Snapping Actuators with Asymmetric and Sequenced Motion

TL;DR

This paper introduces an eccentric dome-shaped snapping actuator that produces controllable asymmetric motion, enabling a soft quadrupedal robot to achieve coordinated wavelike locomotion with a single pressure input, demonstrating efficient and rapid actuation.

Contribution

It presents a novel eccentric dome-shaped snapping actuator and demonstrates its application in a soft robot for coordinated locomotion using asymmetric snapping mechanisms.

Findings

Maximum speed of 72.78 mm/s at 7.5 Hz

Consistent asymmetric deformation observed in simulations and experiments

Single pressure input can control complex locomotion

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.