Skin-like micropumps transform human motion into fluidic flow via morphing valves

Area of Science:

• Biomedical Engineering
• Materials Science
• Fluid Dynamics

Background:

• Wearable healthcare requires portable, integrated fluidic systems.
• Existing micropumps often rely on rigid hardware, limiting portability and on-body use.

Purpose of the Study:

• To introduce OSMiPump, a novel power-free, strain-driven micropump.
• To demonstrate its capability for unidirectional fluid transport using human motion.
• To establish its potential for next-generation wearable biomedical systems.

Main Methods:

• Designed a soft, monolithic micropump integrating out-of-surface microchannels (OSMiCs) and self-actuated valves (OSMiValves).
• Utilized computational fluid-structure interaction modeling and nonlinear shell deformation analysis.
• Experimentally validated performance across various parameters including strain, fluid viscosity, and resistance.

Main Results:

• OSMiPump converts cyclic tensile strain into unidirectional fluid flow via valve snap-through/snap-back.
• Achieved flow rates up to ~0.16 µL/s and peak pressures of ~11 kPa.
• Demonstrated consistent operation over 100 cycles with tunable pumping behavior.

Conclusions:

• OSMiPump is a soft, skin-conformal micropump actuated by natural human motion.
• Its monolithic architecture and self-actuating valves enable portable, power-free fluid transport.
• The technology is versatile for applications like wound care and drug delivery in wearable systems.