The railway multibody software developed for more than 20 years by INRETS (now IFSTTAR) under the name VOCO®, has been dedicated from the origin to highly non linear elements, such as the dry friction dampers of freight bogies and the wheel rail contact based on measured profiles. A second important step has been the discovery of a particular method in order to simulate on sinuous tracks. In the aim of industrial applications, the specification has always been to reach the goal of real time. Although it is not possible in all the cases, the recent nonhertzian contact development is allowing real-time simulation to be achieved.