ACADIA/FLATCUT Competition Entry

A few of us in the office put together an entry for the partition category of this year’s ACADIA/FLATCUT competition.  We made it into the group of finalists (despite formatting our boards incorrectly), but unfortunately we were not selected as the winner (probably because we formatted our boards incorrectly, only joking).  The competition put forth an interesting challenge:  use both rigid and flexible sheet materials to create an assembly (light, furniture, or partition) that highlights the properties of each material while minimizing the amount of waste.  Below are the images and text from our submission as well as the final boards.

Design methodologies are consistently prodded and challenged by emerging technologies. CNC tools have enabled us to fabricate highly intricate and irregular forms, but the results are rarely materially efficient.  Simulation-based form-finding has allowed us to generate geometry tuned to specific forces, but have the realities of material properties and fabrication methods become the key drivers towards optimization? This project seeks to integrate these two expanding realms within the contemporary design pursuit through the creation of a materially efficient partition system.

The overall geometric catalyst is a freestanding, double curved surface, creating both formal stability and a varied visual experience. The surface is generated from two horizontal Cosine curves swept along a vertical Sine curve, creating a doubly curved surface within a 2’x8’x8’ footprint.

A physical simulation is run on the idealized surface to find a developable approximation.  A triangular grid is applied to two 4’x8’ sheets of material whose edges are constrained to remain the same length. Another force pulls the vertices of the triangular grid towards the idealized surface geometry.  To reflect the realities of fabrication and material properties, the original edge length of each member is prioritized over achieving an exact match to the target geometry.

Thin sheet materials such as PETG are inherently unstable in compression when used in expansive, single surface geometry.  The secondary geometric catalyst addresses this requirement for structural rigidity through the amplification of surface depth.  The goal is to optimize a doubly curved tetrahedral space frame in order to generate structural rigidity from two 4’x8’ lightweight and translucent PETG sheets.

The partition is composed of three layers; folded tetrahedrons, links, fabric skin.  The material of each layer has a degree of translucency which reveals the entirety of the structural system from any orientation.  The effect is a diaphanous system that is enriched through the overlapping geometry of each layer.  Each material contributes a unique function to the entire system and their geometry was designed to limit the amount of waste generated during the cutting process.  Approximately 90% of all the original material is used in the final partition.

The depth of the partition is achieved through the use of two thin (0.060”) sheets of PETG that are cut and folded to create a set of tetrahedrons.  The unfolded geometry of the tetrahedrons are three interlocking arms that use all of the material within each triangular cell.  The cuts never intersect to create a closed shape so each sheet remains a single piece.  The tetrahedrons are greater in depth  towards the center of the partition, allowing the edge to seem very thin while providing the maximum stiffness in the center.

The overall form is achieved when rigid links are placed between the apex of each tetrahedron.  Each link is unique in length and tagged with an identifier corresponding to its grid location on the folded PETG form. To ensure compressive stability, the links are cut from of a thicker sheet of PETG (0.118”).

The final boards:

The winning design in the partition category had some really interesting strategies. Especially the use of no hardware, something we aspired to but were unable to achieve.