神经外科机器人定位精度研究

针对机器人辅助神经外科手术对高精度的要求，对“黎元”神经外科机器人的定位精度进行了研究．考虑到关节轴的微小偏差，基于修正的DH运动学模型对机器人的实际几何参数进行了辨识．采用基于误差反传（BP）算法的多层前馈神经网络对各关节的传动误差进行了补偿．利用高精度的三坐标测量臂对“黎元”神经外科机器人的定位精度进行了测量．结果表明，该机器人绝对定位精度最大值为1.63 mm，平均值为1.04 mm，较以前有了很大提高，能够满足多数神经外科手术的需要．

On the Positioning Accuracy of a Neurosurgical Robot

In order to meet the requirements for high accuracy in robot-assisted neurosurgery,this paper studies the positioning accuracy of our neurosurgical robot,NeuroMaster.Taking small distortions of the joint axes into consideration,the kinematic parameters are identified based on a revised Denavit-Hartenberg kinematic model.A multilevel feedforward neural network based on error backpropagation(BP) algorithm is used to compensate the transmission error of each joint.Posi-tioning accuracy of the robot is measured using an accurate three-dimensional measuring device.The result shows that the maximum value of the robot positioning accuracy is 1.63 millimeters,and the mean value is 1.04 millimeters,which are much better than the previous values.The robot can satisfy the requirements of most neurosurgical operations.