Design and Modeling of a Thin-walled Multi-segment Continuum Robotic Bronchoscope

Cable-driven continuum robots in bronchoscopic procedures hold immense potential to revolutionize the diagnosis and treatment of lung cancer. However, robotic bronchoscopes in current studies are typically large in size and inflexible. Therefore, this article introduces a novel cable-driven continuum robot bronchoscopy system that achieves modular design between the actuation and operation ends. A continuum structure with a dual-segment notched flexible skeleton, featuring a wall thickness of 0.45 mm, has been designed to perform bending movements exceeding 190°. This enhances flexibility and increases the spatial capacity of the working channels. A kinematic model was developed, integrating the actuation force and the mechanical characteristics of the driving cables for error compensation, estimating the correlation between the displacement of the driving cables and the position of the continuum robot’s end-effector. The verification showed that the root mean square error (RMSE) of the end-effector position is 2.57 mm, which accounts for 4.8% of the continuum’s length. A prototype of the robotic bronchoscopy system was created, and its performance and potential applications in bronchoscopic intervention surgeries were validated through vivo pig intervention experiments.