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Programming structures to realize any prescribed mechanical response under large deformation is highly desired for various functionalities, such as actuation and energy trapping. Yet, the use of a single material phase and heuristically developed structural patterns leads to restricted design space and potential failure to achieve specific target behaviors. Here, through a free-form inverse design approach, multiple hyperelastic materials with distinct properties are optimally synthesized into composite structures to precisely achieve arbitrary and extreme prescribed responses under large deformations. The digitally synthesized structures exhibit organic shapes and motions with irregular distributions of material phases. Within the structures, different materials play distinct roles yet seamlessly collaborate through sophisticated deformation mechanisms to produce the target behaviors, some of which are unachievable by a single material. While complex in geometry and material heterogeneity, the discovered structures are effectively manufactured via multimaterial fabrication with different polydimethylsiloxane (PDMS) elastomers with distinct behaviors and their highly nonlinear responses are physically and accurately realized in experiments. To enhance programmability, the synthesized structures are heteroassembled into architectures that exhibit highly complex yet navigable responses. The proposed synthesis, multimaterial fabrication, and heteroassembly strategy can be utilized to design function-oriented and situation-specific mechanical devices for a wide range of applications.
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This content will become publicly available on January 1, 2026
Prototyping high-fidelity multifunctional objects using single-nozzle multi-filament additive manufacturing system with active mixing
This paper aims to advance the field of additive manufacturing by producing multimaterial objects with intricate topological features and polylithic material distribution through an integrated approach. First, we develop a Single-Nozzle Multi-Filament (SNMF) system equipped with active mixing to blend multiple filaments and deposit a programmable mixture. The system can also deposit gradient transitions between different materials within a single print. Second, we establish a numerical model to represent the material transitional behavior and validated it with experiments. The model enables the precise control of the material transitional interface to ensure high material fidelity. Third, we propose three strategies for designing and modeling multimaterial objects catering to different application scenarios, including image sampling, 2D discrete patches, and 3D surface division. The system’s capabilities were validated through six case studies designed and fabricated through the above approaches for distinct application scenarios, demonstrating the successful materialization of complex designs with multiple functionalities.
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- Award ID(s):
- 1944691
- PAR ID:
- 10591622
- Publisher / Repository:
- Materials & Design
- Date Published:
- Journal Name:
- Materials & Design
- Volume:
- 249
- Issue:
- C
- ISSN:
- 0264-1275
- Page Range / eLocation ID:
- 113479
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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