Gradient‐Structured Hydrogel with Integrated Actuation and Strain Sensing for Biomimetic Robotics

Abstract The development of soft robotics that integrates autonomous motion and real‐time sensing remains challenging due to the irreconcilability of these functions in homogeneous materials. Inspired by natural symbiotic systems, a conductive nanocomposite hydrogel is developed that achieved a synergistic combination of magnetic actuation and built‐in strain‐sensing capabilities through a facile magnetic‐field‐induced assembly strategy that creates a gradient distribution of Fe 3 O 4 @MXene nanohybrids within the hydrogel network. The resulting hydrogel exhibits a comprehensive set of properties underpinning this synergy: good conductivity (2.6 mS cm −1 ), high strain sensitivity (gauge factor of 6), a broad strain response range (0–580%), and excellent fatigue resistance (500 cycles), along with a fast magnetic actuation speed of 30° s −1 . The core advance is that actuation and sensing work in concert within a single material, allowing it to execute programmed deformation while simultaneously monitoring its own motion in real‐time, which is vividly showcased through biomimetic applications, such as a gripper that adjusts its grip upon sensing and a crawler that can track its own movement. This work provides a paradigm for creating intelligent soft matter with innate feedback loops, opening transformative avenues in adaptive soft robotics, biomedicine, and human‐machine interaction.