| Welding is a key process for automobile manufacturing.Promoting the automation and intelligence of welding have a great significance to improve the quality of automobiles and reduce manufacturing cost.Welding robot can achieve high-strength,high-precision,high-stability welding operations,and increasingly used in automotive manufacturing.In this paper,in order to realize the automatic welding of the inner quarter panel of automobile,the design and application of the spot welding robot workstation are studied,The structure design,path planning,motion simulation,and control system design of the spot welding robot workstation are completed.The main content of this paper include the following aspects:First,the overall design of the spot welding robot workstation is carried out according to the technical characteristics and production requirements of the inner quarter panel of automobile.The number of stations,station distribution,overall dimensions,and key equipment types of the spot welding robot workstation are determined.The welding fixture positioning and clamping mechanism are studied.The design of the welding fixture is completed by using CATIA software.The rationality of the welding fixture design is verified by the finite element analysis technology and ergonomics principle.Secondly,the improved ant colony algorithm is used to carry out path planning for the spot welding robot workstation of the inner quarter panel of automobile.Considering the requirement of minimum changes in position during welding process and the shortest welding path of the spot welding robot,a grouping method is used to deeply study the path planning of the workstation.A three-dimensional TSP mathematical model of the robot welding path is established and a MATLAB program is developed to solve the problem.In order to solve the problem that the ant colony algorithm is easy to fall into the local optimal solution in the path planning of spot welding robot workstations,the method of applying hybrid particle swarm optimization algorithm to cross and mutation operations to generate new individuals is proposed to improve the ant colony algorithm.For the problem that the ant colony algorithm performance over-relates on the parameter setting,the orthogonal parameters and regression analysis are used to optimize the relevant parameters.Compared with other algorithms,the results show that the improved ant colony algorithm has faster convergence speed and better path in solving the problem of spot welding robot path planning.Thirdly,Roboguide software is used to simulate the welding process of the spot welding robot workstation,to check whether there is interference phenomenon,and to verify the rationality of parameter setting and the welding rhythm.Roboguide off-line programming capability is used to generate off-line programs that improve the efficiency of spot welding robot workstation.Finally,the control system of the spot welding robot workstation of the inner quarter panel of automobile is designed.The structure of the control system of the spot welding robot workstation,the selection of key control equipment,and the design of the operation panel are discussed.The key screens of the touch screen and the key procedures of the PLC are explained.The control system not only can realize the automatic welding of the spot welding robot workstation,but also has the functions of workpiece in-position detection,electrode automatic grinding,safety alarm,etc.It has the advantages of high safety factor,simple operation and good quality assurance.The research contents,methods and conclusions of this paper provide ideas for solving problems that currently arise in the design and application of robot welding workstations,such as irrational structural design,random path planning,and lack of control system functions,and provide reference for R & D,design and application of other robot welding workstations. |
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