Gradient Acoustic Surfaces

Abstract

While acoustics is a critical part of building performance, acoustic surfaces are often not integrated into a room’s architectural language. Acoustically-performing surfaces are often considered separately or even applied post-construction on top of existing surfaces. This has numerous detrimental impacts including: material inefficiency, design incompatibility, and reduced visual and acoustic performance. This research proposes an approach that integrates acoustics, architectural design, and digital fabrication within one system. The experiments use methods of parametric design, associative geometry, FDTD and FEM acoustic simulations methods, and combines these with prototyping experiments and the development of a robotic fabrication system. The key finding is the development of the concept of the gradient acoustic surface: which we define as a single architectural tectonic system, that can perform as all three types of acoustic surfaces – absorber, diffuser, or reflector, where the acoustic performance coefficients can gradually change over the surface. Experiments were carried out through the development and production of a full-scale wall sample. Design, simulation, and fabrication workflows were developed and we outline these as well as the fabrication challenges we encountered with the robotic fabrication of a stacked-brick gradient acoustic surface.