Test of a Tube-Shaped Artificial Skin Sensor Array for Colonoscopies

Thin-film stretchable sensors are believed to have a great applications on devices with curved surfaces. As one type of these sensors, electronic skins (e-skins) for pressure measurement have the potential to provide protection to the human body by feeding back the contact pressure. One of the applications is to monitor the contact pressure from a colonoscope to the colonic wall during a colonoscopy to prevent perforation and hemorrhaging. Many studies have reported the highly flexible and stretchable nature of e-skin sensors. However, no effort has been made to investigate their performance in a colon simulator. In this paper, we developed a new technique to make ultra-thin, highly stretchable electrodes on thin films. Then we successfully built a three-layer tube-shaped tactile sensor with high conformability and stretchability. We then investigated the pressure generated by various bending curvatures on a colonoscope. Finally, we performed a real-time pressure measurement with the whole sensing system on a fake colonoscope in a colon-simulator. The measured pressure was obtained and visualized on a computer screen. These experiments validated the applicability of the designed sensor and revealed the actual stress distribution on a tube-shaped e-skin sensor array in a colon-simulator. This research could be the starting point of the effort to upgrade the strategies of colonoscopy for safer operations and could provide new routines to optimize tactile sensor design for other medical applications.