平面3-■RR刚柔耦合并联机器人逆动力学研究  

Research on the inverse dynamics of the planar 3-■RR rigid-flexible coupling parallel robot

作　　者：赵新华[1] 王嘉斌 刘凉[1] 张青云[1] 戴腾达 史晨阳 ZHAO Xin-hua;WANG Jia-bin;LIU Liang;ZHANG Qing-yun;DAI Teng-da;SHI Chen-yang(National Demonstration Center for Experimental Mechanical and Electrical Engineering Education,Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control,Tianjin University of Technology,Tianjin 300384)

机构地区：[1]天津理工大学天津市先进机电系统设计与智能控制重点实验室机电工程国家级实验教学示范中心

出　　处：《机械设计》2019年第11期6-13,共8页Journal of Machine Design

基　　金：国家重点研发计划资助项目（2017YFB1303502）;天津市应用基础与前沿技术研究计划资助项目（17JCYBJC18300）;天津市大学生创新训练计划资助项目（201810060013）;天津市教委科研计划资助项目（2017KJ259）

摘　　要：以平面3-RRR刚柔耦合并联机器人为研究对象,研究了其逆动力学模型和数值迭代求解算法。以绝对节点坐标法描述并联机器人中的柔性梁单元,并以自然坐标法描述其他刚性构件,基于拉格朗日原理构建了刚柔耦合系统的逆动力学模型。采用了缩减积分的方法来分割应变能以规避泊松闭锁问题,应用不变矩阵来提高求解运算速度。以S-型加减速圆周轨迹为算例,结合generalized-Alpha法与牛顿迭代法来求解并联机器人的逆动力学模型。试验迭代结果满足设定精度要求,所求柔性梁中点处最大横向变形为4.701 mm,其剪切角的变化规律具有对称性,驱动关节角速度与理想刚性模型相比变化明显,驱动关节变量的变化规律比较平滑,由此验证了建模方法、求解算法的正确性和使用S-型加减速的必要性,对将来控制具有重要的理论意义。In this article,both the inverse dynamic model and the numerical iterative algorithm are explored for a planar 3-RRR rigid-flexible coupling parallel robot.The flexible beam element in the parallel robot is identified by the absolute nodal coordinate,and the other rigid members are identified by the natural coordinate.The inverse dynamics model of the rigid-flexible coupling parallel robot is set up based on Lagrange principle.The strain energy is split with the aid of the reduced integration method,in order to avoid the problem of Poisson locking;the invariant matrix is adopted to greatly improve the computing speed.By the simulation with a circular trajectory of S-type acceleration and deceleration,the inverse dynamic model of the parallel robot is solved by combining the generalized-Alpha method with the Newton iterative method.The results of experimental iteration satisfy the setting precision,and the maximum transverse deformation at the midpoint of the flexible beam is 4.701 mm.The law of the changing of the shear angle at the midpoint of the flexible beam has symmetry,and the angular velocity of the driving joint changes obviously,compared with that of the ideal rigid model.The driving-joint variables change smoothly.Therefore,the modelling method with the solution algorithm proves feasible,and it is necessary to adopt the S-type acceleration and deceleration.It is of great theoretical significance for the control in the future.

关 键 词：3-RRR平面并联机器人 刚柔搞合 绝对节点坐标 自然坐标 不变姐阵 generalized-Alpha法 

分 类 号：TH113[机械工程—机械设计及理论]