直线超声电动机驱动并联平台建模与控制  

Modeling and Control of Parallel Manipulator Driven by Linear Ultrasonic Motors

作　　者：张泉[1] 朱本亮[2] 周丽平[1] 金家楣[1] 张建辉[1] 

机构地区：[1]南京航空航天大学机械结构力学及控制国家重点实验室,南京210016 [2]华南理工大学机械与汽车工程学院,广州510640

出　　处：《农业机械学报》2014年第7期278-285,共8页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金资助项目(91223201;51375225;51175264;51275235);中央高校基本科研业务费专项资金资助项目(NE2013001);江苏省自然科学基金资助项目(BK2012797);江苏高校优势学科建设工程资助项目

摘　　要：为实现直线超声电动机驱动的3-PRR并联平台的精确轨迹跟踪控制,对其进行了运动学和动力学建模,并设计了基于模型和轮廓误差的控制器。首先,根据并联平台的闭链约束条件,对并联平台进行了运动学分析。在此基础上,对并联平台的各部件速度和加速度进行了推导,并获得了相应的雅可比矩阵,随后基于虚功原理建立了平台的动力学模型。最后,由切线近似法推导了平面三自由度轮廓误差的转化方法,并设计了基于模型和轮廓误差的控制器。实验结果表明,基于动力学模型和轮廓误差的控制器可将X和Y轴的轨迹跟踪误差控制在15μm以内,提高了动平台的轨迹跟踪精度。The dramatically due demand for to their role precise positioning manipulators with a large workspace has increased in semiconductor manufacturing, medical surgery and automatic microassembly. In this paper, a planar parallel manipulator （PPM） actuated by three linear ultrasonic motors （LUSMs） for high accuracy positioning is designed. With the aim to realize accurate trajectory tracking control of the proposed 3-PRR PPM, a model and contour error based controller is developedaccording to the dynamic model of the parallel manipulator. The dynamic modeling procedure is as follows： firstly, based on the closed-loop constraints of the parallel structure, kinematic analysis of the manipulator is carried out, and the inverse kinematics solution is obtained. Then thevelocities and accelerations of each part, such as rigid linkage, sliders of the motor, and the moving platform, are analyzed in order to derivethe corresponding Jacobian matrices between different coordinates. Finally, the dynamic model of the parallel manipulator is developed using virtual work principle. In a motion trackingtask, it is much more important to minimize the component of the error vector that is the normal with respect to the reference trajectory. This component of the error vector is referred to as the contour error. According to contour error theory, minimizing independent axial errors may not minimize the contour error and conversely, it is possible to have a small contour error while having large axial errors. Hence the contour error based control method is adopted to achieve precise motion tracking in this paper. The contour errorsof three planar degrees of freedom are formulated based on tangential approximation approach, and then a model and contour error based controller is developed using the feedback linearization principle. The stability of the proposed control law is proved based on Lyapunov theory. To guarantee the accuracy of the proposed control algorithm, a kinematic calibration is performed to obtain the real kine

关 键 词：直线超声电动机 并联平台 动力学模型 轮廓误差 

分 类 号：TP242[自动化与计算机技术—检测技术与自动化装置] TM359.4[自动化与计算机技术—控制科学与工程]