Research On Detection And Characterization Of Surface Damage Of Electrical Contact In Current Carrying Track

The electrical contact of the current carrying rails is an important component in many modern automatic equipment.Its health will directly affect the operation of the equipment and industrial production efficiency,and the damage to the surface of the slide rail is the main factor affecting the health of electrical contact.During the operation of the equipment,the surface of the guide rail often suffers extremely small damage under the action of the friction of the electrical contact.After the accumulation of the damage,the damage will gradually expand,which will cause the equipment to fail.When the fault is more serious,it may even threaten personal safety and cause irreparable economic losses.Therefore,it is extremely important to judge whether the surface of the electrical contact rail has minor damage in time and determine the specific situation of the damage.In this paper,the electric contact current-carrying track is taken as the research object,and focuses on the research of on-line monitoring of small damage on the surface of the guide rail and offline quantitative analysis of the small damage to judge the overall health of the guide rail.Aiming at the problem that it is difficult to identify the minor damage on the surface of the electrical contact rail,this paper proposes a method based on the vibration signal analysis of the rail.As the vibration signal of the guide rail is extremely weak,it is difficult to detect damage.Based on the summary and analysis of structural health monitoring at home and abroad,a set of guide rail vibration signal analysis system is studied.First,accurately obtain the vibration signal on the guide rail surface,and then use the modified ensemble empirical mode decomposition(MEEMD)to perform noise reduction on the vibration signal,and then use the multi-scale permutation entropy(MPE)method to analyze and sort the denoised data.Finally,judge whether the guide rail is damaged according to the change of the MPE value.In order to realize the quantitative analysis of the minor damage on the guide rail surface,a method based on 3D point cloud data analysis of the guide rail surface was studied offline.First of all,in order to solve the problem of the low accuracy of detecting the small damage on the guide rail surface,a damage region extraction method based onthe combination of the chord angle method and the perimeter method was proposed to obtain the point cloud data of the guide rail damage.Then,in order to accurately obtain the boundary of the damage area,a two-way nearest point search method is proposed to obtain the damage surface morphology of the guide rail.Finally,in order to quantitatively analyze the minor damage of the guide rail,a method combining a point cloud partition and a deterministic area calculation model method was proposed to calculate the damage parameters(damage volume,mass,area,etc.)of the guide rail,and provide a basis for the health evaluation of the guide rail.In order to verify the accuracy of the proposed method,a three-dimensional information acquisition system for the current-carrying rail electrical contact tester and the surface of the guide rail can be designed to simulate the real working environment,which provides a reliable basis for the study of guide rail damage.The experimental results show that the on-line identification method of track damage based on vibration analysis can accurately determine whether there is minor damage to the guide rail;The off-line track damage measurement method based on point cloud data analysis can accurately extract the damage morphology of the rail surface and accurately calculate the overall damage characteristics of the damaged area,which provides a reliable reference for the surface research of current-carrying track electric contact.