Welcome to the Open Concurrent Design Tool (OCDT) Community Portal

OCDT is a client / server software package developed under a European Space Agency (ESA) contract to enable efficient multi-disciplinary concurrent engineering of space systems in the early life cycle phases.

OCDT implements a standard semantic data model defined in Annex A of the ECSS-E-TM-10-25 Technical Memorandum, titled System Engineering - Engineering Design Model Data Exchange (CDF).

The first implemented OCDT client is an easy-to-use add-in for Microsoft Excel® (versions 2010, 2013, 2016) that is integrated with Excel® to perform simple analysis and simulation. Other client tools for engineering analysis and simulation can also be integrated, through the use of OCDT adapters.

The OCDT server consists of a front-end web-services processor (using a REST API) and a back-end PostgreSQL database system for the persistent storage of OCDT shareable data. The server is able to support concurrent teams of more than 20 users and synchronising their engineering model content twice a minute or faster. Typically each user would represent a different domain of expertise (discipline).

The package is distributed under an ESA community open source software licence available for use and further development to users that qualify as a member of the OCDT Community.

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In order to gain access you need to qualify as a member of the OCDT Community. For this, you must be a person working for (or enrolled as student at) an organisation that legally resides in an ESA member state or cooperating state.

Please see What is ESA? on the main ESA website for the current list of eligible states.

To request an account, please send an e-mail to ocdt-support@esa.int with the following details:

  • first name
  • surname
  • affiliation
  • affiliation's web site URL
  • e-mail address

Note: You are required to provide a professional or educational e-mail address. Addresses at generic service providers like gmail.com, outlook.com, icloud.com, yahoo.com, etc. cannot be accepted for registration.