gramazio kohler research, an architectural robotic laboratory at ETH zurich, has improved the acoustic qualities of a cafe in switzerland using three computationally designed and built walls. with a total area of 90 square meters (approx. 970 sqf), the surfaces are composed of 8,500 identical fir timber blocks. to improve speech intelligibility, each timber block has a unique position and orientation based on the principals of the ‘schroeder diffusor’ — a structure comprising a number of wells of different, carefully chosen depths.

gramazio kohler cafe
perspective of wall B in the cafeteria
image © gramazio kohler research, ETH zurich (also main image)

 

 

the project was commissioned by basler & hofmann, and is installed within the engineering firm’s cafeteria in the swiss village of esslingen. due to the asymmetric cut of the front side of the blocks, their different orientations create customized shadow patterns on the wall, dynamically changing throughout the day. meanwhile, the varying gaps between the blocks improve the cafe’s acoustic absorption and function as air ducts for the ventilation system integrated behind the walls.

gramazio kohler cafe
shadow pattern of wall A
image © gramazio kohler research, ETH zurich

 

 

gramazio kohler research and the robotic systems lab at ETH zurich have developed an augmented object laying technology, which provides visual guidance for the builder to place blocks in accordance to a specified design. the carpenters are equipped with a custom-built camera controller unit, while feedback is provided via a monitor. the system recognizes and tracks objects and provides feedback on deviations between the built structure and the virtual design.

gramazio kohler cafe
AR set-up with acoustic wall
image © gramazio kohler research, ETH zurich

gramazio kohler cafe
shadow pattern of the acoustic wall in the cafeteria
image © gramazio kohler research, ETH zurich

gramazio kohler improves a cafeteria's acoustic qualities with computationally designed walls
shadow gradient in acoustic wall A
image © gramazio kohler research, ETH zurich

gramazio kohler improves a cafeteria's acoustic qualities with computationally designed walls
joint opening near the ventilation outlet
image © gramazio kohler research, ETH zurich

gramazio kohler improves a cafeteria's acoustic qualities with computationally designed walls
elevation of acoustic wall
image © gramazio kohler research, ETH zurich

gramazio kohler improves a cafeteria's acoustic qualities with computationally designed walls
wall A (left), wall B (back), wall C (right)
image © gramazio kohler research, ETH zurich

gramazio kohler improves a cafeteria's acoustic qualities with computationally designed walls
view from the cafeteria to the dining area
image © gramazio kohler research, ETH zurich

gramazio kohler improves a cafeteria's acoustic qualities with computationally designed walls
producing the polygonal section surfaces of the blocks
image © gramazio kohler research, ETH zurich

gramazio kohler improves a cafeteria's acoustic qualities with computationally designed walls
feedback-driven placement of one timber block on-site
image © gramazio kohler research, ETH zurich

 

 

project info:

 

credits: gramazio kohler research, ETH zurich
in cooperation with: robotic systems lab | ETH zurich, dr. timothy sandy
client: basler & hofmann AG
collaborators: matthias helmreich, dr. aleksandra anna apolinarska
selected experts: basler & hofmann AG, strauss elektroakustik GmbH
industry partner: erne holzbau AG
planning: january until may 2019
execution: may until july 2019