From Stitches to Digits and Back: Computational Crocheting of Branching Geometries

Abstract

Crocheting is a hands-on craft that involves repetitive manipulation of a single continuous thread with a hook-like tool to generate surfaces and 3D forms. In a previous study, we have presented a parametric model [1] that generates crochet patterns of NURBS surfaces using a 10-stitches-by-10-rows swatch to account for all the physical variables that affect the crocheted object (i.e., yarn thickness, hook size, crafter’s grip). The dimensions of the previously crocheted tension swatches were used as the inputs of the crochet pattern generator algorithm, alongside the desired NURBS geometry, to generate individualized crochet patterns. These crochet patterns are text-based representations, similar to g-code in additive manufacturing, enabling the documentation and communication of the step-by-step hands-on crocheting process. Following these crochet patterns, the users can crochet physical objects with the same dimensions and form as their digitally modeled counterparts. 
 This paper presents the second stage of this research in which we expanded this computational framework to enable crocheting of parametric branching geometries with multiple components by multiple crafters. While the components of the branching geometries can be crocheted by a single user, it is also possible to have different users crochet the components since the tension swatch can capture crafter-specific variables. As a proof-of-concept, a branching structure made of 14 unique components is designed and crocheted by two students of architecture as part of the Advanced Digital Fabrication course at the Pennsylvania State University. The students each crocheted 7 components based on their individual inputs while maintaining the dimensions and form of the digitally designed branching geometry. The findings suggest the possibility of a collective and distributed crocheting platform which can be used to create crocheted artifacts in various scales. This can be considered an alternative way to transition from the digital to the physical without relying on digital fabrication tools.