Locally addressable pneumatic actuation with embedded soft valves

This paper describes a method to fabricate pneumatic network (pneu-net)-based actuators with embedded soft valves that can be readily integrated for the local control of motions. Soft actuators consisting of pneu-nets of elastomeric chambers have been widely developed, while locally addressable control of motion remains challenging. Integration of valves is beneficial to achieve such controls, although existing methods rely on rigid components that would compromise the local flexibility of the actuators. To address this problem, we designed pneumatic soft valves consisting of elastomeric chambers, microchannels, and a straining layer to realize fully elastomeric actuators. Integration of the soft valves with typical pneu-net actuators was demonstrated via a simple molding process using 3D-printed templates. The embedded soft valves allowed regulating the airflow to the pneu-net to control the mode of actuation without causing undesired deformation. Using the developed principle, we demonstrated two representative devices—soft valve-embedded pneu-net actuators and selectively actuatable pneu-net pads—to showcase multiple modes of deformation based on locally controllable actuation. This is the first report of the fully elastomeric pneu-net actuators whose motions can be controlled by local deformation with the pneumatically controlled soft valves. The concept developed here—integrating fully elastomeric valves into pneu-nets—will contribute to design the motions of soft actuators only with pneumatic input without relying on rigid electronic and mechanical components.