Continuum tactile sensing via an amplified liquid metal interface.

Abstract

Multimodal tactile sensing is crucial for next-generation robotics and human-machine interaction, but conventional solutions based on discrete sensor arrays suffer from complexity, limited flexibility, and high fabrication costs. Here, we introduce a continuum sensing paradigm based on a continuous liquid metal enabled flexible tactile sensing (CLiMETS) platform. This approach eliminates the need for sensor arrays by decoding tactile information from a single, unstructured liquid metal (LM) surface. We reveal a key mechanism where the deformation-induced voltage of the LM's electric double layer (EDL) is synergistically amplified by over two orders of magnitude upon contact with a conductive rod. Our geometrically encoded, dual-channel scheme enables precise 5 by 5 localization and eight-directional sliding recognition. We further demonstrate the platform's feasibility by realizing postprocessing visual feedback of an LED array, effectively translating complex tactile inputs into corresponding optical outputs. The CLiMETS platform offers a minimalist yet highly versatile proof-of-concept sensing modality, laying a strong foundation for more adaptive and interactive tactile technologies.