1. Creo 1.0 Major Issue Flex Modeling and Drawing Associativity
TE Connectivity Use Case
May 12, 2018

2. Synopsis
Since Pro/Engineer’s inception, model to drawing bi-directional associativity has always been one of the major benefits. In a drawing-centric environment such as what we have here at TE, the fact that a designer did not have to ensure that the drawing geometry was correct since it was an exact representation of the model has allowed designers to focus their efforts on geometry creation in the model and annotating the design in the drawing.
With the introduction of Flexible Modeling in Creo 1.0, a major change to the 3D modeling paradigm has been introduced which has the potential to greatly improve the modeling process. However, a major issue has been discovered whereas if Flexible Modeling tools are used to make changes to a 3D model, dimensions in the 2D drawing do not update to reflect the geometry changes that resulted from the Flexible Modeling features. The result is that the dimension values are incorrect. If the geometry modifications are subtle, the incorrect dimension values could likely never be realized and could potentially result in costly tooling changes after tooling has been built and the discrepancy is discovered.
May 12, 2018

3. Use Case Increasing The Beam Length on Stamped Contact
The majority of the connectors designed and manufactured at TE include a stamped contact that includes a beam such as the one shown on the picture below. The length of this beam is one of a few attributes (parameters) that directly influences a key characteristic of the connector called “insertion force” (how much force is required to mate the male and female components of the connector system). In this use case, the designer needs to increase the beam length by .05 mm which is quite common.
May 12, 2018

4. Use Case Increasing The Beam Length on Stamped Contact
As a result of increasing the beam length by .05 mm, the 3 dimensions shown in red below should increase by .05 mm.
May 12, 2018

5. Use Case Increasing The Beam Length on Stamped Contact
There are multiple use cases for using either Flex Modeling or Creo Direct to increase the beam length. All of yield the same result shown on the next slide regarding the drawing dimensions.
The drawing was created using an imported model.
An engineer or designer used Creo Direct to increase the beam length
The original design intent made it difficult to change the beam length due to model regeneration failures.
May 12, 2018

6. Use Case Increasing The Beam Length on Stamped Contact
After increasing the beam length either by means of Flex Modeling in Creo Parametric or by using Creo Direct, the drawing dimensions shown in red do not update. This is true for both created and shown dimensions. The green dimensions have been added after the length has been increased to indicate what the values should be.
May 12, 2018

7. Conclusion
TE Connectivity firmly believes that drawing to model associativity is a fundamental requirement of Creo since it has always been one of the few major benefits of Pro/Engineer. The risk of introducing Flexible Modeling without this issue being resolved is too great due to the potential costs that could result from this fundamental failure in the bi-directional associative nature of PTC’s former CAD application Pro/Engineer. We are still a drawing-centric company and the 2D drawing viewables are still the document of record. As a global enterprise, the 2D drawing viewables often times are all that is provided to our tooling vendors for tool design and build. If these drawings include incorrect dimension values, the impact on our business would be too costly for us to accept.
May 12, 2018

8. Thank you!
May 12, 2018