pith. sign in

arxiv: 2606.07262 · v1 · pith:OFR5KHQBnew · submitted 2026-06-05 · ❄️ cond-mat.mtrl-sci · cond-mat.dis-nn

Towards Engineering Material Neural Networks

Pith reviewed 2026-06-27 21:34 UTC · model grok-4.3

classification ❄️ cond-mat.mtrl-sci cond-mat.dis-nn
keywords Engineering Material Neural NetworksPhysical Neural Networksadaptive materialsmetamaterialsliving materialstrainable parametersstructural intelligencearchitected materials
0
0 comments X

The pith

Structural configurations with interconnected adaptable nodes can approximate continuous functions by embedding trainable parameters into load-bearing materials.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper establishes that structural configurations with interconnected adaptable nodes are able to approximate continuous functions. This opens new possibilities beyond classical metamaterials and computational materials by allowing intelligence to be embedded directly into the structure through trainable physical parameters and neural network-inspired morphologies. The authors define the resulting systems as Engineering Material Neural Networks, or EMNNs, a subcategory of Physical Neural Networks. They outline the required mechanical and multifunctional properties and identify composites, architected materials, biological materials, and engineering living materials as promising candidates for realization.

Core claim

Structural configurations with interconnected adaptable nodes are able to approximate continuous functions, providing new possibilities and opportunities than classical metamaterials and computational materials. Load-bearing engineering materials can therefore be designed with trainable physical parameters and neural network-inspired morphologies, embedding intelligence directly into their structure as Engineering Material Neural Networks (EMNNs).

What carries the argument

Engineering Material Neural Networks (EMNNs): structural configurations with interconnected adaptable nodes whose local mechanical or multifunctional responses act as trainable parameters analogous to neural-network weights while preserving structural integrity.

If this is right

  • Adaptive material systems can operate without predefined designs or external electronics-based computing.
  • Reversibility, adaptive responses, and learning can be integrated directly into load-bearing structures.
  • Composites, architected materials, biological materials, and engineering living materials become candidates for trainable structural intelligence.
  • Future work in materials science and structural engineering can focus on developing EMNNs for engineering applications.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • Such networks could enable structures that adapt their mechanical behavior in response to changing loads without external intervention.
  • The approach may extend to problems in self-regulating infrastructure or autonomous robotic systems where computation and structure coincide.
  • A minimal test case would be a small lattice of adaptable nodes trained to map input displacements to desired output forces.

Load-bearing premise

Physical, load-bearing materials can be engineered so that their local mechanical or multifunctional responses function as trainable parameters analogous to neural-network weights while preserving structural integrity.

What would settle it

A demonstration that a physical structure of interconnected nodes can be adjusted at the local level to approximate a target continuous function under repeated mechanical loading without loss of load-bearing capacity.

Figures

Figures reproduced from arXiv: 2606.07262 by Adam W Perriman, Ali Momeni, Charles de Kergariou, Fabrizio Scarpa, Hortense Le Ferrand, Kunal Masania, Romain Fleury.

Figure 1
Figure 1. Figure 1: Neuromorphic structure and behaviour of an Engineering Material Neural Network. The yellow arrow at the back of the neural network represents the physical transformation of variable. Here the variable trans￾formed is ϕ and x is the space over which the physical variable is transformed. behavioural training and to reduce the time operators spend tuning physical parameters, enabling the structure to autonomo… view at source ↗
Figure 2
Figure 2. Figure 2: Theoretical concept, functions and operations of an EMNN during training and exploitation. a, Example of Artificial Neural Network (ANN) structure with interconnected nodes. b, Example of Engineering Material Neural Network (equivalent to the ANN) for temperature control. (λ: Thermal Conductivity; T: Temperature) c, Schematic presenting the information transmission in an EMNN. The clock symbols represent t… view at source ↗
Figure 3
Figure 3. Figure 3: Training strategies used and proposed for EMNNs. The techniques the further on the right present increased adaptability. The techniques at the lower rows present more physical training with less intervention of traditional computing and human intervention (ELM: Extreme Learning Machine; RC: Reservoir Computing). Full Physical Feedback Control is not a training technique but rather the objective for the tra… view at source ↗
Figure 4
Figure 4. Figure 4: Summary of research strategies highlighted in the present study to develop Engineering Mate￾rial Neural Networks (EMNNs). (ELM: Extreme Learning Machine ; RC: Reservoir Computing ; EMMUNN: Engineering Material Motor Unit Neural Network ; ϵ: Strain). The gear symbol highlights a potential for updating optimisation for the weight of the material or the design of material connectors. The hand symbols represen… view at source ↗
Figure 5
Figure 5. Figure 5: b do not intrinsically display permanent adaptability within the material, but can be used to generate EMMUNNs. Permanently non reversible adaptive materials of Fig. 5c can provide plat￾forms to design EMNNs with limited permanent adaptability, as only certain changes of properties are possible. Permanently reversible adaptive materials, presented in Fig. 5d are ideal candidates to for EMNNs, as they provi… view at source ↗
Figure 6
Figure 6. Figure 6: Two examples of EMNNs with different degrees of material physical adaptability for training. The Plane Aileron example presents how EMNNs can be used to integrate controllable and adaptable stiffness beams to automatically control the position of an aileron on a plane’s wing. The Grip Robot Hand example introduces how an EMNN can be created out of an assembly of magnet to control the roughness of a soft sk… view at source ↗
Figure 7
Figure 7. Figure 7: Subcategories of Engineering Material Neural Networks. The row labelled as Materials Properties presents the parameters of the materials to be modified in the training phase of the neural network-like structure (δ: displacement ;K: stiffness; κ: curvature; ϵ: displacement; T: Temperature; λ: thermal conductivity; σ: electrical conductivity; I:Electrical current intensity; χ: Magnetic field intensity; τ: op… view at source ↗
read the original abstract

