Wearable Ionic Sensor with 3D Mesh Design for Human Finger Enclosure

A wearable sensor emulating human skin has been developed, with applications in healthcare monitoring, human-machine interfaces, and robotic skin. To ensure good adherence to human skin, soft and stretchable polymer-based sensors have been created. However, these sensors can easily fall off when the skin stretches due to joint movement, necessitating additional adhesive techniques to keep them securely attached.<br/>In this study, we propose a cylindrical mesh-type ionic sensor designed to be worn on the finger. The cylindrical shape provides a stable fit regardless of finger movement, and the mesh structure offers excellent air permeability and minimal resistance to movement. We utilized 3D printing to manufacture these sensors, overcoming the limitations of conventional methods. By configuring the printer’s bed into a tubular shape, we achieved 360-degree printing of mesh-shaped ion gels that wrap snugly around the finger.<br/>These printed ionic sensors ensure a secure fit, enabling precise monitoring of strain without any looseness between the sensor and the finger. Additionally, by adjusting the size and structure of the printer’s tubular bed, we can produce sensors tailored to fit various curvatures and sizes of objects, including fingers, forearms, knees, and feet. This cylindrical mesh-type sensor holds significant potential for use in various fields where stable integration of sensors onto curved surfaces is challenging.