Modular continuum robotic endoscope design and path planning

Abstract

Robotic endoscopes have the potential to help endoscopists position tools during procedures, to propel the endoscope to the desired position, to automate functions and to prevent perforations during procedures. This paper outlines the modular architecture for a continuum robotic endoscope with multiple bending segments along the length of the endoscope. Each of the segments is modular, containing a set of actuation motors that drive short cables in the continuum segments. Each modular segment of the robot is 15 mm in diameter, can turn 180 degrees and has a turning speed ranging from 35 to 250 degrees per second. The robot is composed of seven of these modular segments, has 14 degrees of freedom, is 0.91 m long and has a mass of 157 grams. The implementation for the mechanical, electrical, and software design is described and the robotic endoscope bending motions are sensed, simulated and controlled using kinematic models. Lastly, path planning trajectories of the endoscope segments are designed and coordinated to help propel the robot forward in an uncoiling motion and in a follow-the-leader fashion along a path that emulates simplified turns in a colon. We show that the robotic endoscope is able to exert less force on the walls of the colon emulation path, enable automated insertion into the patient, and execute colon wall avoidance and linear scanning motions not available in conventional endoscopes.