Proximity Servoed Minimally Invasive Continuum Robot for Endoscopic Interventions

Abstract

Minimally invasive continuum robots face limitations in accessing environmental and spatial information on the situs. However, such information would often be necessary for control and automation features in surgical use. Centering an endoscopic system within a hollow organ can be such a feature, providing the benefit of reduced risk of injury and assistance for navigation. To leverage such an application, this work investigates a proximity servoed continuum robot. A sensorized tip combines capacitive electrodes, a camera, and illumination and uses capacitive proximity sensing to determine the enclosing environment’s center point. A controller is presented that uses this information to center the robot’s tip. The system is evaluated in a dynamic phantom, where an average accuracy of 10.0 mm could be demonstrated and contact to the phantom’s wall was avoided during 98% of the experiment time. In a second phantom experiment, it is demonstrated how this controller can be applied to follow the center line of a bent anatomical structure. Future work should focus on improving accuracy and versatility of the system, aiming for application in more challenging and irregular environments, such as ex vivo or in vivo organs.