Towards the control of doubly curved active textiles through graded pre-stretching and 3D printing

The production of complex shell geometries with the aid of textile supports is of interest in various fields, from fashion design to architecture, and at various scales of application. Yet, digital fabrication methods addressing double-curved shells by means of pre-stretched textiles and 3D-printing currently lack solutions for systematically controlling the curvature of the fabricated components. We introduce two methods for activating and controlling the double curvature of square tile elements by means of a custom-designed digital fabrication set-up. The set-up consists of a standard 3D printer integrated with a bespoke numerically controlled actuator for textile pre-stretching. The first method couples a nonuniform pre-stretching of the textile and a uniform cross section of the 3D printed boundary. The second method involves the combination of a uniform pre-stretching and non-uniform cross-section across the tile boundary. We independently evaluate the two methods and compare them in terms of effectiveness and repeatability in the activation of the tile curvature, specifically focusing on the edge conditions of the fabricated tile components. Finally, we discuss the possibility for large-scale applications and the potential for further research.