BiEOP: A Bistable, Soft Actuator Driven by Electroosmotic Pumps
Tianyu Yu, Hajun Lee, Lining Yao. IEEE RoboSoft 2026. PDF
🏆 Best Student Paper Award
🏅 Young Research Paper Finalist
🏅 ZooQuarium (Demo) Finalist
Bistable actuators have provided unique advantages for soft robotics, such as reconfigurable shape or multifunctional behaviors. However, achieving self-contained and controllable bistable actuation still remains challenging. In this work, we present BiEOP, a bistable soft actuator driven by electroosmotic pumps (EOPs). BiEOP consists of two symmetric, dome-shaped elastic shells separated by an EOP layer, which transfers internal working liquid under electrical actuation below 300 V to switch between the actuator’s bistable configurations. We analyze and experimentally validate its bistable behavior based on the pressure–volume characterization of the elastic shell. We then demonstrate a soft robot composed of multiple BiEOP modules that reconfigures its body shape to switch between bristle locomotion and surface adhesion functions. This reconfigurability enables diverse functional behaviors, such as remaining stationary in windy environments or picking up and transporting flake samples for pipe inspection. We envision BiEOP as a modular actuator capable of inducing shape reconfiguration and multifunctionality in the design of future soft robots.
