一种应变片装配系统的校准方法

为了解决机械臂装配系统中基座坐标系难以确定及空间位置获取时需进行运动学建模的难点，提出了一种基于工具坐标的偏差式计算方法用于应变片装配。通过工作坐标与弹性体装配孔中心位置重合校准，将应变片偏差与弹性体偏差投影至工具坐标系，建立了装配系统的偏差计算模型。通过基于质心的绕贴装头中心旋转且等角度分布于圆周上的多幅图像信息，使贴装头中心定位和坐标重合点精确到亚像素级精度，实现了高精度贴装头位置和坐标点重合校准。实验结果表明该系统能很好地完成应变片的自动装配任务，6 s完成一次应变片的安装，且装配精度能达到0.2 mm。

A Calibration Method for Strain Gauge Assembly System

In order to solve the difficulties of confirming base coordinate system in the process of manipulator assembly and carrying on kinematics modeling when acquiring spatial location,a deviation calculation method for strain gauge assembly based on tool coordinate method is propesed.The deviation of strain gauge and elastomer is projected to a tool coordinate system,and the deviation calculation modeling of assembly system is established by coinciding with work coordinate and elastomer mounting holes center.The position of high precision mounting head coincides and is calibrated with the coordinate system point through rotation around mounting head center based on mass center and pieces of image information of uniform angles distributed on the circumference for the sub pixel precision accuracy of mounting holes center positioning and coordinate system coincidence points.The experiment results show that this system can perfectly complete the task of strain gauge automatic assembly with 6 seconds each times and precision of 0.2 mm.