Development Of A Robot System For Grinding Weld-beads Of Aluminum Alloy Train Body

With The constant pursuit of lightweight for high-speed train body，aluminum alloy train bodyalso gets more and more attention andapplication.The aluminum alloy train body is mainly welding andassembling with large structure parts, so we need to study on the processof welding the aluminum alloy train body and grinding the weld bead. Nowthe research on welding technology of aluminum alloy has made remarkableachievements, the welding process automation has been part of therealization. But the research on post processing of welding seam stillremain in original stage, with traditional manual grinding way. It s notonly time-consuming and difficult to guarantee the consistency ofprocessing quality, but also very harmful to workers’ health. The subjectdeveloped a robot system to grinding weld-beads of aluminum alloy trainbody, to replacing the manual process. It apply many advanced techniques,such as the of mobile robot, vision sensing and motion control. The robotsystem can realize the automation of the grinding process, and reduce theworkers’ labor strength and improve the grinding quality and workingefficiency.Firstly, this paper introduces the manufacturing process of aluminumalloy train body, and emphatically analyzes its welding and grindingprocess, toconclude the function requirement of grinding robot.With thecompared of many plans, we design a tooling system with a simple toolchanger, which use servo system as the drive. The feed mechanism is composed of two vertically linked linear modules. The structure of walkingmechanism is crawler-type combined with multi-suckers. Finally，we startlayout and assembly of the overall system, completing the model ofgrinding robot.We need to select the appropriate servo motor, linear module and stepmotor, after the main design of construe is complete, by analyzing andcalculating the stress condition in the robot work condition. The finiteelement statics analysis and modality analysis have been carried out onthe important component of robot. It shows that structural damage willnot happen on the existing structure, through the checking results of thestrength and stiffness. The security and reliability of the robotstructure also is verified.A complete grinding robot system is not only the mechanical structureparts, should also include the control system. The structure and functionsof control system are investigated based on the industrial PC with themotion control card. The control hardware consists of microcomputer,servo drivers, servo motors, stepping motor, stepping motor driver andso on. The control software adopting modularization designing method todevelop a friendly interface based on the VC program environment. It canrealize the automation of welding line grinding.Finally, the grinding experiments on the6005aluminum alloy weld withthe robot system are studied. The goal of these experiments is to researchthe working performance of the developed grinding robot, which directedthe future research. The mathematical model of material-removal rate iscalculated, which is based on the model of weld. Then we can research theinfluence on grinding efficiency by the grinding time, grinding depth,transverse feed and grinding speed, andanalyze its cause. Theexperimental results show that it is reasonable and effective for thedeveloped robot to grinding the aluminum weld.