一种微小挠性零件的自动化精密装配系统

为解决具有挠性结构微小零件精密装配的问题,将基于机器视觉的精密测量技术、高分辨率非接触激光位移测量技术等应用到精密装配系统的研制中.设计了用于微小零件夹持的装置,实现了对微小挠性零件拾取、搬运、放置等操作;根据视觉系统测量得到的微小零件与目标位置的偏差,对微小零件水平面内的位置和姿态进行了调整;提出了装配微小零件挠性结构的接触控制方法,该方法通过激光位移传感器非接触测量挠性结构接触变形所引起的微小位移变化,实现了装配过程中垂直方向的精密接触控制;通过在作业机械臂上集成标定模板,实现了装配系统的自动标定.简要介绍了所研制的装配系统组成,并进行了微小挠性零件的装配实验.实验结果表明,微小零件装配的平行度、同轴度误差小于10 μm,挠性结构接触控制偏差为0.6 μm ～0.8 μm,装配精度满足使用要求.

Automatic precise assembly for miniature elastic parts

In order to solve the problem of precise assembly of miniature parts with elastic structures,the precision measurement based on the machine vision,the high resolution non-contact laser displacement measurement and other technologies were applied to the automated precise assembly system.The fixture used for gripping the miniature parts was designed for carrying out the operations of pick up,move and placement.According to the position and orientation error measured by the vision system between the miniature part and its target location,the miniature part was adjusted in the horizontal plane.The precise contact control method in assembly of miniature parts with elastic structures was put forward.Non-contact laser displacement sensor was used to measure the micro displacement caused by the contact deformation of the flexible structures.By integration of the mask template into the manipulator arm,the automatic calibration of the assembly system was realized.The developed assembly system was briefly introduced,and the assembly experiment was done.The experiment results show that,both of the parallelism and coaxial errors of the miniature parts assembled are less than 10 μm,and the contact position control error during assembly of the flexible structures are between 0.6 μm ～ 0.8 μm.The assembly accuracy can meet the requirements.