Measurement And Reconstruction Of Pipeline Inwall Based On Laser Displacement Sensor

As a typical pipe,during the usage of artillery,the barrel bore is subjected to the burn corrosion of the gas,as well as the impact and wear of the projectile,resulting in defects,which reduces the striking precision and the safety usage of gun.Therefore,the detection of gun barrel,especially the depth information,is particularly important.Commonly used gun barrel inspection methods,such as projection method and CCD method,depend on the accuracy of image processing.At the same time,these methods have the problems of camera calibration accuracy,quantitative analysis difficulty,low-level automation,the axial dependence on the long push-pull mechanism,long gun barrel detection inconvenience,and the problem of eccentric error caused by self weight.Therefore,it is a very crutial to present a measurement system with high precision,which can quantitatively describe the overall situation and defect information of the barrel bore,and make the detection process more automatic.In this paper,we propose a barrel bore detection system based on laser displacement sensor.Firstly,we collect the depth information of barrel bore directly,combine with rotary motor speed,scanning frequency,motor speed,and 3D reconstruction of the barrel bore,to obtain the 3D coordinates of the barrel bore points in the barrel coordinate system,and present both the 2D and 3D visible results of the barrel bore reconstruction.Secondly,we quantitatively analyze parameters such as bore diameter,defect size and location,as well as gun barrel axes.We also propose a detection scheme and correction algorithm for detecting the eccentricity error of the measuring car.Finally,we design the data processing program and user interface for this system.The experiments show that our system has advantage in high-precision quantitative detection of the barrel bore,and prove the validity of our mathematical model for barrel bore reconstruction.The main research work,innovation and results are as follows.1.A 45-degree mirror turning path ranging method is proposed,and the barrel bore diameter measurement process is optimized.The barrel bore scanning parameters are designed.The circumferential positioning accuracy of the 120 mm caliber can reach 0.018 degree,and the circumferential maximum resolution is 0.02 mm.2.The measurement of the tube wall distance and the software and hardware design & debug of the data acquisition system are fulfilled.Inlcuding: The design of the laser probe light path and scan parameter,the structure design and main components selection of measuring car and crawler,the design and debugging of the data acquisition system circuit,the design and debugging of the data acquisition system software,serial initialization software,and upper computer control software.3.The mathematical model of data processing and 3D reconstruction of gun barrel is presented,and the parameters of barrel bore are quantitatively obtained.Experiment environment setup,function debugging of each module are also completed.The data processing program of the acquisition signal and the MATLAB GUI interface of the tube wall 3D reconstruction system are compiled.The visual results of barrel bore 3D reconstruction and 2D expansion are shown,and the feasibility of the model is verified by experiments.The experimental results show that the maximum error of the defect measurement is 0.7141 mm,and the accuracy of the diameter measurement is 0.318% for the measured pipeline.4.A correction model for measuring the position and pose errors of measuring car based on PSD is designed,and the influence of different angles and pose errors on measurement errors is given qualitatively and quantitatively.