Design And Implementation Of Cutter Head Components Welding Robot System Based On Structured Light Vision

The shield machine is a major power in the construction of rail transit,and the cutter head component is one of the core components that determine the performance of the shield machine.Aiming at the problems of low efficiency,low degree of automation,and inability to guarantee quality in the welding process of domestic cutter head components,this paper designs and implements a cutter head components welding robot system based on structured light vision.The system has multiple intelligent functions such as welding seam feature recognition,trajectory planning preprocessing,welding trajectory planning,automatic multi-layer and multi-pass welding,and is equipped with a reasonable human-computer interaction interface to enhance the application experience of industrial field operators,which greatly improves the the automation degree and efficiency of cutter head components production.The main work of this paper is as follows:1.The overall scheme design of the system.In view of the problems faced by the welding process of the cutter head parts and the actual application requirements,we design the overall scheme of the welding robot system for cutter head parts and divide the system into four parts:structured light vision system,control system,robot execution system,and welding system.Then the structure and function of each part of the system is introduced,and the on-site layout of the system as well as the welding workflow of the system is designed.2.System hardware and communication network design.Based on the overall design of the system,taking precision,efficiency,stability and reliability as the starting point,the main hardware devices of the system such as the structured light vision sensor,industrial computer,PLC,robot control cabinet,industrial robot,positioner and welding power supply are selected and configured.Finally,the communication network of the system is built and the hardware platform of the system is designed.3.Design of system software.Based on image preprocessing,laser stripe centerline extraction,feature point recognition and other processing procedures,the weld feature recognition program is designed to complete the preliminary acquisition of weld feature point information.By the principle of spatial coordinate transformation,the calculation program of coordinate ascending conversion matrix is designed to complete the rapid calculation of the conversion matrix required for mapping the feature point information of the weld to the three-dimensional robot tool coordinate system.We propose a correction method based on projection transformation,and design a preprocessing program for trajectory planning to correct the feature point information of the weld and the welding gun posture before the welding trajectory planning starts.A track planning strategy based on layer planning is proposed,and a multi-layer and multi-path welding track planning program is designed based on this method,so that the system has the ability to independently plan multi-layer and multi-pass welding trajectories when performing automated welding operations.According to the role played by the control system in the whole system,the PLC program and the robot control program are designed,and the upper monitoring interface of the control system is designed at the same time.4.Implementation and testing of the system.Based on the design method proposed in this paper,the cutter head components welding robot system is realized,and the main functions of each part of the system are tested.At the same time,an experimental automatic welding test is carried out for the cutter head components.The results show that the structure and function of this system are complete.The welding efficiency of this system for cutter head components is nearly 4 times that of the manual welding systems,and the welding qualification rate is above 95%.Considering the design and implementation process of the system and the final test results,the welding robot system designed in this paper provides a valuable development direction and application case for the intelligent upgrade and transformation of the existing cutter head components manual welding system.