Research On The Information Projectoin Technique For Manual Assembly Of Large Parts

The manual assembly of large parts,such as aircraft assembly,require accurate imformation of postion and dimensions about the fastener holes in the fasteners installation.Engineering and technical personnel need to read a lot of Work instruction,which makes the efficiency is low and easy to get wrong.Especially the assembly process and maintenance process information is not updated in time,it lead to great inconvenience for the assembly and repair process. Imformation projection technology for manual assembly of large part can solve the above problems well,it improve the assembly quality and efficiency,and then reduce production costs.Obtained the requirements of the work platform by analyzing the characteristics of manual assembly of imformation Optical projection.Established the framework of manual assembly Optical projection system connecting with the present research status of abroad and optical projection problems.Finally, determine the solution of the prototype syestem and the function module.First,the model building technology and representation of the optical projection guidance information was researched.Assembly guidance imformation mainly includes shape,text,image,which was organized and managed by three layer model.Whereby,part layer act as basic information layer,assembly layer act as attribute form or demand form of projection,guiding layer act as the real projection information.Established the task level model using for information representation.In the end,introduce the way of obtaining and planing all kinds of information.Based on light plane method for the projector calibration and the natural characteristics of the image for the camera calibration to realize the virtual-real registration on site. The scene virtual-real registration including camera and projector calibration and camera on-site registration. The camera on-site registration including static and dynamic registration. Static registration adopts the method which based on natural characteristics of the image to demarcate the camera external parameter. Dynamic registration extract and match the natural feature point between reference images and real scene images through a BRIEFalgorithm, which solve the real-time image camera pose information and realize the camera dynamic registration on site.Manual assembly of Optical projection system,which based on ugmented reality,was finished by OpenCV,Visual C++6.0 and Matlab.Analyzed the source of projection error and seek for solution of projective rectification. Experiments show that the system can complete assembly guide work steadily, so as to verify the validity of the theory and the feasibility of the method.