Design and Implementation of a Dual-Segment Continuum Waterjet Surgical Robot for Transurethral Bladder Ablation

Abstract

Bladder cancer is commonly treated by transurethral resection, but conventional rigid instruments provide limited distal dexterity and restrict access to anatomically complex intravesical regions. This paper presents a 5-DoF dual-segment continuum waterjet robot for transurethral bladder tumor ablation. The system integrates a high-pressure cavitating waterjet nozzle at the distal end of a 6-mm flexible arm, enabling independent bending and orientation control. A kinematic model and model-based tendon compensation method are developed to reduce proximal-distal coupling, and a master-slave control architecture is implemented for operator-commanded teleoperation. Workspace simulation, tendon coupling compensation tests, positioning repeatability measurements, and multi-site targeting experiments in a bladder phantom demonstrate the feasibility of flexible continuum manipulation combined with waterjet ablation for minimally invasive intravesical surgery.