Structural Design And Control Research Of Wall-climbing Robot With Magnetic Particle Inspection For Ring-shaped Steel Structure

The hull needs to be constructed by welding large steel plates during the early manufacturing process.In order to ensure the welding quality of steel plates,magnetic powder inspection is required for the welds.Currently,most of them are manually inspected in the form of scaffolding.Manual detection has the disadvantages of low efficiency,high risk coefficient,and high labor intensity.With the development of wall-climbing robots and the automation industry,welding seam inspection robots have been studied and experimented to a certain extent.However,the problem of accurate seam inspection has not been solved under the condition of large curved surfaces.In view of the above,this paper designs a ring-shaped steel structure magnetic particle inspection wall climbing robot.The main research contents are as follows:1.Based on the working environment of the ring steel structure and referring to the technical parameter requirements,the robot’s adsorption mode,movement mode,drive mode,and detection mode were selected;the lifting mechanism,rotating mechanism and curved flexible adaptive force measuring mechanism of the detection device were designed;the image acquisition unit,dark environment and magnetic suspension spraying device were reasonably designed;the overall prototype of the robot was built.2.Based on the robot’s adsorption reliability,mobility flexibility,and obstacle crossing performance,a corresponding mechanical model was established and the robot wall adsorption mechanical analysis was performed;the adsorption unit was reasonably designed,the magnetic circuit of the adsorption unit was improved,the magnetic adsorption force of the robot was simulated,and the adsorption force experiment was performed.3.Based on the requirements of accurate weld detection,the PID principle and fuzzy PID control theory were analyzed.The fuzzy PID control strategy was used to improve the straightness accuracy of the robot walking on the wall.Based on precise control of robot movement,RS485 protocol was used;the control unit,drive motor,pressure sensor,serial relay control card and other hardware were reasonably selected,and the system hardware architecture was built;hardware was controlled and circuit was designed;program was wrote and robot workflow was designed.4.The experiments of robot’s crawling up and down vertically,moving horizontally,turning,and crossing obstacles on vertical walls were carried out.The magnetic particle inspection performance of the robot was evaluated,the imaging clarity of the camera was observed,and the entire workflow of the robot was tested.