What happened to constraints?

[B Castle]

Ok, since the move to 2018, I am having a miserable time with constraints. I included a straight forward drawing. There are 6 circles of fixed diameter and fixed centers. I am trying to take the smaller free circle and make it tangent to two of the larger fixed circles. I used to do this all the time with no problem, but all of a sudden in 2018 I repeatedly receive the "Constraint cannot be applied" error.

In the past I could constrain it to two circles, drag the center to influence the approximate size, and then fix it with a nominal radius measurement, but no more. Could someone please tell me what it is I am missing. This seems like pretty basic 2-D stuff...

 

[albie0803]

Seems like a bug as it works in sketches.

 

[Lew_Merrick]

In the past I could constrain it to two circles, drag the center to influence the approximate size, and then fix it with a nominal radius measurement, but no more. Could someone please tell me what it is I am missing. This seems like pretty basic 2-D stuff...

My thinking on the subject is that a Drawing is supposed to be :sourced" to a Model. ???

 

[HaroldL]

Remove the Fixed constraint from the two large circles you want the small circle to be tangent to and it works.

 

[B Castle]

I felt as though it was a bug, but I wanted to make sure that there wasn't some process hierarchy I was missing. Either way it is very inconvenient for me. I often spend a little time sketching out things like this before I begin to actually model as these wind up being important driving features.

I believe a drawing CAN be sourced to a model, but see no reason why it needs to be. Custom symbols would be a good example of a drawing that is not sourced to a specific model, as well as page layouts and such. Before 2018 upgrade all the constraints worked fine unless something was actually over constrained, I've used this method of creating features for years in Alibre 2012.

Removing the fixed constraint solves the initial problem of allowing the tangent to stick, but offers a new set of constraint glitches. After the tangent constraint is applied the system will not allow me to fix the diameter of the large circle in the 10 o clock location. As I mentioned, after the tangent restraint is applied, I want to drag the center of the small circle to a location that suits my needs, and then I choose a nominal radius size to finalize the geometry. Right now if I try to do that it drags the larger circle to accommodate the movement, which is not what is desired. Don't misunderstand, in this case I CAN dimension the diameter, X pos. , and Y pos. of the larger circle to "fix" it in place as a work around, but I see no reason why I should have to, nor do I see why constraining it with measurements works, but constraining it by fixing it does not.

Please note that this is only the most recent aggravation I've had with constraints, I often get documents in DXF formats with inconsistencies I need to remedy as well as PDFs that I transfer to vector drawings, then to DXF, and then have to doctor in such ways to get accurate geometries. I've been frustrated with the lack of any focus Alibre has had with the 2D side of their product (such as the lack of simple hole charts), but now that the constraints are non functional too after purchasing the upgrade, I'm wondering if I chose poorly. I've loved this program as a solid CAD system for years, but they need to realize the importance of being able to to function in 2D space as well...

Thank you for your responses in trying to help me with my conundrum, I hope everybody has a wonderful Independence Day!!

 

[DavidJ]

Remember that the 2D constraint manager has been replaced with an updated version, also that the entire software has been moved to a more modern development platform.

If a particular change of behaviour is problematic, please feed back to support with as much detail as possible about your workflow, what has changed, and ideally a simplified example with a repeatable set of steps to generate the problem.

Some regressions have been located in v2018, those verified by QA get passed to Development to correct.

 

[Lew_Merrick]

This is one of the "issues" I have with "modern CAD philosophy." What about (say) schematics (electrical, pneumatic, or hydraulic)? What about Logic Diagrams? Etc. They need a different 2D CAD approach than is common with the 4D Model -> 2D Drawing approach, yet they are [art of the (if you will) Documentation requirement set.

 

[HaroldL]

As good as Alibre is with 3D, I, too, think the 2D Drawing environment could use a bit of a "face lift" as well. From my experience with CAD, having only used AutoCAD v10, 12 and 2000; CADAM, I-DEAS and now SolidWorks, I think I-DEAS Master Drafting had the most user friendly interface and usability of the group. (Others may have a different experience and/or opinion.) I think it would be a nice enhancement if Alibre adopted the same 2D drawing capability as I-DEAS Master Drafting. Sadly, I-DEAS was bought by Siemens and incorporated into NX and bears no similarity to the original. Too bad that the drafting module could not be licensed and added to Alibre. (Just my opinion.)

I-DEAS Master Drafting allowed you to create empty views on the drawing to which you applied a view scale and then could sketch your design. Each view had a view border defining a window into the view which you could resize as needed. And you needed to select a view to draw in it. If you started with a Front view you could then project unlimited lines to the Top, Side or Bottom views which were then trimmed to create the developed Top, Side or Bottom projection of your design. Each drawing command and option was selectable from an Icon panel or with a 2-letter keyboard shortcut. I could in most cases, for example, complete a layout drawing using only the keyboard and very infrequently access the Icon panel except to access some custom macros that I created to create hole tables or print the drawing. The 2-letter keyboard shortcuts were especially helpful when dimensioning. Once learned I could access all the dimensioning options for each dimension applied, such as suppressing arrows and/or extension lines. You could also, as I recall, easily combine views from a 3D model and a 2D sketch on the same drawing sheet without any issues.

By chance, we had a visit to our company from a couple of the developers of Master Drafting and talked briefly about their philosophy in developing the software. Turns out they actually talked to drafters and designers to see how they worked and what they would like to see in the software. Seems like Alibre has adopted the same philosophy.

 

[Lew_Merrick]

Harold -- Having started out with Gerber IDS (in 1972), the 2D CAD package I preferred was Generic CADD followed by General CADD (the 2D packare I still use as a "general 2D layout tool"). I created (back in the 1980's) a pneumatic/hydraulic schematic set that would also perform a rough "simulation" of said circuit. It would be exceptionally slick could we make such a "tool" that would (A) work in the Drafting mode that could (B) generate the basis for a Model of said circuit in the Modeling mode. That is where I would like to see some of the "Drafting effort" be placed!