Teleoperative control of intraocular robotic snake: Vision-based angular calibration

Lack of dexterity is one of the major challenges in retinal microsurgery because of the limited intraocular space and physical constraints of surgical tools in the current practice. Snake-like robots, therefore, have the potential to address this limitation. Their dexterity can reduce the (otherwise inevitable) eyeball manipulations to reach the target tissue and increase the workspace using the fixed sclerotomy port, which can result in an easier operation and less tissue damage. In the current study, we present the new version of our integrated intraocular snake (IRIS) robot - a sub-millimeter snake robot with 2DOF rotational motion at the tool tip. Real-time computer vision was used to measure the tip pose. Calibration of the tip bending angle based on the wire translation (motor rotation) was performed in the entire workspace of the robot combining its yaw and pitch motions. The robot is teleoperated from the master console (Phantom Omni) in an intuitive scheme so that the robot tip follows the motion of the user's hand with an angular accuracy of ±0.2°. Experimental results indicate that users were able to reach the target in about one minute and their performance improved in the subsequent trials.