Enhanced flexibility and dexterity in robotic endoscopy via a 6-DOF parallel mechanism and eye-gaze-assisted field-of-view control

Abstract

In conventional minimally invasive surgery, an assistant manually steers the endoscope based on the surgeon’s verbal commands, but fatigue and tremor can degrade field-of-view (FOV) stability and efficiency. Robotic endoscopes address this limitation through automated FOV adjustment via image-based visual servoing, ensuring smooth and stable visualization. However, most robotic implementations mount rigid straight-rod endoscopes on external serial arms, limiting dexterity and complicating remote-center-of-motion (RCM) control. Moreover, many automated FOV methods track surgical-tool tips without representing the surgeon’s intention. This work therefore presents a compact 6-DOF parallel endoscopic mechanism that improves flexibility and dexterity while simplifying RCM constraint satisfaction, together with an eye-gaze-assisted multi-tool tracking controller that dynamically weights tools according to surgeon attention. Simulations and experiments across diverse scenarios demonstrate FOV stabilization within 2 s, mean image-space tracking error $<$ 20 pixels, eye hand error $<$ 3°, and at least a 30% reduction in unnecessary FOV adjustments. Supplementary video is available.