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arXiv · 2602.18421

Snapping Actuators with Asymmetric and Sequenced Motion

Xin Li·Ye Jin·Mohsen Jafarpour·Hugo de Souza Oliveira·Edoardo Milana
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Abstract

Snapping instabilities in soft structures offer a powerful pathway to achieve rapid and energy-efficient actuation. In this study, an eccentric dome-shaped snapping actuator is developed to generate controllable asymmetric motion through geometry-induced instability. Finite element simulations and experiments reveal consistent asymmetric deformation and the corresponding pressure characteristics. By coupling four snapping actuators in a pneumatic network, a compact quadrupedal robot achieves coordinated wavelike locomotion using only a single pressure input. The robot exhibits frequency-dependent performance with a maximum speed of 72.78~mm/s at 7.5~Hz. These findings demonstrate the potential of asymmetric snapping mechanisms for physically controlled actuation and lay the groundwork for fully untethered and efficient soft robotic systems.

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Xin Li, Ye Jin, Mohsen Jafarpour, Hugo de Souza Oliveira, Edoardo Milana. 2026-02-20. Snapping Actuators with Asymmetric and Sequenced Motion. https://arxiv.org/abs/2602.18421

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