Toward human-like touch sense via a bioinspired soft finger with self-decoupled bending and force sensing

The sense of touch means not only detecting force passively but also effortfully moving our fingers to touch and “feel” the world. Existing soft robotic hands can produce hand-like movements but are still far behind in terms of their sensing capabilities. Here, we propose a bioinspired soft finger (BSF) with self-decoupled bending and force sensing via a seamlessly integrated conductive fiber coil. By measuring the inductance and resistance, bending angle and force at the fingertip can be obtained with high resolutions of 0.02° and 0.4 mN, respectively. Both the sensing and actuation of the BSF have a response time (50 ms) comparable to that of human fingers and are mechanically durable for practical applications. The BSF can achieve a human-like touch sense of object stiffness and identify lumps underneath “normal tissues” by simply pressing it. Moreover, it can automatically locate the artery at a participant’s wrist and take the pulse. [Display omitted] •A bioinspired soft finger with proprioception and tactile sensing•A self-decoupled bimodal sensor with high performance and mechanical durability•Human-finger-like softness detection by monitoring the bending and exerted force•Demonstration of the soft finger for lump searching and pulse-taking like a “robodoctor” Inspired by the human hand, Wang et al. propose a bioinspired soft finger with self-decoupled bending and force sensing via a seamlessly integrated conductive fiber coil. The bioinspired soft finger is capable of human-like object softness detection by a simple touch and is demonstrated for lump examination and pulse-taking like a “robodoctor.”