amount of wooded area yields a higher timber production than most other states and is steadily increasing. In 2015, the Forest Inventory Analysis Program reported a continued, steady increase of available timberland. But Pennsylvania is no anomaly. In fact, this figure reflects the larger, national trend of forest land across the states. The region is effectively surrounded by this readily-available, easily-renewable construction source. This biological trait, in turn, drives economical use. To gain better insight into the specific qualities of available materials, I took a closer look at the local PA timber industry and surrounding forestry. 

The words grain and figure are often used interchangeably. In actuality, figure is a more detailed description of wood’s appearance which often is directly tied to species grain and other distinctive qualities. Grain refers to the pattern of rings revealed by sawing, whereas figure is shaped by the oddities in growth and arrangement of wood. These unusual qualities produce effects such as curly, bird’s eye, feather, flame, crotch, etc. Skilled woodworkers will carefully pieces based on these properties to create highly unique furniture and cabinetry. Due to the milling industry’s reliance on straight-grained roundwoods, these unruly sections of log are no longer desired qualities in our current manufacturing-based industry. 

Climatic region determines arrangement, composition and size of cells at the microscopic level. The Janka Hardness Test measures wood’s resistance to denting and wear. It’s measured by embedding a steel ball into a wood sample until the ball moves halfway through the material. The measurement of hardness is also dependent on grain direction. Wood is composed of natural polymers, mainly cellulose strands and a lignen binder. Because of the direction these strands run, wood is significantly stronger when stressed longitudinally (along the grain) than across it (radially or tangentially). The varying properties of wood with and against the grain make it naturally an-isotropic.

This diagram depicts the history of the form and mass of structural timber components through the ages.

 

09.21

Is the desire to preserve the natural characteristics within materials really about uncovering emergent behaviors which lead to new formal possibilities? Or is it a diametric response to mechanized processes of manufacturing, scripted design and digital fabrication? 

Alexander's notion of the loss of innocence asserts that agency is taken away from the designer by placing it squarely in the hands of economy. In fact, standardization and the use of computational design have become so deeply entrenched within the industry that they’ve actually begun to overtake it. 

Superwood by Gramazio & kohler, 2009

Superwood by Gramazio & kohler, 2009

In terms of the intellectual loss- the promise of the freedom afforded by computational design, although held captive by the restrictive representational techniques of earlier CAD programs, has finally begun to emerge... 

Enter parametrics: a method of workflow which favors designer-as-programmer has taken place in the form of scripted architecture. This, in turn, influences decision-making. But using computational modelling to work with extreme precision and hyper-specificity still encourages us to think, and build, as machines do. Even as developments continue to occur in fields of computation and design, the architect’s loss of innocence persists. 

This emerging design process must allow room for an artist's ‘intuition’ if it is to preserve cultural meaning within the field of architectural design. 

But perhaps there is a way to regain it. This answer can be uncovered by turning our attention back to the material makeup of our structures. At the most basic level, a restructuring of nature occurs in the translation of matter to form. As an architect (and also as a human being, dependent on this planet’s limited resources), I feel compelled to simplify this process- the most natural direction always points towards efficiency.

Building materials are a finite and costly resource, a principle not unlike that by which biological systems in nature make use of their own resources.
This notion is summarized in the recognition that in biology, material is expensive, but shape is cheap, whereas until today the opposite was true in the case of technology.
— Achim Menges, Manufacturing Reciprocity

Could we use the ability of available scanning techniques to sculpt based on the intricacies of raw material structure?

Although this sounds like a wildly radical idea to the construction industry, it’s already proved effective in other specialized interests such as large archaeological sites and stone quarries. In fact, the scanning techniques have proved a useful tool to inform milling operations within the logging industry for well over a decade. The raw, roundwood log itself is not an easy or outwardly beautiful object to work with. It must be wrestled by tool and craft before it begins to take form. 

Laser scanning of a copper ore quarry in the Middle Urals, Russia. This image is a point cloud of the open cast. Image by Trimetari Consulting.

Laser scanning of a copper ore quarry in the Middle Urals, Russia. This image is a point cloud of the open cast. Image by Trimetari Consulting.

By utilizing the underlying natures of our building materials, we can create more attuned environments while reducing the industry’s unhealthy reliance on costly manufacturing processes. This use of digital scanning is able to merge seamlessly with the parametric workflow, allowing for a fluid transition between data sets. I'm also interested in exploring ways in which the artist is able to 'sculpt' the material into unique building modules or as larger forms into the site using these processes of material analysis. 

 

09.16

Zooming back into the inner workings of our buildings, we see complexity increasing at all levels of built production- even the individual unit itself. In contradiction to standardized units. aggregations of pieces now require each to be different.


