Integrated Design Models for Materially Differentiated Knitted Textile: Membranes as the Means to Sustainable Material Culture Within Membrane Architecture

Material design and production must be rethought in light of limited resources, contributing to UN Sustainable Development Goals, promoting sustainable industrialization and fostering innovation. Currently, building practices rely on composite materials to meet a variety of performance demands, by bonding different materials together. This results in problems of reuse and recycling at the end of life, as they are hard to separate. As an alternative, functionally graded materials (FGMs), such as CNC-knitted membranes, allow the steered intensification of a single material in order to meet multiple performance requirements and ease their further reuse. Current architectural design practice conceptualises matter as homogeneous, while novel FGMs, and knitted architectural materials in particular, require radically different methods and tools for their design and digital representation. Given their extreme heterogeneity, complex material behaviour prediction and additive manufacturing nature, there is currently no ready-to-use software to address these challenges. In order to improve the quality of taken design decisions, better reflect knitted FGMs characteristics and pave the way for more sustainable production using FGMs, it is essential to create integrated design models, considering material heterogeneity, structural performance and fabrication constraints of such materials. In this research, we examine how CNC-knitted membranes, having versatile material structures, can be designed with heterogeneous composition. It is done through the development of custom digital tools that reflect their differentiated structure, analyse tensile performance and perform materially oriented simulation, while taking into account fabrication constraints (figure below). We describe a novel approach to inform the differentiation of knitted membranes by structural analysis and a method for calibrating heterogeneous membrane simulations. By utilising computational tools for structural performance evaluation, Graded Knitted Ceiling panels demonstrate how custom-made bespoke membranes can be materially differentiated and how such designs can then be simulated and calibrated based on the physical results.