Kansei Imagery-Based Coupled Bionic Design for Hand Rehabilitation Robots

Current hand rehabilitation robots often exhibit limitations in structural compactness, ergonomic compatibility, and aesthetic appeal, failing to satisfy users' dual demands for functionality and visual sophistication. This study proposes a Kansei Imagery-driven coupled bionic design method, which systematically translates user emotional needs into biomimetic forms by integrating Kansei Engineering, Extension Theory, and eye-tracking experiments. Core perceptual imagery—"minimalistic," "aesthetic," and "technological"—was first extracted through lexical screening and cluster analysis. The crab was subsequently identified as the optimal biological prototype via user research and entropy weight analysis. An Extension correlation model was then constructed to quantify the matching degree between crab biological characteristics and the hand rehabilitation robot across morphology, function, and environmental adaptability, guiding design optimization through Extension reasoning. Concurrently, based on an analysis of the hand's musculoskeletal configuration, a novel four-loop ten-bar planar linkage transmission mechanism was developed, achieving high-fidelity replication of natural finger motion trajectories. The final design was validated through eye-tracking experiments and semantic differential scales. Results demonstrated superior performance in visual attention distribution, affective semantic communication, and wearable compatibility. This work validates the feasibility and effectiveness of the Kansei Imagery-driven coupled bionic design approach, offering a novel framework and methodological support for the emotional and human-centric design of hand rehabilitation robots.