Structures that capture functionality in the form of animate or intelligent machines have the potential to transform modern engineering applications. Animation and embedded intelligence are typically realised by integrating advanced capabilities such as reversibility, adaptive responses and learning directly into the materials themselves. Currently, the majority of adaptive material systems rely on predefined adaptive designs combined with in-service, electronics-based computing to dynamically modify the structural behaviour. However, structural configurations with interconnected adaptable nodes are able to approximate continuous functions, providing new possibilities and opportunities than classical metamaterials and computational materials. We discuss here the potential to design load-bearing engineering materials with trainable physical parameters and neural network-inspired morphologies, embedding intelligence directly into their structure, a concept we define as Engineering Material Neural Networks (EMNNs) as a subcategory of Physical Neural Networks. In this perspective, we first establish the foundational concept of EMNNs; we then detail the mechanical and multifunctional properties required for such structural configurations. Finally, we evaluate existing and emerging engineering materials that hold promise for enabling this innovative approach. Key material candidates for realising EMNNs include composites, architected, biological and engineering living materials. We also outline future directions in materials science and structural engineering for developing EMNNs.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

1 major / 1 minor

Summary. The manuscript is a perspective article introducing Engineering Material Neural Networks (EMNNs) as a subcategory of Physical Neural Networks. It defines EMNNs as load-bearing structural materials featuring interconnected adaptable nodes with trainable physical parameters and neural-network-inspired morphologies, capable of approximating continuous functions. The text outlines required mechanical and multifunctional properties, evaluates candidate material classes (composites, architected, biological, and living materials), and suggests future directions, while deferring feasibility demonstrations to subsequent work.

Significance. If the proposed analogy between material nodes and neural-network weights can be realized while preserving structural integrity, EMNNs could enable a new class of multifunctional materials that embed adaptive computation directly into load-bearing structures, extending beyond classical metamaterials. The categorization of EMNNs within Physical Neural Networks provides a clear conceptual framing that may help organize future research, though the manuscript itself contains no new derivations, data, or validated mappings.

major comments (1)
  1. [Abstract] Abstract: the statement that 'structural configurations with interconnected adaptable nodes are able to approximate continuous functions' is presented without citation, derivation, or even a brief sketch of the mapping from physical node responses to neural-network operations; this assertion is load-bearing for the entire proposal yet remains ungrounded within the manuscript.
minor comments (1)
  1. The sentence 'providing new possibilities and opportunities than classical metamaterials' is grammatically incomplete; rephrase for clarity (e.g., 'beyond those of classical metamaterials').

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for their thoughtful review and constructive comment on our perspective article. We address the major comment below and will incorporate revisions to strengthen the grounding of the central claim.

read point-by-point responses
  1. Referee: [Abstract] Abstract: the statement that 'structural configurations with interconnected adaptable nodes are able to approximate continuous functions' is presented without citation, derivation, or even a brief sketch of the mapping from physical node responses to neural-network operations; this assertion is load-bearing for the entire proposal yet remains ungrounded within the manuscript.

    Authors: We agree that the claim requires additional context to be properly grounded. Although the manuscript is a perspective that intentionally defers detailed feasibility studies and derivations to future work, we will revise the abstract and the opening of the introduction to include a concise sketch: interconnected adaptable nodes with trainable physical parameters can emulate the weighted summation and nonlinear activation steps of artificial neurons, thereby inheriting the universal approximation capability of neural networks when the physical responses are suitably mapped to network operations. We will also add citations to foundational works on physical neural networks and neuromorphic materials to support this framing. revision: yes

Circularity Check

0 steps flagged

No significant circularity; conceptual perspective with no derivations

full rationale

The manuscript is a perspective article that introduces the EMNNs concept by explicit definition as a subcategory of Physical Neural Networks and outlines required material properties plus candidate classes without any equations, proofs, fitted parameters, or predictions. No load-bearing steps reduce results to inputs by construction, self-citation, or ansatz; all claims remain forward-looking and defer feasibility to future work. The text contains no self-referential reductions of the enumerated kinds.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 1 invented entities

