Active tremor compensation in microsurgery

This work presents the development of an intelligent microsurgical instrument to perform real-time tremor compensation within a handheld tool. The intelligent instrument senses its own motion, distinguishes between voluntary and erroneous motion, and manipulates its tip to cancel the undesired component in real-time. The on-board sensing unit is made up of a magnetometer-aided all-accelerometer inertial measurement unit and sensor fusion is performed via a quaternion-based Kalman filtering. Tremor is modeled and filtered by an adaptive zero-phase notch filter. The intraocular shaft manipulator is a three DOF piezoelectric actuated mechanism driven by a feedforward controller with inverse rate-dependent hysteresis model. Laboratory experimental results of the system are presented.