Positioning accuracy analysis and error compensation of medical robot assisted for mandible reconstruction surgery

In order to improve the accuracy of the mandible reconstruction robot, the positioning accuracy and error compensation was studied using NDI Polaris based on analysis of surgery procedure. The kinematics parameters were identified based on a revised D-H kinematics model, taking small distortions of the joint axes and link parameter into consideration. Joint transmission error and zero position error were compensated with experiments. Absolute positioning accuracy of the robot was measured using an accurate NDI Polaris measure device according to the model. The experiment results show that the maximum value and the mean value of the absolute positioning accuracy are much better than the previous values after compensating the errors caused by link parameter, transmission and zero position. The method can be widely used in series robot error compensation.