Novel Design of a Surgical Tool Insertion Robot Using a Chebyshev Lambda Mechanism

Background: Endoscopic Retrograde Cholangiopancreatography (ERCP) and Percutaneous Coronary Intervention (PCI) are minimally invasive procedures that treat diseases with minimal scarring and rapid recovery. However, catheterisation under fluoroscopy exposes medical staff to radiation, and navigating flexible guidewires through complex anatomical pathways requires precise control. Methods: To address these challenges, we propose a novel insertion robot based on a Chebyshev lambda mechanism that makes a linear grasp path and an arc-shaped quick return path using a single motor. An integrated roll module enables continuous insertion and rotation, yielding a robot with two degrees of freedom. Results: Experiments show robots can make sufficient insertion force for real procedures, with robot's maximum mean translational and rotational errors of 0.11 mm and 1.47°, respectively. Phantom model tests show its applicability to human anatomy. Conclusions: The proposed robotic system demonstrated sufficient precision and force for real surgical applications, indicating its potential for clinical use in minimally invasive procedures.