In the railway high-speed lines exploitation arises some problems such as aerodynamic drag forces.

The circulation of trains at commercial speeds of up 300 km / h involves a number of difficulties in the field of aerodynamics. On the one hand the energy cost of a train traveling at 300 km / h, on the other hand, the interaction with the environment and the crossing with other trains running in opposite directions. Read more →

The TVM (Transmission Voie-Machine) is the protection system implemented in the French railway high-speed lines. This system presents in the driver cab the maximun speeds indications and speed restriction orders in every moment.

The TVM is the answer to the problem that occurs when driving at speeds above 220 km/h. This speed is the maximum considered that the indications and orders are displayed to the driver via semaphore signals, light signals or markers located on the track side.

Read more →