TrainDy software

TrainDy is a UIC-approved software program that calculates longitudinal forces along trains.
A key feature of TrainDy software is its capacity to solve both pneumatic problems (venting of brake pipe and filling of brake cylinders) and mechanical problems (computation of relative movement between consecutive wagons). This feature makes TrainDy particularly useful for studying new freight trainset compositions.
TrainDy can be used to:

  • analyse train failures (derailment, disruptions, etc.)
  • understand the influence of technical parameters or operating conditions
  • optimise train productivity (increasing train mass or length, defining new driving rules for trains or design rules for rolling stock)

TrainDy software is managed and developed in Matlab (international standard programming language) by the UIC TrainDy Special Group.

TrainDy Special Group

The current members of the TrainDy Special Group are:

Operators/Industry: Faiveley Transport (a Wabtec Company), Knorr Bremse SfS mbH

Research Institutes: RAILENIUM, TUBITAK RUTE

Universities: University of Rome Tor Vergata, Technical University of Berlin, University Antonio de Nebrijia


The objectives of the special group are to keep the TrainDy software up to date and to increase its membership in order to maximise use of TrainDy among freight operators and deliver services to customers interested in productivity gains.

TrainDy+ feasibility study

In 2021 UIC launched “TrainDy+ how to simulate tomorrow’s freight trains - feasibility study” (P706).
The objective of this feasibility study was to examine how to achieve the objectives set by the sector by improving the TrainDy software, taking into account the time, costs and steps required for each objective.

The following possibilities of development have been analysed in the TrainDy+ final document:

  • Wagon order optimisation
  • Electro-pneumatic brake
  • Energy optimisation
  • Integration of wheel/rail contact in longitudinal train dynamics
  • Automatic statistical computation
  • Simulator for Autonomous Trains
  • Digital automatic coupling

The results of the Project 706 are available on UIC ETF shop:

TrainDy+, how to simulate tomorrow freight trains: feasibility study
November 2021

View on

Revision of UIC Leaflet 421: IRS 40421

In the framework of the UIC Project 496, UIC Leaflet 421 “Rules for the consist and braking of international freight trains” has been updated and migrated into IRS 40421.

IRS 40421 allows train compositions exceeding the length/mass limits if longitudinal forces are assessed with multibody dynamic software such as TrainDy, and describes a statistical method for generation of random trains in accordance with technical and operational parameters such as wagon type, train mass (or length), wagon payload, etc. However, TrainDy did not have a tool to generate random trains taking into account varying technical parameters. to overcome this a statistical tool was developed by the University of Rome Tor Vergata and has been validated by the TrainDy Special Group.

IRS 40421 content is also the result of the study for the CEF-PSA UBS action project. The study has been carried out by SNCF as member of the Special Group TrainDy.
The results of the Project 496 and the report of the study for the CEF-PSA UBS action project are available on UIC ETF shop:

Long Trains project

Long Trains was a UIC project (P573) which, in cooperation with EU Shift2Rail, aimed to increase and optimise freight train tonnage/length using TrainDy software and the UIC Leaflet 421 methodology for generating random trains. The results for longitudinal compression forces are compared with reference trains (750 m – heavy load train in G) for the following coupled trains:

  • 750 m trains with two locomotives (long locomotive brake regime for the first train, GP for the second)
  • 1,050 m trains with two locomotives (long locomotive brake regime for the first train, GP for the second)
  • 1,500 m trains with four locomotives

The results of the Project 573 are available on UIC ETF shop:

The basic principle of Long Train project have been further developed by TrainDy members in the framework of the projects FR8RAIL II and Marathon2Operation, a Shift2Rail project coordinated by the University of Rome Tor Vergata.

Accessing TrainDy and/or service delivery

Membership of the UIC TrainDy consortium is required for access to TrainDy. The experts within the consortium are available to help interested parties to define their specific needs.

UIC contact

For more information, please contact the TrainDy Special Group


Share this