Soft Robots Image
An electrochemical reaction-based transducer allows smooth control of fluidic systems in soft robots, enabling self-sensing actuation without complexity and opening doors to miniaturized soft robotic technology. (Credit: Shingo Maeda from SIT)

A fluid pump driven by electrochemical reactions is simple, lightweight, and silent, and it enables self-sensing actuation, with potential applications in wearable technology. The electrohydrodynamic (EHD) pumps uses an electrochemical dual transducer to sense the fluid flow, which, in turn, activates electrochemical reactions and increases current.

The team based the transducer design on an EHD pump they had previously designed. The pump consisted of a symmetrical arrangement of planar electrodes, which allowed an easy control of the flow direction by simply changing the voltage. Moreover, the arrangement enabled an obstruction-free flow and in the same amount in each direction owing to same strength of the electric field on either side.

The team evaluated sensing performance in terms of range of detectable flow, rate, sensitivity, response, and relaxation times. They used mathematical modeling to understand the sensing mechanism.