when constraints become invalid

[design-engine]

When assembly constraints become invalid, what can you do to fix the failure?

A - Modify the features in the failing component.
B - Modify the features in the other components.
C - Change constraints.
D - Suppress or freeze the failing component.
E - All of the above.


This is a strange question because a user could do all those things when trying to repair an invalid constraint. There is only one thing however that will fix the problem and thats change the constraints. What do you guys think is the correct answer?

I corrected several SAT questions in HS and still made under 1000


Edited by: design-engine

 

[Hatim]

I think the answer is "All of the above". Example: part A with 2 pins and part B with 2 holes. In assembling part A to B, 2 insert constraints used, one for each pin/hole pair. If the distance between the pins is not the same as the distance between the holes, invalid constraint encountered. We could modify part A or B or use a different constrain to avoid the invalid constraint status.

 

[design-engine]

Yes.... But 'change the constraints' would work EVERY time..... Maybe i over think these types of questions which is why I never do well on questions with multiple choice answers.

Thats how i define fix the failure. The other options would NOT always fix the failure. They might be used to fix a failure but not always.
Edited by: design-engine

 

[dgs]

Rather than asking what can you do, ask what should you do. Any of the answers are possible, but the question is why did it fail and what is the appropriate route to correct it givin the design perameters you are working under?

If one part was revised and the other part needs to a change to accommodate it, than A or B is appropriate.

If one part changed requiring a new assembly methodology, then C is appropriate.

However, it may be that the failure is a warning that the change made is not possible and should be reversed. To take Hatim's example, if the pin to pin distance in A is changed (perhaps inadvertantly), but changing B is not allowed (because, say, you already have 10,000 of B in stock), the assembly failure would tell the user that they've violated a design constraint and they need to rethink the change to A.

 

[Hatim]

I agree of course - no question about it. I guess that this type of questions is intended to be general, theoretical in some sense. The qustion writer, I think, doesn't want to test you on what should or should not be done, rather on what is the possible action.


By the way, I recently took a Pro/E test on ProveIt and I didn't score as I'd expect, though I'm already certified in teaching all PTC MCAD courses, because questions were misworded and used wrong terminology. After all, we never know who wrote those questions.

 

[design-engine]

it is a PTC certification question for the proe foundation test.

 

[dgs]

... 'change the constraints' would work EVERY time...

Not in the case that Hatim described., unless all you're after is dismissing the failure dialog. In that case, sure assemble it to the default and be done. Then it'll never fail. Might never be right, but it'll never fail.

BTW - Where does one find info on the PTC certification tests? Are they certification for teaching Pro|E or simply showing competence?

 

[design-engine]

for teaching pro/e....

all my ranting I have pissed off the ptc resellers so much (think of those poor solidoworks resellers) that PTC has asked us to teach both the PTC certified classes and our 'experience training'.

 

[design-engine]

Here is another question that stumps me. And i hate these types of questions.


True or False? A BOM Table is manually created. The user must type the names of all components used within the assembly.

True
False


Well we know the correct way to do the BOM is to use repeat regions.But that is not what the question states.The question is.... manually.yes.. if done manually the user would have to enter all the parts from the assembly.

 

[Hatim]

I agree that some of the questions (even those written by PTC gurus) are not very specific and leave some room for doubts, which makes a knowledgeable person taking a test obtain less-than-perfect score.

 

[design-engine]

Thanks Hatim,

somehow i feel better.

 

[kdem]

I don't know if this would be the way to think of it but my initial thought is False because setting up a BOM Table to me means you're setting the table to use BOM ballons. To use BOM ballons you need a repeat region and in the repeat region youtypereport parameter values.
Edited by: kdem

 

[rudresh.hm]

when u do not need a BOM table which is parametric, u need not always sit and enter all the index, part no, part name, bla, bla, bla....... manually!<?:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" />


U can create a table by repeat region, and then remove the repeat region, the table is now editable. Change few values if required. This saves too much of time and for sure u will escape from maddening data entry job

 

[Zaki]

for your first question Bart

1. making the part freeze in Assy
2. make the effected part features suppress
3. change the constraints or reposition the part in assy
4. edit the features one by one (some times it took more than a day or so)

This is my way to solve these kind of problems.
For PTC questions, I don't want to share my comments about those guys.

 

[pjw]

You would either have to freeze the component placement or redefine it as you would have problems redefining the features on either the component or assembly during fail mode. So design-engine - A,B & E are not valid options.


Iwouldnormally freezethe component placement if the constraints were to stay as they were but I was going to make a feature modification that would render the constraints valid once again.


Why did you ask the question though? I would have thought you were further on than this with your experience and the classes you teach?


Phil
Edited by: pjw

 

[dgs]

I see two ways of looking at the BOM question.

If evaluating the entire statement as a whole (this is the one and only way to create a BOM table), I'd say false. Yes, one can, and perhaps should, automatically create a BOM table via repeat regions, but you don't have to.

The second way to look at it is to treat the first sentence as a statement "A BOM Table is manually created" and then evaluate if that means that the user must then manually fill in the data. In that case the answer is true.

I guess there's a third way to interpret it which is to decide if creating a manual table is the right way to do it. Then the answer would be true, but perhaps open to a bit of interpretaion. There are circumstances where a manual table is the better way to do it.

Not well worded. What's the answer they are looking for?