Parametrics allows for material aggregations to facilitate a flow of forces and seamless connections between forms. Transitions between disparate elements become smoothed. Through parametric modelling, the input of design solution parameters such as shapes, environments and desired qualities are reduced to a single workflow. The system relies on an inter-connectivity of parts. Because of this quality, working parametrically has resulted in forms which take on similar qualities of fluidity.

In The Architecture of Error, Francesca Hughes observes the flow of data within parametrics as having a tendency to result in material (component) aggregations which facilitate this flow of forces. She notes a parallel between material negotiating forces through its form with that of poured concrete. 

Technological advances and the increasing complexity of data now available to us as designers has shifted design workflows to rely heavily on computational systems. We should embrace these changes as a necessary leap within the evolutionary path of the design process. Christopher Alexander, an early pioneer of rule-based design systems, goes beyond merely suggesting this approach to designers: he believes it necessary for the continued growth of design itself. In Notes on the Synthesis of Form (1962), he argues our technology is evolving at a pace which requires us to use systems logic: man's cognitive abilities can no longer keep up with the complexities of our world. 

Equally important (and less recognized) is his realization of the human factor within systems as critical to architecture of cultural value. But at what level can computation facilitate design decision-making while still allowing intuition to take place?

The use of logical structures to represent design problems has an important consequence. It brings with it the loss of innocence.

There has already been one loss of innocence in the recent history of design; the discovery of machine tools to replace hand craftsmen.

Now we are at a second watershed. This time the loss of innocence is intellectual rather than mechanical. But again there are people who are trying to pretend that it has not taken place. Enormous resistance to the idea of systematic processes of design is coming from people who recognize correctly the importance of intuition, but then make a fetish of it which excludes the possibility of asking reasonable questions.
— Christopher Alexander, Notes on the Synthesis of Form
 
ShigeruBanQuote.jpg

This thesis argues our current building construction industry still has much to gain from the use of computational design within architecture's domain. This failure to connect the two is due largely in part to the difficulty of merging the digital workflow into existing methods of construction practice. Perhaps if scripted design had something to offer the industry, in terms of economical gain or a more efficient use of resources, this change would happen at a quicker rate.

The synthesis of computational modeling with digital fabrication allows for the quick creation of complex forms. But to apply these new techniques to the industry in the physical/material world requires understanding material behavior to a greater degree. This is why exploring the gap between digital and physical modeling will require a range of tolerances designed into the system itself.

 

09.09

Precision

Architectural forms are intricately linked to their tools, materials and the human hand. Inconsistencies lurking within materials means they are not entirely predictable... neither is human error. 

But the computer, arguably the contemporary designer’s most powerful tool, is one which relies on precision to an extreme degree of tolerance. 

In fact, this degree of exactness runs contrary to the human condition. It calls into question the traditional construction site, wherein room for error is built into the system of working. Although standardized are held to an absurd level of homogeneity, inconsistencies still occur. Precision is great when it works but one meticulous overall form can quickly be compromised by the accumulation of small inaccuracies. 

Hyperspecificity

Fabricating buildings via mass customization of parts introduces a degree of hyperspecificity unprecedented since industrialization of the modern era hit the building industry in the early nineteenth century. 

Within the design-to-production workflow, standardized parts are often utilized as components of the system but not integral to the overall form. Real-time scanning techniques help account for building with unique parts. Machine-learning through the use of feedback sensors is also becoming more prevalent within automated industries. 

Automation allows us to bypass these complicated and data-heavy working methods completely by forming material units in tandem with the construction process itself. 

Adding complexity to material configurations addresses the function of traditional building unit forms. In turn, this challenges notions of traditional materials and construction processes. Could restructuring our computational design tools create more effective ways of building complex forms?

A material’s inherent physical properties bias its behavior, structurally and formally. Louis Kahn once stated, “Even a brick wants to be something.”

In the era of working parametrically, does the brick still want to be a brick?

 

09.06

Within the translation of matter to form a restructuring of nature occurs.

Barbara Hepworth’s sculptural forms reveal a physical dialogue between the artist’s intuition and material’s behavior. The carvings are minimal and carefully selected. They seek to uncover the underlying, fundamental natures between the two bodies- woman and stone. As the material’s latent behavior revealed itself to Barbara, she found that deviating from the stone’s inherent properties created a sense of error against its natural state. 

The act of carving necessitates that form be derived from the innate natural properties of the material itself, but is not in complete control. Instead, there is a margin of error wherein the sculptor projects their artistic directions onto the object. 

How can this notion of the 'slippage' between material error and an artist's realized form be applied to architectural objects? Answers to this question require that the architect gain greater insight into material makeup and form. 

 

Curiously reinforced by the digitalization of practice and, more recently, of fabrication, the further belief that our control of matter might now, once and for all, be total is rendered tantalizingly close.
— Francesca Hughes, The Architecture of Error