The central claim rests on the domain assumption that material architectures can physically realize neural-network-style function approximation; no free parameters, additional axioms, or invented physical entities are introduced beyond the conceptual definition of EMNNs.

axioms (1)
  • domain assumption Interconnected adaptable nodes in load-bearing materials can approximate continuous functions in a manner analogous to artificial neural networks.
    Invoked in the abstract as the basis for claiming new possibilities beyond classical metamaterials.
invented entities (1)
  • Engineering Material Neural Networks (EMNNs) no independent evidence
    purpose: To name and categorize load-bearing materials whose morphologies and trainable parameters embed neural-network functionality.
    Newly coined term without independent experimental support in the document.

pith-pipeline@v0.9.1-grok · 5763 in / 1206 out tokens · 23485 ms · 2026-06-27T21:34:50.360132+00:00 · methodology

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Reference graph

Works this paper leans on

122 extracted references

  1. [1]

    Accelerated data-driven materials science with the Materials Project,

    M. K. Horton, P. Huck, R. X. Yang, J. M. Munro, S. Dwaraknath, A. M. Ganose, R. S. Kingsbury, M. Wen, J. X. Shen, T. S. Mathis, A. D. Kaplan, K. Berket, J. Riebesell, J. George, A. S. Rosen, E. W. Spotte-Smith, M. J. McDermott, O. A. Cohen, A. Dunn, M. C. Kuner, G. M. Rignanese, G. Petretto, D. Waroquiers, S. M. Griffin, J. B. Neaton, D. C. Chrzan, M. Asta...

  2. [2]

    Signal Detection By Complex Spatial Filtering,

    A. Vander Lugt, “Signal Detection By Complex Spatial Filtering,” IEEE Transactions on Information Theory , vol. 10, no. 2, pp. 139–145, 1964

  3. [3]

    Training of physical neural networks,

    A. Momeni, B. Rahmani, B. Scellier, L. G. Wright, P. L. McMahon, C. C. Wanjura, Y. Li, A. Skalli, N. G. Berloff, T. Onodera, I. Oguz, F. Morichetti, P. del Hougne, M. Le Gallo, A. Sebastian, A. Mirhoseini, C. Zhang, D. Marković, D. Brunner, C. Moser, S. Gigan, F. Mar- quardt, A. Ozcan, J. Grollier, A. J. Liu, D. Psaltis, A. Alù, and R. Fleury, “Training o...

  4. [4]

    Training all-mechanical neural networks for task learning through in situ backpropagation,

    S. Li and X. Mao, “Training all-mechanical neural networks for task learning through in situ backpropagation,” Nat. Commun. , vol. 15, pp. 1–12, 12 2024

  5. [5]

    Mechanical computing,

    H. Yasuda, P. R. Buskohl, A. Gillman, T. D. Murphey, S. Stepney, R. A. Vaia, and J. R. Raney, “Mechanical computing,” Nat., vol. 598, pp. 39–48, 10 2021. 26

  6. [6]

    Reprogrammable and reconfigurable mechanical computing metastructures with stable and high-density memory,

    Y. Li, S. Yu, H. Qing, Y. Hong, Y. Zhao, F. Qi, H. Su, and J. Yin, “Reprogrammable and reconfigurable mechanical computing metastructures with stable and high-density memory,” Sci. Adv. , vol. 10, p. 6476, 6 2024

  7. [7]

    Mechanical Neural Networks with Explicit and Robust Neurons,

    T. Mei, Y. Zhou, and C. Q. Chen, “Mechanical Neural Networks with Explicit and Robust Neurons,” Adv. Sci. , vol. 11, 9 2024

  8. [8]

    In-memory mechanical computing,

    T. Mei and C. Q. Chen, “In-memory mechanical computing,” Nat. Commun., vol. 14, pp. 5204– , 8 2023

  9. [9]

    A mechanical metamaterial with reprogrammable logical functions,

    T. Mei, Z. Meng, K. Zhao, and C. Q. Chen, “A mechanical metamaterial with reprogrammable logical functions,” Nat. Commun. , vol. 12, pp. 1–11, 12 2021

  10. [10]

    Deep physical neural networks trained with backpropagation,

    L. G. Wright, T. Onodera, M. M. Stein, T. Wang, D. T. Schachter, Z. Hu, and P. L. McMahon, “Deep physical neural networks trained with backpropagation,” Nat., vol. 601, pp. 549–555, 1 2022

  11. [11]

    Advancing neuroengineering with Neuromorphic Twins,

    M. Chiappalone and T. Levi, “Advancing neuroengineering with Neuromorphic Twins,” Nat. Commun., vol. 17, pp. 1938–, 2 2026

