Towards gradient multimaterial toolpath generation for direct ink writing with connected fermat spirals

Sage, M. R. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Telles, R. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Galvan, H. R. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Dudukovic, N. A. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Gongora, A. E. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Cook, C. C. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Vuppuluri, V. S. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Golobic, A. M. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Walton, B. L. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]; Nguyen, D. T. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]

doi:10.1016/j.addma.2026.105214

DOE OSTI · 3376078

Towards gradient multimaterial toolpath generation for direct ink writing with connected fermat spirals

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Abstract

This work describes advances towards a reproducible, parametrically defined algorithm for generating graded multimaterial toolpaths for direct ink writing. Expanding on the existing Fermat space-filling algorithm and coupling with image-driven processing techniques, we demonstrate the fabrication of multimaterial structures. Here, material composition is encoded within toolpaths by parsing hue values from a multi-colored image. By performing dynamic velocity compensation based on local curvature and Euclidean distance filtering, internal voids are mitigated while optimizing print fidelity. Here, the work opens new avenues for designing complex toolpaths with locally programmable composition.

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3D Printing Contour-Parallel Spiral Direct Ink Writing Multimaterial Toolpath

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Sage, M. R. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Telles, R. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Galvan, H. R. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Dudukovic, N. A. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Gongora, A. E. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Cook, C. C. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Vuppuluri, V. S. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Golobic, A. M. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Walton, B. L. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)], Nguyen, D. T. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]. 2026-05-05. Towards gradient multimaterial toolpath generation for direct ink writing with connected fermat spirals. https://doi.org/10.1016/j.addma.2026.105214

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