Mass Properties Exchange Format

Standardization Forum


To promote the development of an international standard for the electronic exchange of mass properties data.


The principal objective for this web page is to provide a forum for the exchange of ideas and information on the Mass Properties Exchange (MPEX) format. Near term objectives are to present the recommendations made for the proposed standard and to track its development status.

MPEX Paper (Original / Revised)

This technical paper presents the rational for creating a standard mass properties data format and gives baseline recommendations for the its implementation. The original paper was presented at the 1996 International Conference on Mass Properties Engineering sponsored by the Society of Allied Weight Engineers. A revised version of this paper was prepared for the 2001 International Conference. Please read it for the latest information on the MPEX format.


The original technical paper given above was presented in the Computer Applications session of the 1996 conference. The ideas and recommendations presented were well received and most in attendance agreed that developing such a standard would be a worth while endeavor for the SAWE to pursue. The author of the paper was asked to head a committee to pursue this goal.

This web page and its contains were presented at the 1997 International SAWE Conference. The members present gave there support of the approach. It was felt that the MPEX format could be covered by the Recommended Practice Policy established by the Society. The current specifications of the MPEX format have been assembled into the web page given below.

The recommendations given in the earlier paper have been unilaterally adopted in the current version of the MPEX format specifications. The paper was rewritten to comply with the format used for Recommended Practices. It was hoped that all members would have a chance to review this web page prior to the 1998 International SAWE Conference. However, due to its late posting (a few days before the conference), this is extremely unlikely. Members of our society were encourage to review its content prior to the 1999 conference.

In the past couple of years I've continue to refine the MPEX approach and have presented it at various SAWE regional and the international conferences but progress on getting an accepted standard has somewhat stagnated due to lack of interest. However, I continue to see the benefit of its use in applications that I've work with and still believe that we on the right path with respect to creating this standard.

I was not able to attend the international conference in June of 2001 because of some last minute matters that came up. I had intended to present the revised version of the paper at the conference. As part of the presentation I had hoped to incorporate a discussion on the relevance of XML to what we are working to accomplish. The eXtensible Markup Language is fast becoming the standard for exchanging information between computer applications and platforms. It is becoming apparent that mass properties should also be exposed to this approach. The work that has gone into creating the MPEX format to date has a sound design and will serve as the basis of things to come in the future. I encourage you to use it to exchange mass property data.

The MPEX format continues to be adopted by more organizations. One of them recently pointed out a problem in the documentation. This latest update corrects an error in the definition for the ENTRIES data set. The entry inertias are always given about the CG of the entry not about its origin as previously stated.

MPEX Format Specification (Review Edition - May 2005)

This web page gives the current version of the Recommended Practice for the MPEX format specification.  It is now ready for final reviews. Please review its contents and forward your comments and suggestions to Jerry Fleck (correct E-mail address by removing the X character).

This page maintained by Jerry Fleck
(Note: Correct E-mail address by removing the X character.)

Last Updated: May 2, 2008