Endoscopic Path Planning in Robot-Assisted Ear Surgery Based on Improved A-Star Algorithm

Preoperative planning is crucial in transcanal endoscopic ear surgery (TEES), especially with the increasing advancement of robot-assisted surgical systems. However, current preoperative path planning largely relies on the surgeon's experience. To address this, a preoperative path planning method based on an improved A* algorithm is proposed in this paper. First, an optimized search space method is introduced by accounting for the endoscope’s size and dimensions. Second, turning constraints are incorporated into the cost function to ensure that the planned path meets surgical requirements. Finally, a cubic B-spline is employed to smooth the curve, generating a safe surgical path from the ear entry point to the target surgical area. Simulation results demonstrate that the improved A* algorithm can efficiently find a feasible path in a short time, effectively keeping the planned path away from obstacles while reducing path length and the number of turns, thereby enhancing the safety and stability of robot operation in TEES.