The System Design Of Steam Generator-assembly Robot

Now, the application of robotics to component assembly is getting more and moreattention, especially to peg in hole assembly between two large parts. This topic stemsfrom the customer need to realize the steam generator unit automated assembly.According to the steam generator unit assembly process and analyzing assemblingdeviation and compliant assembly method in peg in hole assembly, the thesis comes upwith overall solution including mechanical structure, electrical control and detectionmethod.Mechanical structure: this thesis designs assembly robot with7degrees of freedomand fixture for artifacts under the inventor software. To ensure that the structurestiffness and strength meet the requirements, the thesis carries out nonlinear finiteelement analysis for the key parts under Algor analysis software. Based on matlabrobotics toolbox, the thesis carries out kinematics simulation and path planning ofassembly machine, to provide the basis for the control part.Detection and guidance: Preliminary testing before assembly and accuratedetection when assembling. It is preliminary testing that to detect the position of thehole axis in the machine coordinate system by two laser sensors scanning hole edge ofpressure vessel which are installed on arm part. Accurate detection is that six lasersranging sensor installed on the shaft at the top of the workpiece detects the distancebetween sensors with wall of hole. Then according to the distance difference, robotprecisely corrects the posture of work piece.Monitoring and control system: lower computer using Schneider M258controller,upper machine using industrial control computer. According to the assembly process,this thesis design PLC program to control the servo motor to complete the automaticassembly. Man machine interface is designed on host machine by configurationsoftware to realize real time monitoring and control of the assembly process. PCcommunicates with PLC via Ethernet, PLC communicates with servo drives throughCANopen Bus. Coaxial detection software is developed and designed under the.NETplatform to finish data processing form, human interface design, communication with control system.The equipment has completed assembly test in the simulation of the pressurevessel. The assembly effect fulfills the requirements of assembly. And the equipmenthas gotten pre acceptance.