Soft actuator with snap-through action

Soft actuators with snap-through action are a class of soft robotic devices that utilize snap-through instabilities to produce rapid and large-amplitude movements from minimal fluid input. These actuators typically consist of inflatable elastomeric segments that undergo sudden structural transitions between stable states, enabling fast shape changes, extension, gripping, or locomotion. The actuation speeds range from about 0.1 seconds for fluidic designs to as fast as 60 milliseconds for bistable fabric mechanisms, which can operate without continuous power by holding bistable states. These actuators are primarily research prototypes documented in peer-reviewed publications rather than commercial products. They are compatible with small compressors for portable use and can be customized for various motion modes. Their bistable operation reduces energy consumption by maintaining positions without continuous input, and some designs have demonstrated durability over a million cycles. However, they require precise fabrication of elastomeric instabilities and rely on pneumatic or fluidic inputs.