Inventor doesn't warn when some refs get broken. Do you think this is a problem?

[DRoam]

Inventor usually does a really good job of  warning us when references to upstream geometry get broken. Sometimes it even goes a step further, and prevents us from doing things that would break references in the first place (like preventing us from deleting a User Parameter that's referenced by other parameters in the same file).

However, there are a few parameter-related situations where Inventor not only doesn't warn of broken references, it goes out of its way to create new "dud" parameters so that even though the original relationship is broken, no warnings are thrown.

While I can see some advantage to this (reduced warnings), in my opinion it subverts something much more important: Our dependence on Inventor to either maintain the relationships we set up, or let us know when it can't.

In my opinion, this is a big issue and needs to be corrected. I'm writing this post to see if other users of Inventor agree.

To provide some background, there are basically two situations that lead to silently-broken parameter references:

1. A Driven Dimension is created in a sketch. Its associated Reference Parameter is "ParamX". A few other sketch dimensions reference ParamX. But then the Driven Dimension gets deleted. Rather than remove ParamX and warn of the broken references by the other dimensions, Inventor silently keeps ParamX sticks it under the Model Parameters. But this parameter is not actually a Model Parameter -- it's not associated with anything in the model anymore. So all references to it are referencing a dud.
2. A part called "SourcePart" contains a parameter called "ParamY". A part called "RecipientPart" derives in "ParamY" from SourcePart, and has some parameters that reference ParamY. But then ParamY gets deleted from SourcePart. When RecipientPart is updated, rather than remove ParamY and warn of the broken references by other parameters, Inventor silently keeps ParamY and sticks it under the User Parameters. But now all references to ParamY are referencing a dud.

If these situations sound like an issue to you, please let the Inventor team know by voting on this idea, or by commenting here (or both).

Or if you disagree that this is an issue, please comment and explain why as well.

Thanks for your feedback.

[DRoam]

As an analogy, imagine this situation: A part contains a face that's used for a downstream extrusion and some assembly constraints. At some point, the feature that created the face gets deleted. But rather than warn of the broken downstream references, Inventor silently creates a static Work Plane where the face used to be and uses that to keep the downstream features and constraints in tact. This prevents any warnings or broken constraints, but at what cost? Inventor has completely undermined the relationships the designer set up to the face. Now rather than warning him so he can fix it, Inventor has covered it up. So the designer may never notice the broken relationship and correctly repair it.

This exactly what's happening in the two situations above, almost word for word, but with parameters instead of geometry.

[cadman777]

Gentlemen,

I still run IV2010, and the DEFECT expressed in this thread exists in my version. That's a whopping ONE DECADE LATER with no fix in sight for this DEFECT. I'd complained about this to tech way back in the day, but my complaints fell on deaf ears. My guess is, Autodesk wants YOU to remedy this defect by writing an iLogic or VBA script to warn YOURSELF when these things happen. After all, THAT is why Autodesk gave us the API!

Anyways, this DEFECT in the software has come back to bit me in the arse many times over the years on large project. That's why I do my level best to operate on the KISS principle, meaning I've use only about 25% of the software for most of my projects, regardless of how 'nice' it would have been to use other functions of the software. But with DOWN-STREAM CONCERNS in mind, Autodesk/Inventor has forced me into this posture.

However, when customers want a rush-rush project done, I've been forced to use all available tools in Inventor, which results in a MEGA ARSE WHIPPING down-stream. One such DEFECT is the C/C editor which won't allow the use of Parameters in Trim or Shorten/Lengthen scenarios. There are many other DEFECTS like this in Inventor as well. No point in beating a dead horse!

Good luck getting this DEFECT fixed, since it's found throughout the program.

Cheers ... Chris

[johnsonshiue]

Hi Derek,

The behavior does not sound right to me. I tried a very simple example and I am not getting the grounded workplane. Could you send me the example (johnson.shiue@autodesk.com)?

Many thanks!

[DRoam]

Hi Johnson, the workplane anecdote was a close analogy to what Inventor does with parameters. Haha and I agree, it does not sound right. If Inventor did this with geometry it would be very bad. But this is exactly what it does with parameters in the situations I described.

[johnsonshiue]

Hi Derek,

Please feel free to send me an example directly (johnson.shiue@autodesk.com). I would like to understand the behavior better. If you have reported a problem report about this on Inventor Beta, please let me know too.

Many thanks!

[DRoam]

Hi Johnson, I provided example workflows that demonstrate the issue in the original post of this thread, as well as on the idea and my comments on it (see Scenarios 1-3). You should be able to recreate the issue using those. If you need more details let me know.

Whatever the case, it appears not many other users consider this as serious an issue as I do. I'm surprised by this -- surely many Inventor users use parametric relationships and want them to be dependable. But this hasn't gotten the response I expected. Although, it wouldn't surprise me if most users aren't even aware it happens to them, precisely because Inventor covers it up completely silently. But I have no way of knowing if that's true. Perhaps the Inventor team could find out with some analytics.

If analytics or other investigations show this happens a lot, I think it's worth at least adding an option like:

When the source of a parameter (e.g. Driven Dimension, Part Feature, Derived Parameter) is deleted, but the parameter is used in other formulas:

   [  ] Legacy: Keep the parameter as a static, "orphaned" parameter to prevent warnings (parametric design relationships will be broken).

   [  ] Delete the parameter and cause all dependent parameters to become sick and appear in the Design Doctor so they can be repaired.

That way companies at least have the option to set up their machines such that their designers' Inventor models aren't filled orphaned, dud parametric relationships.

[cadman777]

Since this DEFECT in the software was of such magnitude to me in the past, way back in the day when I tried getting a solution to it from Autodesk tech (and failed), I set out on my own to find a remedy. It seemed reasonable to me that 'someone' created an add-in that would show me all the Parameter INTER-RELATIONSHIPS in all the files in a project, so I could MANUALLY trace ANY Parameter to all of its children. I wanted that MAP so when a parameter got lost or deleted I could FIX the CHILDREN that possessed that Parameter. Sadly, that quest proved unfruitful.

I consider this a MEGA DEFECT in the software. The FACT is, the key to PARAMETRICS is having software that DOES ALL THE DATA MANAGEMENT WORK FOR YOU WITHOUT WORRIES, b/c the bigger the project, the exponentially bigger the DATA MANAGEMENT WORK. Nobody seems to get this at Autodesk.

I recently discovered (from someone on the inside) that the ONLY software that Autodesk actually developed in-house was INVENTOR (and even that is questionable). ALL the other programs they 'own' (including AutoCAD!) have been 'acquired' from 'others'. IOW, Autodesk is NOT in the business of SOFTWARE DEVELOPMENT. Instead, they are in the business of CAD MARKETING and CAD MARKET CONQUEST. In the final analysis, it's all about the MAMMON.

Cheers ...

[johnsonshiue]

Hi Derek,

I am sorry I missed your tagged thread. I rarely go to Ideas forum, since there are tons of threads on the General forum already. I will take a look at the idea and understand it better. But, I think we might have discussed this on the Beta forum before.

https://forums.autodesk.com/t5/inventor-ideas/references-to-deleted-sketch-dims-amp-feature-paramete...

Regardless, there is always room for improvement. How to or when to address the issues is a separate discussion. I need to understand the issues better.

Many thanks!