Research On Control System Of Superheater Pipe Inspection Robot And Pipe Diameter Inspection

Being one of the three significant components of thermal power plants,the safety of the boiler ensures the normal operation of the entire system,and more than half of the boiler’s heating and leakage accidents come from the boiler’s "four tubes".Superheater pipeline is the most common pipeline among the "four pipes",in order to ensure the stable and reliable operation of power plants,doing regular inspection to these pipes is evitable and necessary.The method of manually inspecting pipelines is not only time-consuming,labor-intensive,and not effective,but also dangerous.Therefore,this article combines the working conditions and inspection requirements of the boiler superheater pipeline in the power plant to design a robot executing superheater pipeline inspection,set up a global control programme,to determine the drive components according to the structure and control project.On the basis of the working conditions of the superheater pipeline inspection robot such as pipeline climbing,obstacle crossing and pipeline inspection,the motion mode and positioning process are analyzed respectively.The kinematics modeling of the robot body is performed using the D-H method,with the inverse solution obtained.Meanwhile,for the two gaits of the robot,fifth-degree polynomial interpolation is used to plan the trajectory of its joints.The main purpose of designing superheater pipeline inspection robot is to complete pipeline diameter inspection.Therefore,this article combines the actual working conditions and robot structure to analyze the advantages and disadvantages of common pipeline diameter noncontact measurement,and innovatively proposes a more suitable robot and engineering Diameter detection method of the pipeline.This method relies on a laser with a shape of "cross"intersecting in a circle to irradiate the pipe,taking the intersection of the laser pattern as the key point,solving the pipe diameter in combination with the spatial geometric relationship,and establishing a mathematical model.In order to locate the key points in the image,this paper proposes an image positioning method based on convolution kernel and threshold;at the same time,in order to convert the pixel coordinates of the key points in the image to the actual space size,this paper proposes Space circle radius measurement model and calibration method.Finally,the laser and CCD camera are used to realize the pipe diameter detection when the pipe axis is offset and rotated.In this paper,on the basis of the demands of each function of the superheater pipeline detection robot,the hardware circuit design based on the ARM microcontroller is completed,the underlying program of the lower computer microcontroller is built,and the control flow logic of the lower computer is designed,and the robot is designed based on this Host computer interface.In this paper,the dSPACE semi-physical simulator is used to build an experimental platform for pipeline diameter detection,and the diameter detection of pipelines of different materials,diameters at different distances,offsets,and inclination angles is completed in a simulated working condition.In this essay,I propose a method to improve the diameter detection accuracy to confirm the generality and accuracy of the pipeline diameter detection method proposed in this paper,and finally analyze the source of error based on the experimental data.