Considering Normal Direction Constraints Real-Time Optimization Method for Active Optical Navigation System in Robotic Orthopedic Surgeries

Intraoperative optical navigation is an important technology in robotic orthopedic surgery. The optical tracking system (OTS) serves as the "eye" in intraoperative navigation and has a limited measurement volume (MV). When the position and attitude of the target tools fixed on the patient’s body or operation robot change, the target tools are easily moved out of the MV or the target tools cannot be seen by OTS, resulting in navigation failure. To solve this problem, we consider both the position and the normal direction constraints of the target tools, and incorporate them into the optimization formulation. In this article, a new real-time optimization method is proposed for changing OTS viewpoints in real-time to achieve continuous tracking of multiple dynamic target tools. Ultimately, simulation experiments are used to verify the effectiveness of the proposed real-time optimization method. When the position and attitude of the target tools undergo significant change, OTS can still continuously obtain measurement data from multiple dynamic target tools.