Single-Leader Guided Dual-Follower Robotic Cooperative Motion for Retinal Surgery by Virtual Constraints

Traditional retinal surgery requires surgeons to simultaneously manipulate both surgical instruments and an intraocular light guide, a process that poses challenges due to the need for precise coordination. This article addresses the challenge of dual-follower robotic cooperative motion in retinal surgery through the development of a single-leader guided dual-follower robotic cooperative motion strategy. By establishing virtual intersection point constraints, a single leader efficiently guides both the operation arm and the light guide arm to achieve cooperative movement. In addition, we propose a tracking deviation evaluation method and a deviation compensation model to enhance the tracking accuracy of the light guide arm. The effectiveness and superiority of the proposed method are validated through fixed trajectory tracking experiments and cooperative operation experiments. Fixed trajectory experiments were conducted to compare light guide arm tracking performance among manual operation, a kinematics method, and our proposed method. The results show that the proposed method achieved an average tracking deviation of 1.66 mm, outperforming existing research methods, which reported an average deviation of 2.45 mm. Furthermore, the dynamic time warping (DTW) and Hausdorff distance between the instrument trajectories and the spot trajectories in microscopic images were measured at 7.47 and 0.034, respectively. These findings demonstrate that our method significantly reduces the tracking deviation of the light guide arm, ensuring stable tracking performance. Cooperative operation experiments further illustrated the effectiveness of our planning method in providing varying lighting effects appropriate for different stages of surgery, with smooth transitions between each stage. Overall, these results not only highlight that our method offers higher tracking precision and stability, but also underscore its significant potential for coordinating the motion of dual-arm robots. Consequently, this approach serves as a robust technical foundation and theoretical support for future multiarm robotic-assisted ophthalmic surgery.