Redundant Robot Kinematics Error Analysis for Neurosurgical Procedures

This paper explores the kinematic relation between the robot configuration in joint space and both the robot tool center point (TCP) position resolution and the robot end-effector orientation resolution with the purpose of reducing error. In the context of the use of redundant robots in neurosurgery for the placement of deep SEEG electrodes in the skull of patients suffering from epilepsy, this reduction in the error of the TCP would result in greater safety of this procedure and a consequent reduction in the possibility of surgical complications. The mechanical redundancy of the robot populates a null space where suitable joint configurations can be analyzed. In simulation, when comparing the joint configuration that obtained the smallest Cartesian error with the largest, there was a reduction of 50.23% in the Cartesian error. The results confirm the expected error disparity for different joints configurations, while the robot TCP is kept in the same position and the end-effector holds the same orientation. Our error analysis method could lead to a decrease in the risks involved in the procedure of SEEG electrode placement in neurosurgery.