Large IGS and STP files in SW 2005
Large IGS and STP files in SW 2005
(OP)
I recently received a giant (580 MB) file from a client in IGS format. I tried opening in in SW 2005 and it crashed my machine. My client then trimmed down the model (removed data I didn't need) and sent it in both IGS (240 MB) and STP (145 MB) format. I tried opening the smaller STP file, and got farther than before, but after about 20-30 minutes, the system is just frozen.
My system is as follows:
P4 3.2 Ghz
2 GB memory
Quadro FX 500 video
Win XP Pro SP2
Is my system just not able to handle files of this size? I have never had to deal with files this large before, so I am unsure if my hardware is just lacking, or if the issue may be elsewhere. Anyone have an idea of what specs my system would need in order to handle files this size?
Thanks!
My system is as follows:
P4 3.2 Ghz
2 GB memory
Quadro FX 500 video
Win XP Pro SP2
Is my system just not able to handle files of this size? I have never had to deal with files this large before, so I am unsure if my hardware is just lacking, or if the issue may be elsewhere. Anyone have an idea of what specs my system would need in order to handle files this size?
Thanks!






RE: Large IGS and STP files in SW 2005
Here is some information from an article I got from the web
Tolerance Strategies:
If the gaps between edges and faces become too large, solid-modeling programs can become confused about the boundaries of the model. The system can no longer distinguish the inside of a part from the universe around it. In such cases, the user might receive a message that the model is "corrupted." Consequently, all systems employ a strategy for computing the maximum allowable gap, or "tolerance zone," between an edge and the two faces it bounds. Unfortunately, different systems employ different strategies for computing this tolerance.
Pro/Engineer employs a variable tolerance model. The maximum gap is a fraction of the total model size. So for large models, such as jet engines, Pro/E allows larger gaps, while for small models, such as watch parts, only small gaps are permitted. The relative tolerance model is a clever one, and it enables Pro/E to run fast. Unfortunately, no other major CAD firms have adopted this strategy.
Most systems, including CATIA version four, Computervision's CADDS, and Spatial Technology's ACIS (employed by AutoCAD, Ashlar Vellum, IronCAD, SolidDesigner, and TurboCAD), employ a fixed tolerance model. The size of all gaps in all models is limited to the same default value. Most systems enable users to change this default value but the vendors strongly discourage such changes with scary disclaimers of what might happen to the CAD program's behavior.
The Parasolid kernel employed by Unigraphics, SolidWorks, Solid Edge, and Microstation employs a concept called "tolerant modeling." The tolerance is fixed, but larger gaps may be permitted on a face-by-face basis.
The difference in tolerance strategies causes problems when translating geometry from one system to another.
Models coming from Pro/Engineer or Unigraphics may have gaps that aren't acceptable to CATIA or SolidDesigner. The reverse is also true: Models from fixed tolerance systems may be unacceptable to Pro/E or UG if they contain gaps that are too large.
Low Accuracy:
Designers creating CAD models do not generally notice gaps between adjacent faces or between faces and their associated edge curves that exceed the allowable tolerance of their CAD programs. But such gaps can cause translations to fail and can stall NC, rapid prototyping, and finite-element applications.
There are a couple of ways that large gaps can creep into models. Because of its relative-tolerance strategy, Pro/Engineer can leave large gaps between large faces. ITI found one instance -- in an aircraft engine housing -- where a gap exceeded one millimeter.
Solid-modeling programs with fixed tolerances generally won't be able to sew up models with such large gaps. In these cases, translations simply fail, and it is up to the Pro/E user to tighten down the tolerance, regenerate the model, and try again.
Tolerant systems, such as those based on Parasolid, will sew models with large gaps. Large gaps also can be introduced into Parasolid models by importing surfaces. Surface-modeling programs -- such as Alias Studio or Pro/Designer, don't care about gaps between surfaces. Once incorporated into the solid, these large gaps can be passed through to STEP or IGES models or they can stall FEA, NC, and rapid prototyping programs. Or they can cause translations to programs such as AutoCAD or CATIA to fail.
Users of hybrid modeling systems can reduce accuracy errors by closing gaps between surfaces before importing them into solid-modeling programs. Most industrial designers don't have the patience for this type of work. Managers instead should hire cad-savvy technicians to check models before introducing them to engineering systems.
Best Regards,
Heckler
Sr. Mechanical Engineer
SW2005 SP 5.0 & Pro/E 2001
Dell Precision 370
P4 3.6 GHz, 1GB RAM
XP Pro SP2.0
NVIDIA Quadro FX 1400
o
_`\(,_
(_)/ (_)
Never argue with an idiot. They'll bring you down to their level and beat you with experience every time.
RE: Large IGS and STP files in SW 2005
If you can also add more RAM (borrowed from another machine?) that will also help greatly.
RE: Large IGS and STP files in SW 2005
RE: Large IGS and STP files in SW 2005
I'm not sure if you have to, but did you reboot after applying the switch.
BTW, SolidWorks can open native ProE files. I don't know how well SW05 translates, but SW06 did a good job with the files I imported.
RE: Large IGS and STP files in SW 2005
Here is some data that you might want to check with the originators of the pro/e data. Best of luck to you.
ENABLE_ABSOLUTE_ACCURACY - Yes
ACCURACY_LOWER_BOUND - value (between 1.0e-6 and 1.0e-4).
http://
http://www.proesite.com/accuracy.htm
Typically, a default relative accuracy of 0.0012 allows geometry to be calculated with a reasonable amount of computation and within a reasonable amount of time. Sometimes, however, specific model geometry may require that geometry calculations be sensitive to fine features or complex geometric shapes. Modification of accuracy for a model with this higher "level of detail" may be used as a last resort to assist Pro/ENGINEER in solving the model geometry.
Best Regards,
Heckler
Sr. Mechanical Engineer
SW2005 SP 5.0 & Pro/E 2001
Dell Precision 370
P4 3.6 GHz, 1GB RAM
XP Pro SP2.0
NVIDIA Quadro FX 1400
o
_`\(,_
(_)/ (_)
Never argue with an idiot. They'll bring you down to their level and beat you with experience every time.
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