  12. [12]

    Neuromorphic metamaterial structures,

    J. Sylvestre and J. F. Morissette, “Neuromorphic metamaterial structures,” Mater. Des. , vol. 210, p. 110078, 11 2021

  13. [13]

    Physical control: A new avenue to achieve intelligence in soft robotics,

    E. Milana, C. D. Santina, B. Gorissen, and P. Rothemund, “Physical control: A new avenue to achieve intelligence in soft robotics,” Sci. Robot., vol. 10, p. 7660, 5 2025

  14. [14]

    AUTOMATON ROVER FOR EXTREME ENVIRONMENTS NASA Inno- vative Advanced Concepts (NIAC) Phase I Final Report Principle Investigator,

    J. Sauder, E. Hilgemann, M. Johnson, A. Parness, B. Bienstock, J. H. Additional, J. Kawata, and K. Stack, “AUTOMATON ROVER FOR EXTREME ENVIRONMENTS NASA Inno- vative Advanced Concepts (NIAC) Phase I Final Report Principle Investigator,” tech. rep., 2017

  15. [15]

    Multilayer feedforward networks are universal approximators,

    K. Hornik, M. Stinchcombe, and H. White, “Multilayer feedforward networks are universal approximators,” Neural Netw. , vol. 2, no. 5, pp. 359–366, 1989

  16. [16]

    Metamaterial robotics,

    X. Zheng, Y. Jiang, M. Mete, J. Li, I. Watanabe, T. Yamada, and J. Paik, “Metamaterial robotics,” Sci. Robot., vol. 10, p. 1519, 11 2025

  17. [17]

    Shape-morphing metamaterials,

    K. K. Dudek, M. Kadic, C. Coulais, and K. Bertoldi, “Shape-morphing metamaterials,” Nat. Rev. Mater. , vol. 10, pp. 783–798, 7 2025. 27

  18. [18]

    A guidance to intelligent metamaterials and metamaterials intelligence,

    C. Qian, I. Kaminer, and H. Chen, “A guidance to intelligent metamaterials and metamaterials intelligence,” Nat. Commun. , vol. 16, pp. 1154–, 1 2025

  19. [19]

    Recent Advances of Auxetic Metamaterials in Smart Materials and Structural Systems,

    Y. Zhang, W. Z. Jiang, W. Jiang, X. Y. Zhang, J. Dong, Y. M. Xie, K. E. Evans, and X. Ren, “Recent Advances of Auxetic Metamaterials in Smart Materials and Structural Systems,” Adv. Funct. Mater., vol. 35, 6 2025

  20. [20]

    Mechanical metamaterials and beyond,

    P. Jiao, J. Mueller, J. R. Raney, X. R. Zheng, and A. H. Alavi, “Mechanical metamaterials and beyond,” Nat. Commun. , vol. 14, pp. 6004–, 9 2023

  21. [21]

    Supervised learning through physical changes in a mechanical system,

    M. Stern, C. Arinze, L. Perez, S. E. Palmer, and A. Murugan, “Supervised learning through physical changes in a mechanical system,” PNAS, vol. 117, pp. 14843–14850, 6 2020

  22. [22]

    Multimodal oscillator networks learn to solve a classification problem,

    D. de Bos and M. Serra-Garcia, “Multimodal oscillator networks learn to solve a classification problem,” npj Metamaterials , vol. 2, pp. 3–, 1 2026

  23. [23]

    Topological mechanical neural networks as classifiers through in situ backpropagation learning,

    S. Li and X. Mao, “Topological mechanical neural networks as classifiers through in situ backpropagation learning,” Mech. Syst. Signal Process. , vol. 250, p. 114198, 4 2026

  24. [24]

    Learning to self-fold at a bifurcation,

    C. Arinze, M. Stern, S. R. Nagel, and A. Murugan, “Learning to self-fold at a bifurcation,” Phys. Rev. E , vol. 107, p. 025001, 2 2023

  25. [25]

    Align, then memorise: the dynamics of learning with feedback alignment*,

    M. Refinetti, S. D’Ascoli, R. Ohana, and S. Goldt, “Align, then memorise: the dynamics of learning with feedback alignment*,” J. Phys. A: Math. Theor. , vol. 55, p. 044002, 1 2022

  26. [26]

    Limits of nonlinear and dispersive fiber propagation for an optical fiber-based extreme learning machine,

    A. V. Ermolaev, M. Hary, M. Hary, L. Leybov, P. Ryczkowski, A. Skalli, D. Brunner, G. Genty, J. M. Dudley, and J. M. Dudley, “Limits of nonlinear and dispersive fiber propagation for an optical fiber-based extreme learning machine,” Opt. Lett. , vol. 50, pp. 4166–4169, 7 2025

  27. [27]

