To develop an otological robot that can protect important organs from being injured.
We developed a five degree-of-freedom robot for otological surgery. Unlike the other robots that were reported previously, our robot does not replace surgeon's procedures, but instead utilizes human–robot collaborative control. The robot basically releases all of the actuators so that the surgeon can manipulate the drill within the robot's working area with minimal restriction. When the drill reaches a forbidden area, the surgeon feels as if the drill hits a wall.
When an engineer performed mastoidectomy using the robot for assistance, the facial nerve in the segmented region was always protected with a more than 2.5 mm margin, which was almost the same as the pre-set safety margin of 3 mm.
Semi-manual drilling using human–robot collaborative control was feasible, and may hold a realistic prospect of clinical use in the near future.