A Low Voltage-Powered Flexible Electroosmotic Actuator for Wearable Haptics

Wearable haptic actuators are important to provide users with tactile feedback to enhance immersive human-machine interaction. Most of the existing actuators, although soft and small, typically work at a high voltage of kilovolt level, which brings about safety risks for users. In this work, via functional group modification on a piece of glass fiber membranes, we construct a flexible electroosmotic actuator that can operate at a voltage as low as 20 volts, falling at the safe voltage for the human body. The actuator delivers feedback forces exceeding the tactile perception threshold of human skin and maintains stable performance in 2500 cycles. We also constructed a haptic patch that satisfies the two-point discrimination threshold at fingertips by arranging actuators with an interspacing of 3 mm. Integrating the haptic patch into a VR system, we demonstrate its ability to reproduce complex tactile sensations and enhance immersion, showing the potential of the actuator strategy in safe operation and accurate communication in immersive human-machine interaction.