    Recent advances in physical reservoir computing: A review,

    G. Tanaka, T. Yamane, J. B. Héroux, R. Nakane, N. Kanazawa, S. Takeda, H. Numata, D. Nakano, and A. Hirose, “Recent advances in physical reservoir computing: A review,” Neural Netw. , vol. 115, pp. 100–123, 7 2019

  28. [28]

    Principles and metrics of extreme learning machines using a highly nonlinear fiber,

    M. Hary, D. Brunner, L. Leybov, P. Ryczkowski, J. M. Dudley, and G. Genty, “Principles and metrics of extreme learning machines using a highly nonlinear fiber,” Nanophotonics, vol. 14, pp. 2733–2748, 8 2025

  29. [29]

    Multiplexed gradient descent: Fast online training of modern datasets on hardware neural networks without backpropagation,

    A. N. McCaughan, B. G. Oripov, N. Ganesh, S. W. Nam, A. Dienstfrey, and S. M. Buckley, “Multiplexed gradient descent: Fast online training of modern datasets on hardware neural networks without backpropagation,” APL mach. learn. , vol. 1, p. 26118, 6 2023. 28

  30. [30]

    Training Neural Networks with Local Error Signals,

    A. Nøkland and L. H. Eidnes, “Training Neural Networks with Local Error Signals,” Proceed- ings of Machine Learning Research , vol. 97, pp. 4839–4850, 5 2019

  31. [31]

    Self-Learning Machines Based on Hamiltonian Echo Backpropagation,

    V. López-Pastor and F. Marquardt, “Self-Learning Machines Based on Hamiltonian Echo Backpropagation,” Phys. Rev. X , vol. 13, p. 031020, 8 2023

  32. [32]

    Physical learning in reprogrammable metamaterials for adaptation to unknown environments,

    K. J. Chen, C. Catrambone, C. Sowinski, J. Mukobi, E. Andreacchio, E. Chew, A. Mor- land, and M. Sakovsky, “Physical learning in reprogrammable metamaterials for adaptation to unknown environments,” arXiv, 10 2025

  33. [33]

    Mechanical neural networks: Architected materials that learn behaviors,

    R. H. Lee, E. A. B. Mulder, and J. B. Hopkins, “Mechanical neural networks: Architected materials that learn behaviors,” Sci. Robot., vol. 7, 10 2022

  34. [34]

    Using binary-stiffness beams within mechanical neural-network metamaterials to learn,

    J. B. Hopkins, R. H. Lee, and P. Sainaghi, “Using binary-stiffness beams within mechanical neural-network metamaterials to learn,” Smart Mater. Struct. , vol. 32, p. 035015, 2 2023

  35. [35]

    Intelligent mechanical metamaterials towards learning static and dynamic behaviors,

    J. Chen, X. Miao, H. Ma, J. B. Hopkins, and G. Huang, “Intelligent mechanical metamaterials towards learning static and dynamic behaviors,” Mater. Des. , vol. 244, p. 113093, 8 2024

  36. [36]

    Mechanical Neural Network: Making AI Comprehensible for Everyone,

    A. Schaffland and J. Schoning, “Mechanical Neural Network: Making AI Comprehensible for Everyone,” 2023 IEEE 2nd German Education Conference, GECon 2023 , 2023

  37. [37]

    Metamaterials that learn to change shape,

    Y. Du, R. van Mastrigt, J. Veenstra, and C. Coulais, “Metamaterials that learn to change shape,” Nat. Phys. , pp. 1–7, 4 2026

  38. [38]

    Experimental demonstration of coupled learning in elastic networks,

    L. E. Altman, M. Stern, A. J. Liu, and D. J. Durian, “Experimental demonstration of coupled learning in elastic networks,” Phys. Rev. Appl. , vol. 22, p. 024053, 8 2024

  39. [39]

    Controlled Mechanical Anisotropy in 3D-Printed Thermoplastic Elastomeric Composites,

    N. A. Patil, W. Wang, J. Lee, D. KadiyalaBhavani, A. Amirkhizi, T. J. Lawton, E. D. Wetzel, and J. H. Park, “Controlled Mechanical Anisotropy in 3D-Printed Thermoplastic Elastomeric Composites,” Macromol. Mater. Eng. , p. e00285, 2025

  40. [40]

    Desynchronous learning in a physics-driven learning network,

    J. F. Wycoff, S. Dillavou, M. Stern, A. J. Liu, and D. J. Durian, “Desynchronous learning in a physics-driven learning network,” J. Chem. Phys. , vol. 156, p. 144903, 4 2022

  41. [41]

    Supervised Learning in Physical Networks: From Machine Learning to Learning Machines,

    M. Stern, D. Hexner, J. W. Rocks, and A. J. Liu, “Supervised Learning in Physical Networks: From Machine Learning to Learning Machines,” Phys. Rev. X , vol. 11, p. 021045, 5 2021

  42. [42]

