TASverter: a converter for space thermal model and data exchange


Duncan Gibson, ESTEC/ESA

Thermal Analysis, ESTEC/ESA

Note: TASverter is NOT a converter for STEP files from CAD!


In 1994, ESA initiated a study into what is still one of the biggest problems facing the space thermal analysis community: the need for reliable data transfer between different analysis tools. The outcome of that study was the start of the journey that would lead to the development of STEP-TAS and TASverter.

ESA sees STEP-TAS as the key technology for the harmonisation of space thermal analysis tools and data exchange between national agencies and industrial groups using different tools.

TASverter is a general converter for models used in Thermal Analysis for Space. It has “reader” modules for converting information from the native file formats of a number of [space] thermal analysis tools into a internal data structures, and “writer” modules to convert from these data structures into the native file formats of a number of [space] thermal analysis tools. The internal data structures are based directly on the STEP-TAS protocol.

TASverter was developed to replace some older tool-to-tool converters that involved a lot of duplicated code and were difficult to maintain.

TASverter became a cutting-edge technology demonstrator to show the reality of model data conversion and exchange using STEP-TAS. TASverter has been used extensively within ESA to verify and validate the development on the underlying STEP-TAS protocol using real-world models written for different thermal analysis tools. TASverter paved the way for the implementation of STEP-TAS interfaces in the commercial space thermal analysis tools.

The ultimate goal of the TASverter and STEP-TAS development was to create a tool independent standard for data exchange, and to transfer the interface software and lessons learned to the analysis tool vendors themselves. STEP-TAS interfaces are now available in some of the space thermal analysis tools, such as ESATAN-TMS and THERMICA.

Terms and Conditions

TASverter is provided free of charge by ESA, subject to the copyright and disclaimer at the bottom of this page. The latest version of the executables can be downloaded by clicking on the entry in the table below. Although you do not need to request a username and password to be able to download TASverter, you will be asked to provide your name and a valid e-mail address to which further download instructions will be sent.


The TASverter-2022 release introduces some new or updated functionality and continues to build on the improvements made in the 2019, 2017 and 2013 releases:

  • a new simple, experimental, Excel reader, with examples and template;
  • a redesigned STEP-TAS geometry viewer that runs directly in the user’s browser and that also creates an html file which can be shared with a customer or other team members;
  • a redesigned TASverterGUI that separates GMM and TMM conversions;
  • an extended User Manual that can also be opened in the user’s browser, and which contains improved documentation on conversion workflows, and refers to STEP-TAS interfaces in other thermal tools;
  • updates and bug-fixes to the TRASYS interface and to the “TMMverter” for converting between ESATAN-TMS and SINDA/Fluint thermal network models;
  • an update from the now-deprecated Python-2 to Python-3 and tkinter to allow continued working on more modern Linux and Windows-10 systems;

The STEP-TAS files produced by TASverter-2022, 2019, 2017 and 2013 all use the STEP-TAS v6 protocol and any STEP-TAS files should be compatible.

The TASverter development team has easy access to systems running Windows 10 and CentOS Linux, and has a large test suite for verifying that TASverter runs correctly on those systems, but can’t guarantee that TASverter-2022 will run correctly on other Windows and Linux platforms.

Thermal Desktop

In addition to TASverter, a new set of standalone converters for Thermal Desktop is also provided in the download list below.
Since the 6.1 release of Thermal Desktop (May 2019) a new API has facilitated these conversions.
The single zip file contains converters from STEP-TAS to Thermal Desktop and from Thermal Desktop to STEP-TAS. The zip file also includes usage instructions.

The Thermal Desktop converters have been tested on Windows 10 using a large number of new test cases and real models.
Nonetheless, they remain beta versions until more extensive testing is complete.
Eventually these converters may be merged into TASverter.


We are currently experiencing problems with the automated download, so requests have to be processed manually. This means that you should receive an additional e-mail notification with the download link within 1 to 7 days.
If you do not receive feedback after that time, please send an e-mail to stating your name, occupation and organisation, and we will contact you as soon as possible.

TASverter r2022-12-20

System Filename Size Link
Windows 10 TASverter-r2022-12-20-Win10.zip 16 Mb Download
Linux TASverter-r2022-12-20-Linux.tgz 17 Mb Download
all Release Notes r2022-12-20 View
all User Manual r2022-12-20 View
all Frequently Asked Questions r2022-12-20 View

For older versions, please visit the TASverter archive page.

Thermal Desktop converters

System Filename Size
Windows 10 td_tas_converters_beta_2020-09-15.zip 8 Mb Download
Windows 10 td_tas_converters_beta_2019-08-09.zip 7 Mb Download

Copyright © 2003-2023 European Space Agency


Warranty and Disclaimer of Warranty.  Although every attempt has been made
to ensure the correctness of this converter, it is provided "AS IS" and WITHOUT
WARRANTY, either express or implied, including, without limitation, the

Limitation of Liability. Under no circumstances and under no legal theory,
whether in tort (including negligence), contract, or otherwise, shall the provider
be liable to any person for any direct, indirect, special, incidental, or
consequential damages of any character arising as a result of the use of this
converter including, without limitation, damages for loss of goodwill, work
stoppage, computer failure or malfunction, or any and all other commercial
damages or losses.
It is not permitted to redistribute this software without the express written
permission of the European Space Agency.