• A research group led by Professor Sunkook Kim at Sungkyunkwan University, in collaboration with École Polytechnique Fédérale de Lausanne (EPFL), has developed a laser-processed three-axis force sensor and successfully integrated it into an ultra-light wearable haptic device named OriRing. The system enables finger-level, high-fidelity tactile feedback while maintaining the form factor and comfort of a simple ring.
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  Wearable haptic technologies are gaining increasing attention, particularly in combination with physical AI systems, as they offer new ways to convey sensations from virtual environments to the human body or assist physical interaction. However, conventional haptic devices largely rely on vibration or thermal stimulation, which limits their ability to realistically reproduce forces and material properties. Force-feedback systems that transmit forces at the joint level often suffer from bulky structures and heavy components, significantly reducing wearability. These challenges have driven strong demand for lightweight yet realistic haptic solutions.
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  To address these limitations, the research team developed a thin, flexible three-axis force sensor capable of precisely detecting multi-directional forces generated by finger movements. Using laser processing, the team formed micro-pyramid structures of varying heights on a polymer surface, allowing electrical signals to be clearly distinguished depending on the magnitude and direction of applied forces. Designed in a 2 × 2 pixel configuration, a single sensor unit can simultaneously measure both normal and shear forces, enabling true three-axis force sensing within an ultrathin form factor.
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  By integrating this sensor into OriRing, the researchers achieved an exceptional force-to-weight performance. Excluding the actuation module, the ring weighs only about 18 g, yet it can deliver up to 6.5 N of force feedback, equivalent to lifting a mass of approximately 663 g—a remarkable capability for a compact wearable device.
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  User studies confirmed that changes in the size and stiffness of virtual objects were instantly conveyed as tactile feedback in response to finger movements while wearing OriRing. Furthermore, the system demonstrated novel interaction modes in which users could dynamically modify the physical properties of virtual objects in real time using only finger motions.
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  “OriRing achieves accessory-level wearability while delivering superior force-to-weight performance compared to conventional glove-based haptic devices,” said Professor Kim. “This technology has strong potential for applications not only in virtual reality and gaming, but also in rehabilitation, medical devices, and teleoperated robotic systems.”
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  The results were published online on December 18, 2025, in Nature Electronics (Impact Factor 40.9; top 0.2% in JCR rankings).
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※ Title: An 18 g Haptic Feedback Ring with a Three-Axis Force-Sensing Skin

※ Journal: Nature Electronics

※ DOI: https://doi.org/10.1038/s41928-025-01515-x

※ PURE: https://pure.skku.edu/en/persons/sunkook-kim/

▲ A wearable haptic force-feedback ring with a three-axis force-sensing skin