Track irregularities estimation based on acceleration measurements

Track irregularity i s the main source of external excitation for a rolling stock system . And maintaining the alignment of railway track i s vitally important for the smooth and safe passage of railway vehicles. In this paper, a method for the identification of lateral and vertical track irregularity from acceleration measurements on board the train i s presented. The measurements for the track irregularities are the acceleration of the bogie and the car-body. The effectiveness of the proposed approach i s demonstrated by simulation results. The analysis of acceleration data in the time and frequency domain show that the displacement signals from bogies/car-body acceleration follow the lateral/vertical track irregularity very well. The track vertical irregularity have the most significant effect on the bogie vertical vibration, with high coherent value up to 0.95.While the car-body lateral vibration i s not closely related to the track lateral irregularity with low coherence values below 0.25.