GrowCAD: bioinspired mathematical design for additive manufacturing.

Abstract

While the socioeconomic and environmental benefits of additive manufacturing (AM) are acknowledged, design for AM remains a perpetual challenge in the wider implementation of the technique. Design in the context of AM is an interconnected and broad topic. It encompasses not only function and form, but also how geometry is represented digitally, the associated software and human problem-solving capabilities within the geometric opportunities and constraints. This research focuses on enhancing human knowledge and creativity within the bounds of an ever-evolving design space, encompassing digital and human capabilities. A bioinspired methodology is introduced, drawing an analogy between plant growth and the layer-by-layer AM process. This results in the development of a novel length-polar-projection coordinate system, and the associated algebraic definition of centre lines and cross-sections. This mathematical representation of geometry forms the foundation of the design framework, GrowCAD^TM. Retaining the algebraic format of the geometry enables a manufacturability analysis, parametric editability and computer-aided design compatibility. The research is validated through qualitative analysis of the shape fidelity and efficiency, the ability to detect non-manufacturable geometry, the end-to-end functionality and the printability of the successful geometries. The simplicity and intuitive nature of GrowCAD^TM offer a method by which to enhance the engineer's knowledge and creativity.