基于视觉的大尺度部件相对位姿实时测量方法研究

相对位姿是装配过程中的一项重要监控项。针对大尺度部件对接过程中的相对位姿测量需求,提出了一种基于视觉的相对位姿实时测量方法。该方法利用单目视觉技术,通过采集合作靶标的图像,实时解算大部段间的相对位姿,用于辅助大尺度部件的装配。首先,设计了一套相对位姿实时测量系统,包括搭载单目相机的视觉测量单元,以及用于辅助位姿解算的合作靶标;其次,对相对位姿测量的完整流程进行了研究,包含系统标定方法与实时位姿解算方法;最后,在实验室环境下对位姿测量系统的精度进行测试。试验结果表明,位姿测量系统在垂直于光轴方向的重复精度可达0.02mm,沿光轴方向重复精度优于0.2mm,输出位姿结果时间低于0.3s;对多测量单元组网测量进行了仿真计算,垂直于光轴方向的重复精度优于0.1mm,沿光轴方向重复精度优于0.2mm,输出位姿结果时间优于1.3s。试验结果表明,提出的方法可满足一般大尺度部件对接过程实时位姿监控与对接状态评估的需求。

Research on Real-Time Relative Pose Measurement Method of Large-Scale Components Based on Vision

Relative pose is an important monitoring item in the assembly process.Aiming at the relative pose measurement requirements during the docking of large-scale components,a vision-based real-time measurement method of relative pose is proposed.Based on the monocular vision technology,relative poses of sections is calculated in real time with the images of cooperative targets,which can be useful for the assembly work.Firstly,a real-time relative pose measurement system is designed,including a vision measurement unit equipped with a monocular camera,and a cooperative target for pose calculation.Secondly,the complete process of relative pose measurement is studied,including system calibration method and real-time pose calculation method.Finally,the accuracy of the pose measurement system is tested in laboratory.The result shows that the repeatability of the pose measurement system perpendicular to the optical axis can reach 0.02mm,the repeatability along the optical axis is better than 0.2mm,and the time of pose measurement is less than 0.3s.The network measurement of multi-measuring unit is simulated,and the repeatability perpendicular to the optical axis is better than 0.1mm,the repeatability along the optical axis is better than 0.2mm,and the time of pose measurenent is less than 1.3s,which satisfies the requirement of pose monitor and docking state estimation for large-scale component docking.