Ultra-Sensitive & Fully-Soft Pneumatic Valve for High-Speed Oscillatory Applications

Recently, soft valves have been designed to enhance functionality in soft robots and achieve embodied control. However, most designs still use rigid components, need high control pressure to activate, and are not able to generate high-frequency oscillations. Here, we present a fully-soft valve, which can be triggered by kinking an elastomeric sleeve by using an inflatable origami pouch. The valve is compatible with high supply pressures and can interrupt a flow 100 times larger than its control signal. Afterwards, we use the valve to build fluidic oscillator circuits. These circuits exhibit high frequency oscillations which are tunable on the fly by sliding the valve actuator. We demonstrate the applicability of the circuit by driving a robot that swims at ≈ 0.5 BL.s<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup>. Furthermore, we demonstrate that multiple valves can be used to create amplification circuits, able to drive stiffer pneumatic actuators. Such circuits can amplify pressure signals by 10 folds, using only 2 valves.