Path Planning of Robot-assisted Osteotomy in Orthognathic Surgery

As a critical process of orthognathic surgery, the osteotomy position of the maxillary bone is strictly defined in the preoperative plan, and it has a guiding function for the reposition of the bone. However, the manual operation is unable to implement the preoperative plan during the surgery. Therefore, the robot is introduced to assist surgeons to complete the osteotomy under the guidance of preoperative plan. The system design is described, and a path planning method is established for the robot assisted osteotomy in this paper. Firstly, the cutting line on the preoperative plan 3D model is extracted and transformed to the robotic coordinate. Then, the geometric path is calculated using a cubic b-spline approximation curve fitting. Finally, the pose of the tool is designed based on the geometric path. A simulated osteotomy is completed to verify the effectiveness of the method, the experimental results show that the planned path is smooth, and the velocities and accelerations are both continuous.