Achieving Biocompatibility in Soft Sensors for Surgical Robots

Abstract

INTRODUCTION Minimally invasive surgical robotics has enabled clinicians to operate with reduced trauma due to small incisions and long, slender tools. Instrument guidance remains a limiting challenge, however, for procedures in which image quality is limited and haptic feedback is unavailable, e.g., beating-heart intracardiac procedures [1]. To address this need, our group has been investigating sensing technologies that can envelop a robot with a compliant sensing structure and provide clinicians with tissue contact and force information over its entire surface including its tip. Soft sensors are a particularly promising candidate technology that, to date, have not been considered for medical applications. These sensors are composed of a compliant polymer structure containing channels filled with a conductive liquid. Under load, the channel cross sections deform providing pressure or strain measurements measured as changes in resistance [2].