This paper on "Re-Using CAD Geometry in CAE" was presented at the NAFEMS World Congress on The Evolution of Product Simulation From Established Methods to Virtual Testing & Prototyping - 24-28 April 2001, The Grand Hotel, Lake Como, Italy.

Abstract

The need to re-use CAD geometry downstream, in CAE, escalates. But it is now widely recognised that geometry data exchange is a huge resource sink for engineering analysts. There are many articles, many products and many claims. Yet the problem only seems to get worse.
Poor old IGES has taken a lot of flack. STEP has long glinted over the horizon, but sadly there is now talk of having to flavour this deeply thought out 'standard'. And now we have OMG coming into view, not to mention Djinn.
Paper drawings have still not gone away. Electronic drawings continue to be widely relied on. We are told that 3D modelling is where it should all be at, and yes, 3D modelling is taking over: having reached the magic 5% take-up inflection point in 1999 according to technology watcher Joel Orr.
So as the 3D modelling revolution sweeps in, does it bring a solution to the interoperability problem?
According to some solid modelling kernel providers, it should. But the goal of painless model exchange between CAD and CAE systems remains elusive. Designs, paper or electronic, have bugs. CAx software has bugs and hence models have bugs. CAx and CAy interpret differently. Exchange media carry representational differences, even in native forms. So we have semantic, syntactic and lexical problem territories. Automatic data translators can be readily demonstrated to solve some problems, but the cases that fail tend to be expensive: a reliable interoperability process needs more. Certainly, 3D solid modelling offers little inherent balm. This deep seated and multi-facetted problem needs an innovative strategy.
This paper attempts to bring some insight into why 3D modelling seems to aggravate rather than solve the problem of re-using CAD geometry in CAE, and advocates a strategy to ease the pain.