An ultra-thin and lightweight flexible actuator for digitally-controllable shape-morphing haptics

Abstract

With the growing demand for wearable electronics, efficient haptic systems are essential for contact perception and variable haptic feedback. However, achieving a large shape-morphing haptic output is still a challenge for existing flexible robotic actuators. This paper presents a digitally-controllable, ultralight (65mg), ultrathin (260 μm) flexible actuator that delivers large shape-morphing haptic feedback with an output force of 240 mN and a displacement of 0.88mm. By integration of micro-circuit printing and micro-fluidic manufacturing technologies, the actuator with significant lightweight and thinness is created. Despite excellent flexibility, the actuator is still able to generate powerful haptic output. User experiments with a haptic signal recognition accuracy of 91.33% validate its potential in wearable devices and human-machine interfaces. Additionally, immersive virtual reality experiments confirmed its ability to recreate realistic tactile sensations, such as perceiving continuous water flow and catching a fast-moving object, highlighting its applicability in embodied intelligence, virtual reality, motion training, and interactive experiences. This study offers new design insights for haptic interfaces in virtual and augmented reality and lays the foundation for future skin-patch-based haptic devices.