Conformable core-shell fiber tactile sensor by continuous tubular deposition modeling with water-based sacrificial coaxial writing

Stretchable tactile sensors are popular in soft and conformable electronics, and innovations in their architectural design and manufacturing process are in demand for more advanced applications. In this work, a resistive-type core-shell tactile sensor was designed and fabricated via the coaxial ink writing of a continuous single core-shell fiber. Particularly, a facile tubular deposition modeling method was established, in which deionized (DI) water was selected as the core and first coextruded with the elastomeric shell and then scarified and replaced by injecting liquid metal (LM). To weave the continuous single core-shell fiber, tactile sensing nodes were formed easily and precisely to position-registered mechanical pressure stimuli. The resistive responses including sensitivity, coupling and reliability of the sensor architecture were examined, and the tracing mode was performed. Furthermore, the tactile sensor could be directly patterned on a 3D surface. The core-shell fiber-based tactile sensor design and its scalable manufacturing are significant for the advanced fabrication of 3D printed conformable electronics. (C) 2020 Published by Elsevier Ltd.