TEXTILES.ORG
Most fluid-based wearable technologies require a large, inconvenient pump that is difficult to incorporate into clothing. Researchers at the Swiss Federal Institute of Technology in Lausanne, Switzerland, have developed a solution: flexible, fiber-like pumps that can be woven or sewn into textiles.
The pumps use charge injection electrohydrodynamics (EHD) to generate fluid flow without any moving parts. The two helical electrodes embedded in the pump wall ionize, accelerating molecules of a nonconductive liquid. The ion movement and electrode shape create a forward fluid flow that is silent and vibration-free and requires only a small battery and power supply.
The structure of the pumps is created by twisting copper wires and polyurethane threads together around a steel rod and then fusing them with heat. Once the rod is removed, the 2-millimeter (0.08-inch) fibers can be integrated into textiles using standard weaving and sewing methods.
With the necessary materials being cheap and readily available, these flexible pumps offer a welcome alternative to their clunky, noisy counterparts.
Additionally, because the amount of pressure generated by the pump is directly linked to its length, the tubes can easily be cut for use in any application. They can also be washed with traditional detergents.
The pumps have the potential to apply to several circumstances, such as circulating hot and cold liquids through garments for those in environments with extreme temperatures or powering the artificial muscles of soft exoskeletons to help patients move and walk.
The research was published in the journal Science in March 2023.