GaN/PDMS-based opto-electro-mechanical tactile sensors.

Tactile sensors are crucial in robotics and medical diagnostics, requiring precise real-time detection. However, the development of a compact sensor that can measure force across a wide range, with high resolution and rapid response along three axes, remains extremely limited. Herein, an opto-electro-mechanical tactile sensor is reported, utilizing a monolithically integrated GaN-based optochip with a fingerprint-patterned polydimethylsiloxane (PDMS) film. The sensor exhibits a linear response over a broad measurement range of ±100 mN for shear force and 0-200 mN for normal force, with a detection resolution of 0.07 mN. It also demonstrates fast response and recovery times of 0.85 ms and 0.82 ms, respectively. Experimental verification of its application in surface topography scanning and organ lesion assessment highlights its potential for enhancing robotic perception and medical diagnosis.