Structural Design And Control System Research Of Ship Surface Crawling Welding Robot

In the context of economic globalization,the shipbuilding industry has developed rapidly in recent years.Welding is a key process technology for connecting ship hull structures,which directly affects ship manufacturing efficiency and service safety.At present,the welds of hull welding have large curvature and long length,and the welding environment is complicated.Most of the welds need to be completed by manual welding.The magnetic adsorption crawling welding robot can be adsorbed on the metal wall of the ship to replace workers to perform welding tasks.It has the advantages of high operating efficiency and stable welding quality.At present,the existing ship welding crawling robots have relatively weak adaptability to the ship surface environment,and the different shapes,inclinations,protrusions,depressions,etc.of the ship surface will affect the stability and accuracy of welding.Based on the above problems,this paper proposes and designs a crawling welding robot suitable for ship surface structures,and conducts a systematic study on its control system.This paper first analyzes the actual working condition requirements of the ship curved surface crawling welding robot,and determines that the ship curved surface crawling welding robot needs to adapt to the large curvature of the hull and overcome the hull surface obstacles.According to the requirements,the overall plan design of the ship curved surface crawling welding robot is carried out.The key technologies of the mechanical body and the drive system,such as the wheel-foot hybrid structure,the magnet adsorption scheme,the curved surface adaptation device,and the selection of the motor and welding machine,are studied.By introducing a multi-index comprehensive evaluation method,the overall evaluation of the robot program is carried out to test the rationality of the design process.Secondly,based on the special working conditions of the crawling welding robot on the surface of the ship,the robot often needs to move along a specific path on the surface of the ship to ensure that it can successfully complete the task.In order to realize the robot control system,this paper designs a robot path planning system based on the six-wheel differential model,and uses the improved pure-pursuit algorithm to obtain the global optimal path.The simulation results show that the path obtained by improving the pure-pursuit algorithm can give priority to ensuring the safety of the robot’s work,and has a high degree of fit with the reference path.Further,in order to achieve precise control of the crawling welding robot on the curved surface of the ship,it can move freely and perform tasks on the surface of the hull.In this paper,a robot control system based on CAN(Controller Area Network)bus is built,and a distributed control network based on CAN bus is designed.The distributed control network utilizes the industrial computer to monitor and control each node on the CAN bus.The main control interface and main control program of the ship surface crawling welding robot are developed on the industrial computer using C# language in the Visual Studio software development environment.The operator can realize the human-computer interaction with the robot through the main control interface on the industrial computer,so as to achieve Precise control of curved surface crawling welding robot.Finally,the designed ship surface crawling welding robot prototype is trial-manufactured and assembled,and its motion function and perception function are tested.The test verifies the design rationality of the robot and the feasibility of the control scheme.The results show that the robot has a strong ability to adapt to the ship surface environment,can adapt to the large curvature of the ship hull and overcome the obstacles on the ship surface,and can replace manual work in various functions,and has the ability to perform welding operations on the ship surface.