Highly stretchable multimodal sensor with split-line structural design for adaptive robotic grippers

A large-area multimodal sensor device integrating pressure, temperature, humidity, proximity, and bending sensors was developed on a stretchable and flexible substrate. The substrate combines rigid polyimide with a soft elastomer to enhance stretchability, achieving up to 127% elongation through split-line structural designs that effectively relieve stress concentration. After 1,000 stretch-release cycles at 30% strain, resistance variation remained below 0.48%, confirming excellent mechanical durability. The pressure sensors exhibited high sensitivities of 27.5 kPa⁻¹ (8-channel array) and 9.2 kPa⁻¹ (18-channel array) across a wide pressure range, demonstrating suitability for robotic gripper applications. The central sensing units accurately measured bending (R² = 0.998), environmental parameters, and object distance with verified functionality. Overall, the device exhibits robust, reliable, and highly stretchable multimodal sensing performance, offering strong potential for advanced robotic manipulation and environmental monitoring applications. A split-line patterned stretchable substrate was developed to mitigate slimming and crack formation, achieving 127% elongation, over threefold improvement compared with conventional designs. The integrated multimodal sensor platform (pressure, bending, temperature/humidity, proximity) maintained stable sensitivity and electrical continuity under 30% strain and 10³ stretch cycles. The simple layout-level split-line strategy enables mechanically robust and wafer-compatible fabrication of next-generation adaptive robotic e-skin systems.