Lower‐Voltage‐Driven Deformable Soft Electrothermal Actuators with Embedded Liquid Metal EGaIn

Abstract

In recent years, soft electrothermal actuators (ETAs) with low voltage drives have been applied in the field of human‐machine interface (iHMI) because of their safety and low power consumption. However, great challenges remain for achieving high‐performance, low‐cost and low‐voltage ETAs manufacturing. Herein, an ETA embedded with a conductive circuit fabricated using the liquid metal of eutectic gallium‐indium alloy (EGaIn), was developed using the 3D printing technology. Resistance stability, transmittance (92.1%), and heat generation capacity (246 °C at 1.484 V) of the ETAs were investigated to evaluate its performance. when the thickness ratio is 10:1, and the length‐width is 8:1, the ETA with U‐shaped conductive circuit structures shows higher bending performance. Three different categories of deformative structures (S‐shaped, flower‐shaped, and bridge‐shaped) were designed via planning the PI position of ETAs to investigate the deformation possibility of multiple structural deformations of ETA. Finally, a flexible smart gripper consisting of five ETAs was developed to demonstrate its potential application. Our study demonstrates that the developed ETA has high heat production capacity, high resistance stability and excellent bending performance at low voltage drives.