Research On Dual-robotic Synergic Drilling And Riveting System

The application of automatic drilling and riveting technology greatly improves the efficiency of aircraft assembly, and ensures assembling quality and the life of airplane. Dual-robot drilling and riveting system, for its unique advantages, is becoming an important direction in automatic drilling and riveting industry. As a result, the development of dual-robot synergic drilling and riveting system is crucial in Chinese aviation manufacturing industry. Against this background, investigations are done in this thesis to solve some questions existing in dual-robot synergic drilling and riveting system, which demonstrates the feasibility of robotic drilling and riveting.Firstly, the development and application of automatic drilling and riveting technology and some equipments are summarized. Based on this background introduction, the significance of the research, as well as the main points in this thesis are given in chapter1.All the tests done in this paper are base on the dual-robot drilling and riveting platform, which is described in detail in following aspects, involving the structure and stiffness model of KUKA robot, main functions of robotic end-effector, the components in panel and its assembly model, laser tracker measurement system. There are two typical defects after some tentative riveting tests, one is the convex height couldn’t meet the requirements of riveting surface quality, the other is the driven rivet head are deformed more or less, which contributes to the poor performance in jointing and anti-fatigue strength.As to the first defect, researches show that vibration of bucking bar during riveting makes a difference. Thus dynamic model of robotic riveting system is established to analyze the vibration of bucking bar and robot’s end displacement. Results of analysis and experiments show that the displacement of robot is less than0.05mm, which could be ignored; also the vibration of bucking bar could be reduced once a higher spring stiffness and proper contact force between the bucking bar and skin are applied, thus improving the riveting surface quality.As to the second defect, kinematic modeling and simulation on the process of robotic percussive riveting are presented. The simulation results indicate that input pressure and riveting time has a great influence on riveting process, and the desirable driven head can be acquired as long as using proper input pressure and riveting time. Finally, by using electromagnetic valve to control the switch of pneumatic rivet gun, the riveting time can be controlled automatically. Combined with robot automatic drilling system, the moving path of robot is projected based on the specified riveting time, which makes dual-robot synergic drilling and riveting automation possible.