Wearable haptic interfaces enhance human–machine interaction by delivering tactile cues for object manipulation, touchscreen interaction, and remote‐control tasks. However, most existing wearable haptics encode directional cues relative to the actuator layout, which can cause inconsistent spatial interpretation when device orientation changes during natural limb motion. To address this limitation, we introduce a Pose‐Independent Haptic Ring (PIHR) that delivers joint‐referenced spatial cues using a compact, multichannel serpentine shape memory alloy (SMA) actuator array embedded in a stretchable elastomer. The device exploits a metacarpophalangeal (MCP) joint–centered spherical mapping scheme that associates four circumferential normal‐force channels with flexion, extension, abduction, and adduction, thereby preserving anatomical cue meaning under posture variation. Structural optimization identified the AD61–UD4 configuration as the most effective design for balancing force output, indentation stroke, and response speed within a ring‐scale form factor. Electrothermal characterization demonstrated stable pulsed operation and thermally acceptable performance under the tested condition. Human‐subject evaluation under dynamic posture variation showed an overall recognition accuracy of 79.2% without prior training. Proof‐of‐concept open‐loop demonstrations further verified the feasibility of the PIHR in tactile‐guided touchscreen interaction and vision‐integrated teleoperation. These results establish PIHR as a compact, pose‐independent wearable haptic platform for robust directional perception in interactive applications.
Kim et al. (Fri,) studied this question.