    Contrastive Hebbian Learning in the Continuous Hopfield Model,

    J. R. Movellan, “Contrastive Hebbian Learning in the Continuous Hopfield Model,” Connec- tionist Models , vol. 1, pp. 10–17, 1 1991. 29

  43. [43]

    Spatially programmable origami networks enable high- density mechanical computing for autonomous robotics,

    X. Hu, T. Tan, Y. Chen, and Z. Yan, “Spatially programmable origami networks enable high- density mechanical computing for autonomous robotics,” Nat. Commun. , vol. 16, pp. 10209–, 11 2025

  44. [44]

    Motor Unit,

    C. Heckman and R. M. Enoka, “Motor Unit,” Compr. Physiol., vol. 2, pp. 2629–2682, 10 2012

  45. [45]

    Design and fabrication of a three-dimensional meso-sized robotic metamaterial with actively controlled properties,

    C. Luo, Y. Song, C. Zhao, S. Thirumalai, I. Ladner, M. A. Cullinan, and J. B. Hopkins, “Design and fabrication of a three-dimensional meso-sized robotic metamaterial with actively controlled properties,” Mater. Horiz. , vol. 7, pp. 229–235, 1 2020

  46. [46]

    Phase-Changing Metamaterial Capable of Variable Stiffness and Shape Morphing,

    R. Poon and J. B. Hopkins, “Phase-Changing Metamaterial Capable of Variable Stiffness and Shape Morphing,” Adv. Eng. Mater. , vol. 21, p. 1900802, 12 2019

  47. [47]

    Physical neural network; Physics-Aware Back-Propagation; Shading facade; 4D printing; Biocomposites,

    C. de Kergariou, D. Correa, A. Perriman, H. Hauser, and F. Scarpa, “Physical neural network; Physics-Aware Back-Propagation; Shading facade; 4D printing; Biocomposites,” Advanced Science (Under Review) , 2026

  48. [48]

    Viewpoint: From Responsive to Adaptive and Interactive Materials and Mate- rials Systems: A Roadmap,

    A. Walther, “Viewpoint: From Responsive to Adaptive and Interactive Materials and Mate- rials Systems: A Roadmap,” Adv. Mater. , vol. 32, 5 2020

  49. [49]

    Physical deep learning with biologically inspired training method: gradient-free approach for physical hardware,

    M. Nakajima, K. Inoue, K. Tanaka, Y. Kuniyoshi, T. Hashimoto, and K. Nakajima, “Physical deep learning with biologically inspired training method: gradient-free approach for physical hardware,” Nat. Commun. , vol. 13, pp. 7847–, 12 2022

  50. [50]

    New insights into thermal conductivity of uniaxially stretched high density polyethylene films,

    R. C. Zhang, Z. Huang, D. Sun, D. Ji, M. Zhong, D. Zang, J. Z. Xu, Y. Wan, and A. Lu, “New insights into thermal conductivity of uniaxially stretched high density polyethylene films,” Polymer, vol. 154, pp. 42–47, 10 2018

  51. [51]

    Strain-Tunable Thermal Conductivity in Largely Amorphous Polyolefin Fibers via Alignment-Induced Vibra- tional Delocalization,

    D. Xu, B. Li, Y. Lyu, V. J. Santamaria-Garcia, Y. Zhu, and S. V. Boriskina, “Strain-Tunable Thermal Conductivity in Largely Amorphous Polyolefin Fibers via Alignment-Induced Vibra- tional Delocalization,” MIT News , 2 2026

  52. [52]

    Enhanced Electrical Conductivity and Seebeck Coefficient in PEDOT:PSS via a Two-Step Ionic liquid and NaBH4 Treatment for Organic Thermoelectrics,

    J. Atoyo, M. R. Burton, J. McGettrick, and M. J. Carnie, “Enhanced Electrical Conductivity and Seebeck Coefficient in PEDOT:PSS via a Two-Step Ionic liquid and NaBH4 Treatment for Organic Thermoelectrics,” Polymers 2020, Vol. 12, , vol. 12, 3 2020

  53. [53]

    Water-induced finger wrinkles improve handling of wet objects,

    K. Kareklas, D. Nettle, and T. V. Smulders, “Water-induced finger wrinkles improve handling of wet objects,” Biol. Lett. , vol. 9, 4 2013. 30

  54. [54]

    Self-learning mechanical circuits,

    V. P. Patil, I. Ho, and M. Prakash, “Self-learning mechanical circuits,” arXiv, 4 2023

  55. [55]

    A consistent method to design and evaluate the performance of Anti-Roll Tanks for ships,

    G. Kapsenberg and N. Carette, “A consistent method to design and evaluate the performance of Anti-Roll Tanks for ships,” Sh. Technol. Res. , vol. 70, pp. 117–145, 5 2023

  56. [56]

