Research On Hole Position Correction And Trimming Technology Of Wing Panel Based On Laser Scanning Data

Panels are usually positioned based on skeleton in wing assembly. During the traditional process of wing assembly, the wing panel drilling mainly depends on artificial measurement and marking to ensure the hole positions and drilling margins, while the panel trimming also uses the way of artificial marking and artificial polishing. However, the method is inefficient and imprecise. Besides, when dealing with composite panel, the operating environment on site, which affects workers’health, is terrible. This paper relies on a project assumed by Zhejiang University, and the project is based on digital measurement technology and researches on the problem of drilling hole margin and trimming on the panel deeply. In order to provide reasonable hole positions for drilling robot, the hole position correction based on hole margins and Shepard interpolation is realized and the characteristics of original hole distribution ranks are retained. The trimming trajectory of panel is calculated based on the boundary of skeleton, which can be provided for programing in NC machining system.In the paper, the research status of wing digital assembly at home and abroad and the application of digital measurement technology and automation drilling technology in wing digital assembly are introduced firstly. The structure of wing, process requirement of assembly and difficulties during assembly are presented. Then wing scanning measurement subsystem of wing digital assembly system is introduced.For the over tolerance of hole margin, the definition and elements of hole margin are given firstly. A correction method for hole positions based on hole margin constraints and Shepard interpolation is proposed. An example is provided to prove the effectiveness of the method.For the problem of panel trimming during finishing of wing assembly, trimming trajectory is generated by projecting the feature points on boundary of skeletons into point cloud of panel using k-d tree search algorithm. The build step of trimming program for NC machining system is given. The availability of the method is proved by an example.Then, a special scanning measurement plug-in is developed based on PolyWorks IMInspect module. It can control Laser Tracker and T-Scan to collect point cloud data and process point cloud data to realize hole position correction and calculate trimming trajectory.Finally, summary for the whole work in the paper is given and the future work is discussed.