Smith Predictor Based Control In Teleoperated Image-guided Beating-heart Surgery

Surgery on a freely beating-heart is extremely difficult as the surgeon must perform the surgical task while following the heart’s fast motion. However, by controlling a teleoperated robot to continuously follow the heart’s motion, the surgeon can operate on a seemingly stationary heart. The heart’s motion is calculated from ultrasound images and thus involves a non-negligible delay estimated to be 100 ms that, if not compensated for, can cause the robot end-effector (i.e., the surgical tool) to collide with and puncture the heart. This research proposes the use of a Smith Predictor to compensate for this time delay. The results suggest that heart motion tracking is improved as the introduction of a Smith Predictor decreased the mean absolute error, difference between the surgeon’s motion and the distance between the heart and surgical tool, and mean integrated square error.