3-PPSR并联微动机器人静刚度分析  

Static Stiffness Analysis of 3-PPSR Parallel Micromanipulator

作　　者：荣伟彬[1] 王乐锋[1] 孙立宁[1] 

机构地区：[1]哈尔滨工业大学机器人研究所,哈尔滨150080

出　　处：《机械工程学报》2008年第1期13-18,24,共7页Journal of Mechanical Engineering

基　　金：国家自然科学基金(50605013);哈尔滨工业大学优秀青年教师培养计划(HITQNJS.2006.032)资助项目。

摘　　要：为简化6支链并联微动机器人的复杂结构,减小装配误差,提出压电陶瓷驱动的3-PPSR构型6自由度并联微动机器人结构。采用整体式下平台和三条两端带有柔性球铰链和直圆柔性铰链的支杆,使结构紧凑并有利于提高精度。为分析对并联微动机器人精度具有重要影响的静刚度指标,首先求出此类机器人的逆解矩阵及支杆柔性铰链处微小角位移和末端位姿的关系。在此基础上,考虑支杆两端柔性铰链和弹性平板的弹性变形,运用虚功原理推导并联微动机器人静刚度矩阵。进而仿真分析机构各几何参数对静刚度的影响,获得支杆两端铰接点半径及直角弹性平板和支杆两端柔性铰链尺寸对刚度的影响规律,为此类并联微动机器人刚度配置和机构优化设计提供理论依据。A 3-PPSR parallel micromanipulator with 6-DOF driven by piezoelectric actuators is presented to avoid the complex structure and reduce the assembly error of the usual 6-limed ones. It is very compact and helpful to improve the accuracy using the monolithic bottom stage and only three fixed-length rods with flexure hinges at the two ends. To analyze the static stiffness, which is an important index that affects the accuracy of the manipulator, the inverse kinematics and the relation between the end-effectors＇ position and pose and the micro deformation of the flexure hinges is derived from series of coordinates transformations firstly. As to the elastic deformation of the flexure hinges, the static stiffness matrix of the manipulator is developed via the principle of virtual work. Based on this model, the influence of the parameters for the stiffness of the manipulator is discussed. Thus the effect of the radii of the hinge circles and the dimensions of the flexure hinges on stiffness are obtained. The results provide tutorial for configuring the stiffness and designing the structural parameters of the parallel micromanipulator further.

关 键 词：并联微动机器人 柔性铰链 静刚度 

分 类 号：TP242[自动化与计算机技术—检测技术与自动化装置]