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Clay 3D printing provides the benefits of digital fabrication automation and reconfigurability through a method that evokes manual clay coiling. Existing design technologies for clay 3D printing reflect the general 3D printing workflow in which solid forms are designed in CAD and then converted into a toolpath. In contrast, in hand-coiling, form is determined by the actions taken by the artist’s hands through space in response to the material. We theorized that an action-oriented approach for clay 3D printing could allow creators to design digital fabrication toolpaths that reflect clay material properties. We present CoilCAM, a domain-specific CAM programming system that supports the integrated generation of parametric forms and surface textures through mathematically defined toolpath operations. We developed CoilCAM in collaboration with ceramics professionals and evaluated CoilCAM’s relevance to manual ceramics by reinterpreting hand-made ceramic vessels. This process revealed the importance of iterative variation and embodied experience in action-oriented workflows.
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This content will become publicly available on February 1, 2026
Automated toolpath design of 3D concrete printing structural components
3D concrete printing (3DCP) structural components for construction assemblies are known for reduced material use and enhanced efficiency and design freedom. This article investigates the limitations in the geometrical and toolpath design of 3DCP structural components and presents an automated and comprehensive approach to their toolpath design and optimization. It exploits hierarchical geometric data structures and graph algorithms to achieve the following features: (1) By analyzing the overhang of toolpaths, the method offers quantitative criteria for determining the buildability of the components and predicting failure, thus assisting design decisions. (2) It provides toolpath offsetting and filleting methods that can enhance the dimensional accuracy of the print concerning layer line textures and overfills. (3) For branching and porous geometries, the method creates as-continuous-as-possible toolpaths with minimal stop-starts based on their topologies, thus reducing seam defects. (4) It converts the toolpath into efficient visualization meshes representing layer line textures and toolpath meshes compatible with finite elements analysis. The proposed method is implemented as a plug-in software within the environment of Grasshopper® for Rhino® to facilitate designers and engineers working with 3DCP. The effectiveness and versatility of the tool are demonstrated through the toolpath design and printing of four sets of examples. The tool reduces the number of toolpaths by 90% for a typical 80 mm nozzle and takes 0.21 s per meter of toolpath to slice, analyze overhang, generate continuous printing toolpaths, and visualize the print.
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- Award ID(s):
- 2037097
- PAR ID:
- 10591620
- Publisher / Repository:
- Additive Manufacturing
- Date Published:
- Journal Name:
- Additive Manufacturing
- Volume:
- 100
- Issue:
- C
- ISSN:
- 2214-8604
- Page Range / eLocation ID:
- 104662
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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