Design And Implementation Of The Rail Corrugation Wide-area Measurement System

In recent decades,with the maturing and popularization of high-speed railway technology,regular trains are gradually replaced by high-speed trains,with the improvement of the train speed,the requirements for the smoothness of the track are more and more stringent.Especially the irregularity caused by the rail corrugation on the top of the rail,hence,the schedule maintenance are very necessary for rail corrugation.Today,static measurement and dynamic measurement are commonly used to measure the rail corrugation,because the static way is slow,subjective,and dangerous and is limited by the dimension,compared with static measurement,dynamic measurement is more efficient,more flexible and safer.So the rail corrugation dynamic measurement techniques are critical to guarantee transport security and rail maintenance.In this thesis,the Traditional chord-based method are analyzed and introduced,and it is pointed out that the chord-based method is the basic measurement method of rail corrugation.The theoretical basis and performance of the Two-point verse sine method and Three-point verse sine method are analyzed in detail,and it is known that the effective measuring waveband of each single-chord model is limited that they can not cover the wanted broadband from 30 mm to 60 m.Therefore,in the view of the problems that exist in Traditional chord-based method,this thesis proposed a wide-area measurement method,and gives the basic flow of wide-area measurement method.And it can be referred to as combined string method considered from the structure.On the one hand,through the flexible combination of 3 detecting points,combined with the advantages of long wave recovery that based two-point chord and short wave recovery that based three-point asymmetrical chord together.Wide-area measurement of the orbit can be realized on the same platform without increasing the cost.On the other hand,the design of inverse filter with least square method instead frequency sampling,it is not only used to compute the amplitude-frequency characteristic of the transfer function on the half symmetry interval,but also eliminates the calculation of phase-frequency characteristic and simplifies the design difficulty.So that the whole design process is more concise and convenient.After that,according to the flow and requirements of wide-area measurement method,the design goal of the wide-area measurement system of the rail corrugation is given,the hardware part and the software part are designed in detail,the whole wide-areameasurement platform is built in the hardware part,and the flow of the the wide-area measurement of rail corrugation is given in the software part.Finally,in the simulation environment and the measured environment,the wide-area measurement method and the wide-area measurement system are respectively implemented and the precision verification,the experimental results showed that the wide-area measurement system could measure the wide-area rail corrugation precisely in the condition of no increase in cost.It has the definite theoretical and engineering application value.