摘要
柔性医用机械臂末端定位的精准性对放疗非常重要,针对柔性医用机械臂末端空间定位精度差这一问题,分析机械臂的关节减速器动态回转误差和连杆柔性引起的末端空间定位误差。利用拉格朗日法建立了柔性医用机械臂的动力学模型,分析RV减速器的动态回转误差,建立RV减速器摆线针轮回转副的啮合刚度模型;在关节传动误差与连杆柔性的耦合作用下建立柔性医用机械臂末端空间定位误差模型,采用近似方法对机械臂动力学模型进行逆动力学求解,并拟合得到RV减速器输出驱动力矩和臂杆模态响应函数,通过仿真对比分析关节减速器RVSHPR-110E、RV320E、RV40E,发现RV减速器的刚度越大其产生的关节传动误差越小,从而造成机械臂末端空间定位误差也就越小。研究为柔性医用机械臂末端空间动态定位误差的补偿提供了理论依据。
The accuracy of the flexible medical manipulator tail end positioning is very important for radiotherapy.For the problem of poor spatial positioning accuracy of the flexible medical manipulator tail end, the dynamic rotation error of the joint reducer of the mechanical robotic arm and the end space positioning error caused by the flexibility of the connecting rod are analyzed.The Lagrange method is used to establish the dynamic model of the flexible medical manipulator, to analyze the dynamic rotation error of the RV reducer, and to establish the meshing stiffness model of the cycloidal pin wheel rotation pair of the RV reducer.The spatial positioning error model of the end of the flexible medical manipulator is established under the action of the coupling of the joint transmission error and the link flexibility.The inverse dynamic solution of the manipulator dynamic model is solved by an approximate method, and the function of the output driving torque of the RV reducer and the modal response of the robotic arm is obtained by fitting analysis of the joint reducer RVSHPR-110E,RV320E,RV40E.The results show that the greater the rigidity of the RV reducer, the smaller the joint transmission error, the smaller the positioning error of the end space of the robot arm and the end space of the flexible medical robotic arm.The compensation for dynamic positioning errors provides a theoretical basis of the flexible medical manipulator tail end.
作者
张鹏
陈惠贤
裘应驰
雷武乐
李双
ZHANG Peng;CHEN Huixian;QIU Yingchi;LEI Wule;LI Shuang(College of Electrical and Mechanical Engineering,Lanzhou University of Technology,Lanzhou 730050,China)
出处
《甘肃科学学报》
2022年第5期18-25,共8页
Journal of Gansu Sciences
