Articles | Volume 16, issue 2
https://doi.org/10.5194/ms-16-831-2025
https://doi.org/10.5194/ms-16-831-2025
Research article
 | 
18 Nov 2025
Research article |  | 18 Nov 2025

A straw-inspired statically balanced compliant torque coupling

Xiaochen Yang, Jiayao Ma, and Yan Chen

Cited articles

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Bende, N. P., Yu, T., Corbin, N. A., Dias, M. A., Santangelo, C. D., Hanna, J. A., and Hayward, R. C.: Overcurvature induced multistability of linked conical frusta: how a “bendy straw” holds its shape, Soft Matter, 14, 8636–8642, https://doi.org/10.1039/C8SM01355A, 2018. 
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Short summary
Inspired by the azimuthal stability of bent straws, we designed a statically balanced compliant torque coupling to achieve near-perfect efficiency. Numerical and analytical modelling revealed bending stability and enabled programmable design. Scanning results corroborated simulations, demonstrating periodic deformation and conserved strain energy in materials during torsion. Testing confirmed that 98° torque transmission achieves over 75 % efficiency, surpassing conventional flexible couplings.
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