Model Based Measurement of Railway Track Irregularities

Knowledge of track irregularities is highly important for the railway system. The established measuring methods need special measuring vehicles or other complex and expensive measuring tools. According to the measuring method presented in this paper track irregularities are calculated with the help of the car body acceleration measured on the rail vehicle. The calculation proceeds on the basis of the well-known and verified multibody model of a rail vehicle. The range of measurement devices is reduced to two acceleration measurement points in the driver's cab of a vehicle. The initial part of the present article elucidates the idea of the measuring method. Then, the example of a single-mass oscillator with, first, two independent and, finally, two correlated excitations shows how the measuring method can be applied to rail vehicles. Results are illustrated with a two-dimensional total vehicle model.