A dual-mode transparent flexible pressure sensor array for tactile sensing visualization

Flexible pressure sensors exhibit significant potential for applications in robotics, smart medical devices, and human–computer interaction; however, achieving transparency, high sensitivity, and multimodal perception simultaneously presents numerous challenges. In this study, we present a dual-mode transparent flexible pressure sensor array (DPSA) based on triboelectric and capacitive sensing principles. The sensor utilizes radio-frequency magnetron sputtering to deposit ITO films onto a flexible PET substrate, combined with a bilayer hemispherical PDMS elastomer to create a sandwich structure with high spatial resolution. This design enhances the sensor’s sensitivity and multimodal sensing capabilities by leveraging the change in contact area between the hemispherical PDMS array and the transparent electrodes. Utilizing a custom data acquisition system, the DPSA can monitor multi-touch and sliding trajectories in real time across a wide pressure range. In capacitive mode, the DPSA exhibits a sensitivity of 1.36 kPa⁻¹ and a response time of 3.9 ms at low pressure ranges; in triboelectric mode, it achieves a sensitivity of 0.25 kPa⁻¹ and a minimum detection limit of 0.3 Pa across higher pressure ranges. Experimental results demonstrate that the DPSA exhibits excellent performance in tactile sensing and external force detection, highlighting its significant potential for future applications in intelligent tactile systems and wireless human–machine interfaces.