Research On New Motion Plan Method For CRDM Nozzles' Mobile Welding Robot

Welding of nozzles on pressure vessel is a key problem in nuclear plant establishment.Upon now,this part of weld is mainly conducted by workers' manual manipulation,which is often low efficiency and unwarranted.Funded by national natural science foundation of China,this paper presents the research on the welding between pressure vessel and nozzles,proposes a new complete plan of welding robot in this scenario and studies the robot motion plan.Firstly,weld space between pressure vessel and nozzles is narrow,weld shape is complex,and the whole work space is grand.This paper conduct the mathematical modeling of working environment.Proposes two proper welding robot type plans,undetached hexpod robot and detached hexpod robot.Moreover,to meet the requirements of high efficient real-time motion algorithm,this paper proposes a new gait plan method which has a topology-parameter-trajectory three level structure.In topology part,finish the gait type plan.In parameter part,finish the gait feature definition,namely the height,length,time and radius.In trajectory part,optimize the gait trajectory.Take advantage of three level gait plan method,efficiently reduce the computing load of robot,raise the online plan speed and provide online plan algorithm for incoming real-time feedback vision control robot manipulation under complex working condition.Next,mobile welding robot moving route and weld trajectory are subjected to study.Three sweep modes,namely horizontal,diagonal and radial,are proposes to finish all the nozzles welding.Realize the welding trajectory of welding gun.Based on all the research done in this paper,this paper introduces and designs a welding robot motion plan system for user to control the whole system.Meanwhile,the data experiment is conducted,verifying the whole plan's feasibility.