Inventory: CAD for Medium Resolution Materials

Master of Architecture Thesis
MIT 2022

Advisor: Axel Kilian
Readers: Brandon Clifford and Caitlin Mueller

With commands like "extrude", "revolve" and "array", contemporary CAD software contains analogues to the machine processes and abundances of industrial mass-production. This produces an affinity towards the predictable surface of standardized building materials in the mind of the designer. Furthermore, by creating geometry that was not there before, such software suggests that the only limit on the material world is processing power or file storage capacity, obscuring the extraction, processing, transportation and waste necessary to physically realize said geometry. This poses a challenge as it becomes increasingly apparent that material circularity is paramount in minimizing the deleterious environmental impacts of the construction industry. Inventory offers an alternative to contemporary CAD software where the gap between digital models and physical constraints is vast. Rather than abstract commands that project forth a not yet existing material condition, Inventory is based on digital representations of specific pieces of material, sites, actions used in fabrication, and protocols for assembling parts.

A series of physical joints were developed exploring how dowels, bioplastic and rope could be combined to constrain pieces of irregular stock.

In order to adapt to material irregularities architects have adopted various 3D scanning techniques to produce digital representations of materials. By the nature of their discrete sampling, however, these representations vary in their precision. What the architect encounters in the 3D modeling software is not the material itself in its infinite specificities, with its weight, moisture content and smell, but rather a surface representation composed of a large but finite set of points. This surface might be called medium resolution. This research operates within the medium resolution surface condition, accepting it as a geometric paradigm necessary to respond to emerging material realities.

Inventory uses game engine physics to allow the designer to model with some of the constraints of physical making. "Actions" in Inventory are abstractions of fabrication processes that join parts together. "Protocols" are algorithmic patterns of interaction between parts that choreograph the composition of assemblies. Over the course of the thesis semester, several prototypes were modeled within Inventory and then fabricated using a custom robotic fabrication workflow.

What this research offers is not a design proposal, but rather, a proposal for how to design. Inventory composes architecture through the interaction of parts, sites, actions and protocols. Each category in its own way is an abstraction of the physical interaction between specific materials made possible by the medium resolution paradigm. Rather than the model forward practice of design that dominates today and which is predicated on trust in the availability of standard materials, Inventory establishes a dialogue between physical material conditions and digital models. As this final prototype represents, in inventory design and construction are not a one-way stream of information and materials ending as a file in a computer’s trash and a 2x4 in a landfill.