    Rotary 4D Printing of Programmable Metamaterials on Sustainable 4D Mandrel,

    H. Soleimanzadeh, M. Bodaghi, M. Jamalabadi, B. Rolfe, and A. Zolfagharian, “Rotary 4D Printing of Programmable Metamaterials on Sustainable 4D Mandrel,” Adv. Mater. Technol., 9 2025

  57. [57]

    Effect of pH and salt on the stiffness of polyelectrolyte multilayer microcapsules,

    V. V. Lulevich and O. I. Vinogradova, “Effect of pH and salt on the stiffness of polyelectrolyte multilayer microcapsules,” Langmuir, vol. 20, pp. 2874–2878, 3 2004

  58. [58]

    Reprogrammable Dual-Regulated Pollen Actuators for Geometric Encoding,

    J. Deng, Z. Zhao, A. Ahmad, J. Li, Y. H. Choe, Y. C. Lin, S. I. Mohammed, C. Zhou, and N. J. Cho, “Reprogrammable Dual-Regulated Pollen Actuators for Geometric Encoding,” Adv. Mater., vol. 38, p. e15030, 2 2025

  59. [59]

    High stiffness polymer composite with tunable transparency,

    P. S. Owuor, V. Chaudhary, C. F. Woellner, V. Sharma, R. V. Ramanujan, A. S. Stender, M. Soto, S. Ozden, E. V. Barrera, R. Vajtai, D. S. Galvão, J. Lou, C. S. Tiwary, and P. M. Ajayan, “High stiffness polymer composite with tunable transparency,” Mater. Today, vol. 21, pp. 475–482, 6 2018

  60. [60]

    The influence of the humidity on the mechanical properties of 3D printed continuous flax fibre reinforced poly(lactic acid) composites,

    C. de Kergariou, H. Saidani-Scott, A. Perriman, F. Scarpa, and A. Le Duigou, “The influence of the humidity on the mechanical properties of 3D printed continuous flax fibre reinforced poly(lactic acid) composites,” Compos. Part A Appl. Sci. Manuf. , vol. 155, pp. 1–12, 4 2022

  61. [61]

    Damage in biocomposites: Stiffness evolution of aligned plant fibre composites during monotonic and cyclic fatigue loading,

    D. U. Shah, “Damage in biocomposites: Stiffness evolution of aligned plant fibre composites during monotonic and cyclic fatigue loading,” Comp. Part A: Appl. Sci. Manuf. , vol. 83, pp. 160–168, 4 2016

  62. [62]

    Mechanical properties of spider dragline silk: Humidity, hysteresis, and relaxation,

    T. Vehoff, A. Glišović, H. Schollmeyer, A. Zippelius, and T. Salditt, “Mechanical properties of spider dragline silk: Humidity, hysteresis, and relaxation,” Biophys. J., vol. 93, pp. 4425–4432, 12 2007

  63. [63]

    Shear modulus and dilatancy softening in granular packings above jamming,

    C. Coulais, A. Seguin, and O. Dauchot, “Shear modulus and dilatancy softening in granular packings above jamming,” Phys. Rev. Lett. , vol. 113, p. 198001, 11 2014

  64. [64]

    Rate dependence in granular matter with application to tunable metamaterials,

    M. Liu, W. Mao, Y. Zhao, Q. Xu, Y. Gan, Y. Wang, and K. J. Hsia, “Rate dependence in granular matter with application to tunable metamaterials,” Matter, vol. 98, p. 102562, 12 2025. 31

  65. [65]

    Vibration characteristics of electrorheological elastomer sandwich beams,

    K. Wei, Q. Bai, G. Meng, and L. Ye, “Vibration characteristics of electrorheological elastomer sandwich beams,” Smart Mater. Struct. , vol. 20, p. 055012, 4 2011

  66. [66]

    Bio-inspired mechanically adaptive materials through vibration-induced crosslinking,

    Z. Wang, J. Wang, J. Ayarza, T. Steeves, Z. Hu, S. Manna, and A. P. Esser‐Kahn, “Bio-inspired mechanically adaptive materials through vibration-induced crosslinking,” Nat. Mater., vol. 20, pp. 869–874, 2 2021

  67. [67]

    Ultra-programmable buckling- driven soft cellular mechanisms,

    S. Janbaz, F. S. Bobbert, M. J. Mirzaali, and A. A. Zadpoor, “Ultra-programmable buckling- driven soft cellular mechanisms,” Mater. Horiz. , vol. 6, pp. 1138–1147, 7 2019

  68. [68]

    Monolithic binary stiffness building blocks for mechanical digital machines,

    P. R. Kuppens, M. A. Bessa, J. L. Herder, and J. B. Hopkins, “Monolithic binary stiffness building blocks for mechanical digital machines,” Extreme Mech. Lett. , vol. 42, p. 101120, 1 2021

  69. [69]

