Flexible Valveless Pump for Bio Applications

Abstract

In electromechanical actuators Lorentz force law is used to convert electrical energy into rotational or linear mechanical energy. In these conventional electromechanical actuators, rigid wires conducts the electrical current and as such the types of motion generated by these actuators are limited. Recent advances in liquid metal alloys permit designing electrical wires that are stretchable. These flexible wires have been used to fabricate various flexible connections, sensors and antennas. However, there have been very little efforts to use these stretchable liquid metal wires as actuators. Building upon our previous work in this area, we have made a flexible pump which can be used in bio applications. In this design we placed a flexible polymeric substrate filled by liquid metal Galinstan between two permanent magnets. Since the pump should convey the biological cells suspended along the fluid flow, utilizing check valves may increase the risk of clog in the inlet or outlet. Therefore, our design is based on the nozzle/diffuser concept. This new pump can be considered as a peristaltic and valve-less mechanical pumps which utilizes the Lorentz force law as the actuating mechanism.

Lifetime of Liquid Metal Wires for Stretchable Devices

“…Wireless power transfer with Galinstan has been used for device charging ( J = 0.3 kAcm −2 , [ 34 ] J = 1–20 kAcm −2 [ 35 ] ) and wireless wearable devices. [ 36 ] Finally, silicone‐encapsulated Galinstan serves as the stretchable coil for electromagnetic actuators in soft robots, [ 37,38 ] pumps, [ 39 ] and loudspeakers, [ 40 ] with demonstrated current densities from 0.05 [ 37 ] to 10 kAcm −2 . [ 38 ]…”