Skin-integrated haptic interface system based on a stretchable pressure sensor array for wireless tactile visualization applications

Haptic interfaces offer extraordinary capabilities in facilitating tactile and kinesthetic interactions between virtual environments and the real world, thereby revolutionizing the way humans experience bodily sensations in the context of embodied intelligence. A fundamental component in the burgeoning field of haptic interface systems is the tactile sensor, which incorporates pressure-sensitive materials and flexible electrodes. However, the mechanical mismatch between multiple layers, stemming from the diverse material moduli, presents a persistent challenge in developing robust tactile/pressure sensors with reliable interfacial stability. Here, we present a novel stretchable pressure sensor featuring an adaptive modulus design of sensitive layers, effectively addressing the issue of heterogeneous interfacial concerns, such as delamination, between the sensitive materials and electrodes. The incorporation of a highly stable interface confers upon the pressure sensor an exceptional level of sensitivity (96.1 kPa⁻¹) and linear response (R²>0.995) across a broad pressure range (up to 123.1 kPa, closely approximating the sensitivity of human skin). The skin-integrated haptic interface system, composed of stretchable pressure sensor array and multichannel data acquisition circuit, enables the perception of pressure distribution feedback by visualizing the electrical signal contour at different locations within the virtual reality scene in a wireless manner. Looking forward, such haptic interface systems, enabling highly reliable tactile sensing performance, will have significant potential for a wide range of applications in facilitating seamless interactions between humans and computers and enhancing immersive experiences.