    Self-deployable contracting-cord metamaterials with tunable mechanical properties,

    W. Yan, T. Jones, C. L. Jawetz, R. H. Lee, J. B. Hopkins, and A. Mehta, “Self-deployable contracting-cord metamaterials with tunable mechanical properties,” Mater. Horiz. , vol. 11, pp. 3805–3818, 8 2024

  70. [70]

    Light-, pH- and thermal-responsive hydrogels with the triple-shape memory effect,

    Y. Y. Xiao, X. L. Gong, Y. Kang, Z. C. Jiang, S. Zhang, and B. J. Li, “Light-, pH- and thermal-responsive hydrogels with the triple-shape memory effect,” Chem. Commun. , vol. 52, pp. 10609–10612, 8 2016

  71. [71]

    Hybrid 4D printing of flexible multi- functional composites by multi jet fusion and direct ink writing,

    M. Chen, R. An, F. Demoly, H. J. Qi, and K. Zhou, “Hybrid 4D printing of flexible multi- functional composites by multi jet fusion and direct ink writing,” Mater. Sci. Eng. R: Rep. , vol. 163, p. 100890, 4 2025

  72. [72]

    Design of 3D and 4D printed continuous fibre composites via an evolutionary algorithm and voxel- based Finite Elements: Application to natural fibre hygromorphs,

    C. de Kergariou, B. C. Kim, A. Perriman, A. Le Duigou, S. Guessasma, and F. Scarpa, “Design of 3D and 4D printed continuous fibre composites via an evolutionary algorithm and voxel- based Finite Elements: Application to natural fibre hygromorphs,” Addit. Manuf. , vol. 59, p. 103144, 11 2022

  73. [73]

    Development of an electro- thermo-mechanical 4D printed multi-shape smart actuator: Experiments and simulation,

    R. Delbart, C. Robert, T. Q. T. Hoang, and F. Martinez-Hergueta, “Development of an electro- thermo-mechanical 4D printed multi-shape smart actuator: Experiments and simulation,” Compos. - A: Appl. Sci. Manuf. , p. 108381, 7 2024

  74. [74]

    Hy- gromnemics: Programmable Material Memory Matter Actuators via Wet Pre‐Constraining,

    C. de Kergariou, F. S. G. Smith, R. S. Trask, A. W. Perriman, F. Scarpa, and D. Correa, “Hy- gromnemics: Programmable Material Memory Matter Actuators via Wet Pre‐Constraining,” Adv. Mater. Technol. , 8 2025. 32

  75. [75]

    On the Influence of Humidity on a Thermal Conductivity Sensor for the Detection of Hydrogen,

    S. Emperhoff, M. Eberl, T. Dwertmann, and J. Wöllenstein, “On the Influence of Humidity on a Thermal Conductivity Sensor for the Detection of Hydrogen,” Sensors, vol. 24, 4 2024

  76. [76]

    Strain effects on the thermal conductivity of nanostructures,

    X. Li, K. Maute, M. L. Dunn, and R. Yang, “Strain effects on the thermal conductivity of nanostructures,” Phys. Rev. B , vol. 81, p. 245318, 6 2010

  77. [77]

    Light-triggered thermal conductivity switching in azobenzene polymers,

    J. Shin, J. Sung, M. Kang, X. Xie, B. Lee, K. M. Lee, T. J. White, C. Leal, N. R. Sottos, P. V. Braun, and D. G. Cahill, “Light-triggered thermal conductivity switching in azobenzene polymers,” Proceedings of the National Academy of Sciences of the United States of America , vol. 116, pp. 5973–5978, 3 2019

  78. [78]

    Orientation behavior and thermal conductivity of liquid crystal polymer composites based on Three-Dimensional printing,

    F. Luo, S. Yang, P. Yan, H. Li, B. Huang, Q. Qian, and Q. Chen, “Orientation behavior and thermal conductivity of liquid crystal polymer composites based on Three-Dimensional printing,” Compos. - A: Appl. Sci. Manuf. , vol. 160, p. 107059, 9 2022

  79. [79]

    Segregated and Non-Settling Liquid Metal Elastomer via Jamming of Elastomeric Particles,

    X. Xue, D. Zhang, Y. Wu, R. Xing, H. Li, T. Yu, B. Bai, Y. Tao, M. D. Dickey, and J. Yang, “Segregated and Non-Settling Liquid Metal Elastomer via Jamming of Elastomeric Particles,” Adv. Funct. Mater. , vol. 33, p. 2210553, 2 2023

  80. [80]

    Effect of visible light on the elec- trical conductivity of conductive grade PEDOT:PSS,

    S. Yigzaw, N. Bekri, A. Gedifew, S. Alayau, and A. Benor, “Effect of visible light on the elec- trical conductivity of conductive grade PEDOT:PSS,” Mater. Res. Express, vol. 12, p. 086302, 8 2025

Showing first 80 references.