Digital Rustication

As part of ongoing research in the translation of ancient methods of making into contemporary processes, this project showcases the fabrication of a freestanding wall through the use of a multi-axis robotic arm fitted with a hot-knife in service of cutting expanded polystyrene foam into mass-customized and stackable blocks.

Toolmarks are imparted to the surface of the foam using a U-shaped hot knife. As the distance between passes increases, so does the roughness of the finish. Variation of toolpath travel results in a scalloping effect. The wall utilizes toolmarks as a method of surface approximation traditionally used in stone carving.

We used a 6 axis KUKA KR6 900 industrial robotic arm and fabricated all of our own tooling. To make sure that blocks of foam were roughed out with parallel edges, we used a bow-type hot wire cutter to make sure each side was squared up with its neighbor.

The wall is constructed of roughly 140 unique bricks, which are cut from four distinct block blank types. The cutting process enables precise shaping of components, enabling them to be placed side by side to form courses. These sub-assemblies are then stacked using a modified running bond pattern.

The wall is a hollow cavity, with the specific depth of block being determined by local features and overall global form. Minimum overlapping distances between courses are observed to create a contiguous finished surface.


Andrew Manto, Patrick Little, Naz Ekmekjian, Daniel Smithwick under the direction of Professor Brandon Clifford. The fabrication of this wall also includes collaboration with members of the MIT International Design Center.