The C³I Recommendation defines a metadata model for simulation data (see main document, section 11), which is an evolution of the SimPDM metadata model published end of 2008. This data model was not designed to be a data exchange format, but as a formalized data scope definition. This made it possible to design the model with the flexibility needed to describe the required data structure independent from actual implementation methods and involved systems.

Consequently, the question came up, in how far existing data formats, which are either standardized or widely used in the industry, can be used to transfer the data in scope of the C³I recommendation. The motivation for the work described in this Annex was that such a mapping removes the need to define a data exchange format for the project group on the one hand, and the need to introduce this additional format and its associated interfaces into the IT landscape of the user companies on the other hand.

In this Annex, the wording “SimPDM metadata model” refers to the data model as defined in the ProSTEP iViP / VDA Recommendation “Integration of Simulation and Computation in a PDM Environment (SimPDM)”, published in 2008 as PSI 4 / VDA 4967, Annex E. The wording “C³I metadata model” refers to the evolved data model as defined in Annex A of the recommendation in hand.

To reach the aims described above, the following approach was taken:

First, a list of all applicable formats was collected and analyzed. The candidate formats were provided by the project group members. These were then compared to the SimPDM metadata model to see to what extend the investigated formats cover the SimPDM scope. The resulting table can be found in section 2.

Next, the target formats had to be selected from this initial list. The “Big Picture” shown in section 3 was used to position the various formats in relation to their respective domain. In the end, one format was selected for each of the three directions:

• SimPDM to PDM (SDM/PDM Synchronization)
• SimPDM to CAE (Data Management / Authoring Tool Integration)
• SimPDM to CAT

The criteria for the decision included:

• SimPDM scope coverage – the overlap should be as big as possible
• Standardization – a standardized target format would maintain neutrality of implementations from specific tools
• Propagation of use in industry – use of an established format removes the need to implement new interfaces
• Similarity of data model design philosophy – basic concepts should be transferrable

As result, the chosen formats are:

• SimPDM to PDM: Siemens PLMXML
• SimPDM to CAE: ISO 10303-209 (STEP AP209)
• SimPDM to CAT: ASAM ODS

The finally selected formats had to undergo a technical analysis, which showed in detail their similarities and differences compared to the SimPDM metadata model. The results are described in section 4.

Over the course of the C³I project, as a result of the work done on collaborative and CAD/CAE integration use cases as well as workflow and change management, the SimPDM metadata model was improved and extended, and thus evolved to become the C³I metadata model. Wherever changes had to be made, the selected target formats were polled to see if similar data structures already existed and could be incorporated.

As the final step, after work on the C³I data model was completed, a detailed mapping was defined from C³I to the selected data formats for PDM (Siemens PLMXML) and CAE (STEP AP 209). The intent of this unidirectional mapping is to show that in a scenario where PLMXML or AP209 is already used to transfer data, how these formats can be used to convey the information required in the C³I processes and use cases, i.e. in which data object of the target format to store the data as defined in the C³I metadata model. The mapping tables can be found in section 6.