并联臂增材制造机器人滑模变结构运动控制系统研究  

Sliding Mode Variable Structure Motion Control for Additive Manufacturing Parallel Manipulator

作　　者：孙辉辉 张玉洁 钱森[2] 张伟杰 SUN Hui-hui;ZHANG Yu-jie;QIAN Sen;ZHANG Wei-jie(College of Mechanical and Electrical Engineering, North China Institute of Science and Technology, Langfang Hebei 065201,China;College of Mechanical Engineering, Hefei University of Technology, Hefei 230009,China)

机构地区：[1]华北科技学院机电工程学院,河北廊坊065201 [2]合肥工业大学机械学院,合肥230009

出　　处：《组合机床与自动化加工技术》2019年第8期109-112,125,共5页Modular Machine Tool & Automatic Manufacturing Technique

基　　金：国家自然科学基金青年基金(51605126);廊坊市科学技术研究与发展计划(2018011007)

摘　　要：针对增材制造成型零件高精度高性能的需求,为了进一步降低成型零件的形位误差和表面粗糙度值,文章搭建了并联臂增材制造机器人运动控制平台,基于滑模变结构控制理论,提出一种适用于不确定性机器人的智能控制方法。该方法首先对系统的运动学和动力学进行建模,得到机器人运动学雅可比矩阵,利用拉格朗日功能平衡法,构建出存在外部扰动和不确定项的运动控制模型,克服了并联臂机器人解耦困难的问题;然后,基于状态偏差和各阶导数变化,构建滑模控制函数,通过不断调整系统自身结构,使其始终沿着设定的超越曲面运动,增强控制系统对外部扰动的鲁棒性,实现不确定系统的精确控制。最后,利用数值仿真及试验,验证控制系统的可行性,从成型零件表面粗糙度和形位公差两方面与常规PID控制方法进行比较,试验结果表明,表面粗糙度值Ra和Rz降低了40%左右,形位公差值降低了30%左右,控制精度高于常规PID控制方法。In view of faults of the current additive manufacturing parallel manipulator such as low accuracy of motion control and poor anti-jamming, a nonlinear control system for uncertain robot is proposed in this paper based on the sliding mode variable structure control theory. The control system can accurately control the motion of the robot by changing the structure of the control system according to the motion error. Firstly, the kinematics and dynamics of the robot are modeled by the basic configuration of the robot. On this basis, the input vector and sliding mode function of the control system are determined, and the motion controller of the sliding mode variable structure system is designed. The system is proved to be stable through the Lyapunov function. Finally, the feasibility of the control system is verified by numerical simulation and experiment. The proposed method is compared with the conventional control method in terms of surface roughness and shape and position tolerance. The experimental results show that the surface roughness values of Ra and Rz are reduced by nearly 40%, the tolerances of shape and position are reduced by nearly 30%. The performance of the control system is better than that of the conventional control method.

关 键 词：并联臂机器人 动态建模 控制系统 滑模变结构 

分 类 号：TH165[机械工程—机械制造及自动化] TG659[金属学及工艺—金属切削加工及机床]