Take hypothesis of wheel-rail rigid contact, this work presents a new method to characterize the vehicle-track interaction in the three-dimensional (3-D) space. The vehicle model is considered as a multi-rigid-body system with one car body, two bogie frames and four wheelsets that are connected by two-stage suspension systems. The track model is constructed by a versatile approach, where the finite elemental size and type of track components can be arbitrarily chosen and combined. The key matrices in depicting vehicle-track interaction are established with satisfaction of wheel-rail displacement complementarity by geometrical constraint equations and the wheel-rail force equilibrium by energy variational principle. Besides the functionality of depicting wheel-rail separations has been solved and compiled in the program. This model possesses the superiority of the previous models in computational stability. Besides the vehicle-track interaction at a 3-D space, which considers the wheel-rail contact geometries/creepages and infinite length calculation, are further formulated in the vehicle-track coupling matrices. Comparisons with general solutions built by well-known wheel-rail contact theories are conducted to show the engineering practicality of this model; moreover the differences of modelling results and the advancements of this model are also illustrated.