Design Of Mechanical Arm Terminal Sliding Mode Control System

With the development of modern aircraft manufacturing technology,the requirements of fatigue life,sealing and anti-corrosion are becoming higher and higher.In order to meet the requirements of aircraft performance,various advanced manufacturing technologies have been developed in the field of aviation manufacturing,among which the automatic riveting and drilling technology of robot connection technology is one of them.The application of riveting assembly technology in foreign countries for decades has proved that the assembly efficiency after automatic riveting is at least 10 times higher than that of manual riveting assembly.It can save installation cost and improve labor conditions.More importantly,it can ensure installation quality and greatly reduce the defects caused by human factors.Now the automatic drilling and riveting technology has become one of the main technological measures to improve the performance of aircraft.Automatic drilling and riveting technology is not only the requirement of mechanization and automation,but also the requirement of aircraft performance.With the continuous improvement of performance and level of new aircraft developed by China’s aviation industry,it is imperative to develop automatic riveting technology in riveting assembly process.The existing automatic drilling and riveting system in our unit has seriously restricted the scope of application of the system due to the impact force and positioning problem of the terminal actuator on the workpiece surface,so it is necessary to reform the equipment.On this basis,a set of robotic automatic drilling system based on composite wing components has been developed.In this paper,the actuator control system of the manipulator terminal has been studied and designed.The first chapter of this paper introduces the research background and significance of the subject,summarizes the status quo of robotic automatic drilling and riveting technology used in Aircraft Assembly at home and abroad,and gives the research content of this paper on the basis of expounding the application of terminal actuator in robotic drilling and riveting technology.In the second chapter,the processing requirements of composite wing components are introduced,and the requirements for terminal actuators are put forward.The structure,functions and characteristics of each part are introduced in detail.Finally,the automatic drilling process of robots is analyzed.Chapter 3 introduces the structure of the terminal actuator,designs and reforms the distance sensor of the existing equipment.Through the problem of impact force produced by pressure foot acting on the surface of parts,a buffer control method for pressure foot control is proposed,and a synovial control system is designed.Taking distance as control input and displacement of pressure foot as control feedback,a fully closed-loop control system is constructed to realize fast positioning of pressure foot and reduce impact force.At the same time,the distance sensor can adjust the processing attitude of the robot to improve the accuracy of hole-making.In the fourth chapter,the synovial control system is studied,and the synovial control algorithm is proposed through the establishment of the pressure foot aerodynamic model non-linear model.In the fifth chapter,through the experimental content and results,the performance indicators of various aspects are analyzed,and the feasibility of the system is proved.Chapter 6 summarizes the work of the whole paper and looks forward to the next step.