Research On Intelligent Detecting System Of Mechanical Pointer Pressure Gauge

The mechanical pointer pressure gauge is widely used in industrial production equipment and system,in order to ensure its stable and reliable measurement accuracy,it needs to be tested regularly.In the field of pressure measurement and detection,pointer pressure gauge has a large amount of inspection,and its types and specifications are different.The traditional pointer pressure gauge detection method has low detection accuracy and low working efficiency.In addition,the detection process and detection data cannot be automatically recorded and retrospectively reviewed.Therefore,using intelligent detection system to efficiently complete the pressure gauge detection work is the pursuit of the goal of this subject,but also the expectation of many measurement detection units.This topic is aimed at the actual demand of the Institute of Metrology,research and development of a set of pointer pressure gauge for the intelligent detection system.By means of model design,algorithm derivation,simulation analysis and test verification,the identification algorithm of pointer indicator of pressure gauge and quick connector of threaded joint are studied deeply.The main research contents and achievements are as follows:(1)Overall scheme design and physical construction of detection system.According to the working condition analysis and functional requirements of the detection system,the structure composition,working principle and workflow of the detection system are clarified.According to the characteristics of pressure gauge and working distance and other factors,the light source and image acquisition device are selected,and the lighting mode is determined to complete the construction of machine vision system.Modular design of the mechanical structure of the detection system,the use of Solid Works software on the overall framework of the detection system,the standard pressure source and threaded joint fast connector for 3D modeling.Finally,a physical device of the detection system was built to verify the test.The results show that the identification accuracy and speed of the indicator of the pressure gauge,the pressure loading speed and the overall sealing performance of the detection system all meet the design requirements.(2)Research and improvement on identification algorithm of pointer indicator of pointer pressure gauge.According to the test in the process of acquisition of pressure gauge image characteristics,puts forward a dial center extraction algorithm based on the intersection of pointer and pointer type pressure gauge pointer based on this algorithm in several identification methods,in-depth study of the method steps including image preprocessing,dial center extraction,the scale line identification,pointer axis equation of the straight line fitting and Angle ratio method to calculate the pointer readings.This algorithm is implemented based on VS2019 and Open CV4.0,and compared with the mature dial center extraction algorithm,the experimental results show that the accuracy,speed and precision of the final pointer display calculation of the proposed algorithm have been significantly improved.The algorithm was improved to improve the robustness of the algorithm because the indicator of pressure gauge could not be accurately identified in the conditions of pointer occlusion,damping fluid refraction and scale adhesion.At the same time,error analysis and compensation correction of the algorithm are carried out according to the experimental results.(3)Reliability research and Structure optimization of fast connector with threaded joint.The structure and sealing reliability of the threaded quick connector are simulated by ANSYS software.During the analysis,it is found that there is a negative correlation between the sealing performance and the deformation of the threaded piece in the flap.Latin square test design,response surface model prediction and multi-objective genetic algorithm are used to optimize the structure of the internal thread segment,and the structural deformation is reduced.The optimized structure mass increases slightly by 6.16%,the maximum deformation decreases by 35.75%,and the maximum stress decreases by 29.7%.The threaded quick connector is made and its sealing performance is verified by test.The results show that the optimized threaded quick connector meets the design requirements of verification system.