Linkage Couples Based Endoscope-holder Robot with Enhanced Bending Curvature for Laparoscopic Surgery

Endoscope provides visualization and access to internal organs, regarded as a crucial instrument usually held by surgical assistants in minimally invasive laparoscopic surgery. However, handheld endoscopy poses challenges like operator fatigue, instability, and limited dexterity, potentially compromising procedure accuracy and efficiency. Meanwhile, rigid straight endoscopes lack flexibility, limiting their effectiveness in navigating complex anatomical structures and tight spaces during minimally invasive surgeries (MIS). To provide surgeons a stable and flexible endoscope view and enhance the efficiency of the endoscopy procedures, we present a linkage couples based endoscope-holder robot. A linkage mechanism based on linkage couples was designed as the bendable structure to steer the endoscope. The bending range was enlarged by accumulating linkage couple units. An actuation package mounted on a robotic arm, providing two degrees of freedom (DoFs) for the movement of the endoscopic device, enabling both bending and rotation of the endoscope. The bending range and the resistance to deformation ability were validated on the 3D-print robot prototype, reporting large bending range exceeding -180 deg to 160 deg and 100 g workload. Model experiments demonstrated the ability of the endoscope-holder robot to bypass obstacles and search targets in a constrained space. The advent of bendable endoscope-holder robots is expected to provide a more stable and flexible surgical view for minimally invasive procedures, thereby facilitating efficient and effective surgeries.