摘要
为了提高冗余自由度机械臂的运动准确性,进行基于全局最优滑模控制器的冗余自由度机械臂运动控制的研究。分析冗余自由度机械臂的机械结构,明确其结构组成及运动原理。通过各关节节点的旋转角度及连接臂长度,分别求取了相邻关节节点间的旋转关系式及关节结点相对基础坐标的移动矢量,并通过该移动矢量得出机械臂的动力学方程。通过机械臂的动力学方程,计算出单个关节节点的系统方程。利用角度误差构造滑模面,并在此基础上利用单个关节节点的系统方程,建立滑模控制器。为了获取滑模控制器中滑模加权因子和趋近加权因子的最优解,采用粒子群算法在解空间中对其进行全局搜索,从而得到全局最优化的滑模控制器,用于对冗余自由度机械臂的运动过程进行控制。实验中,采用此方法和干扰观测器方法对关节节点的运动过程及末端执行器的运动过程进行了控制,从控制结果可知:在控制关节节点及末端执行器运动时,此方法比干扰观测器方法的控制准确度分别提高了17.12%和13.49%,表明此方法能有效保障冗余自由度机械臂的运动准确性。
In order to improve the motion accuracy of the 5-DOF manipulator, the motion control of the 5-DOF manipulator was researched based on the global optimal sliding mode controller. The mechanical structure of the 5-DOF manipulator was analyzed, and its structure composition and motion principle were clarified. Through the rotation angle of each joint node and the length of the connecting arm, the rotation relationship between the adjacent joint nodes and the movement vector of the joint node relative to the basic coordinate were obtained respectively, and the dynamic equation of the manipulator was obtained through the motion vector. The system equation of a single joint node was calculated through the dynamic equation of the manipulator. The sliding surface was constructed by using the angle error, and the sliding mode controller was established by using the system equation of a single joint node. In order to obtain the optimal solution of the sliding mode weighting factor and the reaching weighting factor in the sliding mode controller, the particle swarm optimization algorithm was used to search for the global optimal sliding mode controller in the solution space, which was used to control the motion process of the 5-DOF manipulator. In the experiment, the motion process of the joint node and the end effector were controlled by the proposed method and the disturbance observer method. From the control results, the control accuracy of the proposed method is 17.12% and 13.49% higher than that of the disturbance observer method respectively. It shows that the proposed method can be used to guarantee motion accuracy of the 5-DOF manipulator effectively.
作者
屈海军
杨森
QU Haijun;YANG Sen(School of Mechanical Engineering,Jiangsu College of Safety Technology,Xuzhou Jiangsu 221011,China;College of Materials Science and Engineering,Liaoning Technical University,Fuxin Liaoning 123000,China)
出处
《机床与液压》
北大核心
2021年第5期45-49,共5页
Machine Tool & Hydraulics
基金
辽宁省教育厅科学研究项目(L2013138)。
关键词
冗余自由度机械臂
运动控制
滑模控制器
粒子群算法
全局最优解
5-DOF manipulator
Motion control
Sliding mode controller
Particle swarm algorithm
Global optimal solution
