Study On Stability Of Friction Coefficient Of Rail Top Friction Control Agent Based On Curve Similarity

Friction control technology is one of the important means to reduce the wear of line rails and reduce railway maintenance and operating costs.In the friction control technology,the preparation of the rail top friction control agent is the core and difficulty of the problem.The key to the rail top friction control is to control the friction coefficient applied to the rail top friction control agent in the range of 0.3 to 0.45.When the friction coefficient is less than 0.3,derailment is easy to occur;and when the friction coefficient is greater than 0.45,the energy consumption of the train and the wear of the rail will increase greatly.In this paper,the stability of the friction coefficient of the rail top friction control agent is studied,and the stability judgment method of the friction coefficient of the rail top friction control agent based on the curve similarity discrimination is established.Based on the constructed quantitative method,the friction control agent for the rail top is controlled.Process stability and formulation component stability are investigated.The main work and innovations of the paper include:(1)A discrete curve continuous method and a new algorithm based on Hausdorff distance curve similarity judgment are proposed.The measured friction coefficients are all discrete curves,and the curvature calculation errors corresponding to the feature points are large.In this paper,the gene expression programming algorithm is used to make the discrete curves continuous,optimize the relevant parameters,obtain the curvature of the feature points.The Hausdorff distance is used to measure the distance between the reference curve and the curve to be judged,then the signature data is used to test,and the eight-dimensional feature data is obtained,the dimension of the curve is reduced by the Manhattan distance weighted summation,and finally the lower equal error rate is obtained.The new algorithm lays the foundation for the quantitative study of the stability of the rail top friction control agent.(2)For the rail top friction control,the design meets the required formula,and the relationship between the friction coefficient and time is obtained through experiments.According to the performance control strategy of the rail top friction material,the design principle of the control agent and the proportion of the composition formula,the stability of the process and composition formula of the friction control agent is analyzed from the qualitative point of view,and the experimental results of the friction coefficient test are evaluated.By testing the stability of the friction control agent process and the composition formula,the stability discrimination method of the experimental curve with the comparison of the reference curve and the stability of the experimental curve without the reference curve is constructed.A method for judging the stability of friction coefficient of rail-top friction control agent based on curve similarity is proposed.(3)For the experimental curve with the reference curve comparison,the Hausdorff distance metric method of the feature point curvature is used for analysis.The experimental results show that different operating environments,such as temperature and pressure changes,have little effect on the stability of the friction control agent,the process has strong stability;the slight difference in the formulation ratio has little effect on the stability of the friction control agent,indicating that the formulation also has strong stability.For the experimental curve without the reference curve comparison,the experimental discrete data is continuated by GEP,and the area method is used for measurement.The experimental results show that the fitness function values of the process experiment curve and the formula experiment curve are at a low level.Since the qualitative stability evaluation results are consistent with the quantitative experimental results,the field test results also show that the curve similarity discrimination method is suitable for the stability evaluation of the rail top friction control agent.In this paper,mathematical methods are used to find the optimal design scheme for safe operation of products,a discrete space curve similarity discrimination algorithm based on Hausdorff distance is presented.GEP is introduced to make discrete data continuous,and the friction coefficient stability of the rail top friction control agent is studied to solve the problem of rail top friction control.