Enhanced Elastricstatic Layer Jamming for Variable Stiffness Using AC Excitation

Electrostatic layer jamming (ELJ) is a method toachieve variable stiffness in soft robotics. Traditional ELJ focuses on Direct Current(DC) voltages and ignores Alternating Current(AC) voltages. In this paper, by applying AC voltages of different frequencies to three ELJ devices (ELJ-AIR, ELJGERF, ELJ-OIL) based on different dielectric materials(air, giant electrorheological fluid, silicone oil), we discuss the effect of AC voltage and its frequency on the performance of ELJ devices. The experimental results show that the application of AC voltage can significantly improve the performance of ELJ devices. The stiffness of ELJ-AIR, ELJ-GERF and ELJ-OIL is increased by 4.4, 8.3 and 2.2 times, respectively. Moreover, AC voltage also significantly improves the electrostatic residual phenomenon and response speed of ELJ devices (by 7.7 times).