Designing, Prototyping, and Testing a Flexible Suturing Robot for Transanal Endoscopic Microsurgery

Abstract

Suturing and knot tying in a confined space is a technically challenging yet clinically demanding task in minimally invasive surgery, which requires the use of highly articulated instruments passing through small incisions on the patient's body. Manually operating such instruments is usually very difficult, so robot-assisted methods have been introduced to reduce the burden of the surgeon. In this letter, a robotic suturing system for simplifying suturing in a confined space is proposed. The main part of the suturing robot is a 6-mm flexible suturing instrument that consists of suturing probe and a customized flexible joint. A novel needle driving and locking mechanism have been proposed. For controlling the suturing robot with teleoperation, the kinematics of the robot and its differential Jacobian as well as inverse kinematics are provided. A working prototype of the suturing instrument is built and integrated into a teleoperated suturing system. Running stitch and knot tying experiments have been conducted to evaluate the robot's feasibility for suturing in a confined space, which mimics the transanal endoscopic microsurgery procedure.