In minimally invasive robotic surgery the surgeon usually operates in front of a console with input devices. The single steps of the intervention are realized by transferring the movement of the input devices to the robots.
Demands on motion tracking of the input device are made with regards to accuracy, size of the working area, latency and robustness towards environmental influences. Usually these input devices consist of a mechanical assembly with links and joints, which are rigidly connected to the environment.
Another possibility is optical motion tracking. Among the advantages of optical motion tracking are a relatively large workspace and its high accuracy. However latencies caused by image acquisition and processing, and partial occlusions of the tracked objects, as they often occur during bimanual manipulation, have to be considered. By fusing optical data with accelerations and angular rates obtained from an inertial measurement unit and using controllable, active markers, the requirements can be met. The system should be usable as an alternative input modality for the surgeon or enable the assistant to undertake subtasks.
Florian Steidle, Andreas Tobergte, and Gerd Hirzinger, "Optical-inertial tracking with active markers and changing visibility" in Proc. of the IEEE International Conference on Intelligent Robots and Systems (IROS), Vila Moura, Portugal, October 2012. elib