Spatial Registration for a Three-Arm Robot Assisted Mandible Reconstruction Surgery

The three-arm surgical robot system assisted mandible reconstruction surgery (TMR-MRS) is developed to repair the mandible defects caused by congenital defect, trauma, or acquired disease. The surgical robot system is divided into four parts, including 3D reconstructed image subsystem, robotic subsystem, optical measurement subsystem, and patient subsystem. The spatial registration based on quaternion is proposed to obtain the transformation relationship between four surgical subsystems. A method of hand-eye coordination is presented to control the end-effector of the robot arm to target position according to surgical planning. A least square error criterion is developed to optimize and compensate the hand-eye coordination method. In addition, the position of fibular implant in the robot space is calculated when it is grasped by end-effector of robot middle arm. Finally, the positioning accuracy tests and skull model experiments were conducted to evaluate the function of the surgical robot system. The results validate its feasibility and are consistent with the preoperative surgical planning.