ABSTRACT
Vehicles travelling at variable speed over irregular guide-ways are generally investigated by a nonstationary stochastic analysis. Up to now the variances of the vehicle response are gained from a matrix differential equation. In this paper a modification of the excitation process description is proposed which yields a substantial simplification: The resulting covariance analysis can be reduced to the solution of linear algebraic matrix equations which are solved by transformation techniques. An example demonstrates the application, the quality, and the advantages of the developed approximation method compared with the conventional exact analysis. The formulation holds for linear time-invariant multi-axle vehicle systems of arbitrary order with coloured noise excitation.
