OmniSense v2: A Human-Skin Inspired Visuotactile Sensor for Unified Tactile Imaging

Visuotactile sensors have emerged as promising tools for digitizing the sense of touch, but most existing platforms remain limited to specific modalities such as high-resolution geometry, slip detection, or thermal cues, requiring reconfiguration or trade-offs in functionality. In contrast, human skin simultaneously perceives multiple modalities within a single surface. This work introduces OmniSense v2, a compact human-skin inspired visuotactile sensor that integrates multimodal tactile imaging into a unified gelatin-based elastomer layer. The elastomer incorporates UV-fluorescent markers for deformation tracking, thermochromic pigments for categorical temperature sensing, and a Lambertian surface coating for high-contrast texture imaging. These are paired with a programmable RGB/UV LED illumination system and a global-shutter vision module. Dedicated algorithms emulate the mechanoreceptive pathways of Merkel cells, Ruffini endings, Meissner and Pacinian corpuscles, and Aδ and C fibers through normal force mapping, tangential force classification, vibration measurement, surface imaging, and stepwise temperature sensing. Experimental evaluations demonstrate reliable normal force distribution mapping, >96% accuracy in slip, shear, and torque classification, vibration detection between 1–6 Hz, categorical thermal sensing across 15–75 °C, and a surface imaging resolution of 0.177 mm that surpasses human tactile discrimination (~0.4 mm). Stability tests showed functionality for six months, reusable calibration, and variability within ±5-12% across modalities. Latency was low for most tasks, with tangential sensing slower and higher variance (50-100ms). Furthermore, a handheld, time-multiplexed demonstration further illustrates near-simultaneous readouts of multiple modalities. These results position OmniSense v2 as a versatile visuotactile platform capable of capturing biologically mimicked tactile information across multiple modalities without mechanical reconfiguration.