Bio-inspired triboelectric nanogenerator as a self-powered gait recognition sensor for legged robots
Reducing dependency on external energy sources for gait recognition systems in legged robots is critical for extending operational endurance in field transport and emergency rescue. This study presents a performance-enhanced triboelectric sensor with a tilted magnetic microneedle surface (TMMS-TENG), inspired by the tilted microstructures on mantis forelimbs. By integrating magnetorheological materials with micro-engineering, the tilting and bending of microneedles are controlled via magnetic field direction and intensity, significantly modulating the sensing signal. The TMMS-TENG achieves a peak output power of 5.82 mW at a load resistance of 3 MΩ, with high sensitivity (7.57 kPa⁻¹ in the 0–1 kPa range, 3.55 times higher than planar structures), fast response (loading: 61.3 ms; recovery: 50.8 ms), and high stability. When the microneedle tilt angle is 25°, sensitivity remains at 1.19 kPa⁻¹ in the 1–11 kPa range. The sensor demonstrates outstanding recognition capability and stability in legged robot gait recognition, offering potential for robotics, intelligent manufacturing, and health monitoring. This approach reduces reliance on external power, enhancing flexibility and energy efficiency in field operations.