Pro/ENGINEER 2001

In June 2001 TechniCom journeyed to PTC's new headquarters in Needham, MA to view the latest release of Pro/ENGINEER - 2001. We had the opportunity to meet with key product management involved with Pro/ENGINEER, Granite, and ProjectLink.

Pro/ENGINEER 2001

A number of innovative changes improve the ease of use of Pro/E 2001, which shipped to the masses earlier this month. These include click and drag for rounds, extrusion depth, and revolve angles used in features. Feature agility has been improved - inheritance from features allow for process variants; a streamlined UI has fewer picks and an improved workflow; a graphical comparison of models helps compares two models (see image 28.5); and an interactive surface design extension (ISDX) provides impressive surfacing within Pro/E (costing only $3995 plus the ASX extension). Most impressive is the improvement of behavioral modeling by allowing the persistence of behaviors by storing optimization as a feature.

To get a feeling for the improvements in Pro/E 2001 we viewed a demonstration of the modification required to a wheel on the "world car", a project that PTC funded and completed, requiring 3 design teams simultaneously developing a world racing car in less than 7 days. The first fourteen images here depict the changes being made during this discussion.

We were able to view all of the components of the automobile using a shrink wrap representation, and were easily able to rotate and the spin the entire model to view it. The entire model contains more then 2500 parts. By selecting the wheel from within this simplified assembly structure, the wheel opened up with its detailed Pro/ENGINEER history, including all features. Our objective is to change the spokes on the wheel and the wheel hub to become more stylish. During this process we investigated whether there was any interference between the wheel and other pre- selected components. In this case, the component were interested in was a brake caliber. By visual inspection we observed that the brake caliber was interfering with one of the spokes. Putting the interference problem aside until later, we decided to modify the spokes to the new design. Interestingly, many of Pro/E 's new commands do not require menu selections - once we selected the spoke, the right mouse button and opened a relatively short menu. One of the options on this menu was "modify." When we selected "modify," the parameter controlling the number of spokes was simply changed the number from 6 to 5. To develop the new spoke design, we changed the geometry definition for the spoke by manipulating the curves generating the spokes surface and its interaction with the wheel. The spoke was defined as a style feature, a new feature delivered with interactive surface design (ISDX). This Style Feature is new for 2001.

Using Direct Modeling we were able to push and pull on the curves and the surface geometry to capture the same exact design that we were looking for. During the process we were also manipulating the curves on the spoke to avoid the interference with the brake caliber that we detected previously. Take a look at images 9, 10, and 11. Note that after making the change, the behavior of the wheel changed and we were now automatically notified not only that it was unbalanced, but why -- very nice!

We also modified the hexagonal extrusion of the wheel hub for the purpose of changing just the shape - not any structural changes. We deleted the section that drove the feature and built a new section. When we were happy with the new cross section, the new feature recalculated itself. BUT, the new extruded solid kept the draft angle and rounds that were originally the children of the extrusion. See images 14 through 19. We do not believe that this is possible in any other system. Somehow, Pro/E 2001 was smart enough to transfer the parent from the old extrusion to the new one, even with the topology change of the hex to the star shape. The star inherited all of the rounds and draft angles associated with the original hexagonal shape. Intent referencing was actually introduced in an earlier release, but is well integrated in this version. During this brief demo the instances of design changes for which this inheritance would work and where it would not. We hope to clarify this with PTC and will report on it in a later issue.

Next, we ran ModelCHECK. ModelCHECK automatically compared this part to other parts of similar geometric shape and indicated that we were missing a few other items that we needed on the model before it would be allowed to check in. By knowing which other models had similar geometry, we were able to find features on another model which we needed to mount the wheel onto the chassis. We were able to copy and paste this group of features into the new design by selecting a cylinder which this group of features would automatically attach itself to. Images 20 through 26 depict the sequence. This combination of ModelCHECK and feature inheritance allowed us to easily add a complex set of features into our design, saving lots of design time.

The next step was to check that the center of gravity of the new design was at the center of gravity that was previously specified in order to correctly meet the suspension requirements. We activated behavior modeling. The objective that had been predefined was - a zero distance between the two centers of gravity. To bring the wheel back into alignment, the system had previously defined three parameters that were allowed to be changed. These included a balancing ribs diameter and thickness and the thickness of a rear plate. In just a few minutes, ProE's behavioral modeling had correctly altered the model so that the CG's were concurrent. This optimization could also be included as a feature so that it would be automatically included when the model was regenerated. Images 28 through 30 depict this sequence.

Design models are fine, but the real power of modeling is making downstream applications, such as manufacturing, easier. Pro/ENGINEER 2001 insures that downstream models are easily connected to design models by using associative derived models. A derived model uses uses inherited features from the primary model to create a one way associative model. Here is how it worked for us. We opened the derived model which was connected to the design model upon which we had been working. After regeneration, we observed that the changes that we had made were brought into the new derived model. Some of the features were missing, as planned, because they had been removed when the derived model was built. This included the features and rounds on the front hub. See image 31. A surface model comparison between the two derived models returned the results in less than a minute, and allowed us to see precisely the surfaces that were deleted or changed. We also had the opportunity to suppress additional features that we had already added to the model so that we could use the derived model more effectively. We are also able to make local changes to this derived model. Since it's was associative, it preserves the original design model. The utility of something like this would be in a readily apparent for a casting, which might have many fewer features which are later machined to make the final finished model.

All in all we were quite impressed with the progress made in Pro/ENGINEER 2001! PTC's very unique behavioral modeling continues to evolve, making its capabilities easier to use and incorporate directly into the design process. The ease of use has been improved tremendously, not only because of the UI, but also with the integration of surfacing, feature inheritance, and derived models. Very large models also are much more easily manipulated due to the evolving use of shrink wrap. Bringing all this together with PTC's breadth of applications signals a real re-awakening of the technology advances we used to get from PTC! CAD designers should be most pleased with this release.

Granite and Windchill ProjectLink will be discussed in the next issue.

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