Inventor 2019 Axis-to-Axis Mate Constraint Default To Forced "Opposed" Solution

[jletcher]

I understand you added it from someones idea, but why could you not have left the default selection the old way? This way it does not screw up other peoples workflows?

When on the fly this thing is now a nightmare. I don't understand why it was even needed but now more clicks more wasted time for me and others.

Make it so users can default to old style please, these are things you should be thinking when making changes. I understand you wanted to please someone but don't do it at the expense of others. You can leave it just change default default to old style, I will never have a need for this new way.

This is going to drive me nuts and many users have already called asking if there is a way to default to old.

This should be easy to fix.

kelly.young has edited your subject line for clarity: 2019 New mate constraint nightmare

[SBix26]

You would prefer that it default to Undirected?  Are you still unhappy about the Angle constraint adding the Explicit Reference Vector option and making that the default five years ago or so?

This is a more robust constraint than Undirected, saving you the trouble of users complaining about the constraint flipping directions on them.  Just inform users that Autodesk finally got it right and this is the way it should have been from the beginning.  They really can get used to new ways of doing things, especially when the new ways are better.

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Sam B
Inventor Pro 2019.1 | Windows 7 SP1
LinkedIn

[jletcher]

Explain why you think it is better.

I know for a fact you still have to put another constraint on it for it to be fully constrained so this is a nothing addition.

When putting on the other constraint you can control the direction.

And like I said I don't care you wasted time putting this in but default should have been kept the old way.

Please read my next post as well and find this is buggy as heck.

[jletcher]

After many complaints about this and complaints that a part with no constraints is showing conflicts when there is none I decided to play.

 I have found if I used the new style to control the part I have conflicts with parts with no constraints. After removing all the new constraints I have no issues.

This is not only a worthless addition but a buggy one as well.

Please look into this now that there are issues.

[jletcher]

Sorry I did not answer this.

Are you still unhappy about the Angle constraint adding the Explicit Reference Vector option and making that the default five years ago or so?

I still have not needed to use that option I still use the old style never had issues like everyone was saying they had.

[jletcher]

After playing some more I have found the issue only related to angle constraints.

Now if you accept the issue and just move the part it snaps into position and error goes away, but I am sure there would be all kinds of issues if not addressed further down the road like when you go to drive a constraint.

[Curtis_Waguespack]

Hi @jletcher,

Please try to take a moment and more clearly and concisely explain the issues you are seeing. I've read and re-read your previous posts on this topic and have not been able to follow what you attempting to report here, but I've attempted to take my best guess.

As far as I can tell the default is still the Opposed option, which is what it was in previous versions. The only change that was implemented as a far as I know is that when 2 axes are selected, the solutions buttons change icons, and a third un-directed solution become available.

In older version if you selected 2 axes the mate applied used the "closest solution" and if that was not what the intent was, we had to exit the constraint tool and rotate one of the parts to flip it, then use the constraint tool again. The improvements are intended to give us the option to flip the solution without exiting the constraint tool and rotating the part.

You seem to suggest that the un-directed solution is the default? I can not duplicate this. I do see that if I create one mate constraint between 2 axes using the aligned solution, then the constraint tool stays at that solution unless I change it. This is true of any of the solutions.

You mention "on the fly". I can't tell if this is the same issue, or a 2nd part to what you were attempting to report. Either way, for 'on the fly", are you suggesting that if I select 2 axes for a mate constraint, and choose the un-directed option, that you want the constraint tool to immediately default back to the opposed solution, so that if I choose 2 more axes I get that opposed solution every time, and not the last used solution?

That would be a departure from the behavior of what we see with other multi-solution constraints, such as the Insert constraint. When using the insert constraint, the default solution is Opposed, if I place one insert constraint and choose the Aligned solution, and continue on and place another constraint without exiting the constraint tool, the insert option remains at the last used solution, in this example it would remain on the Aligned solution.

So the new mate constraint options that help with axes mates, follow the same behavior as the insert constraint in this way.

But as mentioned earlier, I'm very much guessing about what you are attempting to discuss here, so if I've wasted time explaining these behaviors and they are not what you are questioning, please take the time to better explain the issue, and I'm certain someone will assist.

I hope this helps.
Best of luck to you in all of your Inventor pursuits,
Curtis
http://inventortrenches.blogspot.com

[jletcher]

At the start I did not have issues and just wished the default selection was undirected as before.

 The reason is simple, I found no issues with whatever the direction my part was because I have to put another constraint in to control the part 100%.

As we all know axis constraint does not fully constrain the part so a second constraint is needed and the direction of the part can be addressed at that time.

So to me it was a worthless improvement. I have no issues with it I just think the default should have stayed undirected so I don't have to change my workflow by selecting options I don't need.

I now have more clicks that was not needed I guess I am saying, and by defaulting to old I don't have that extra clicks or zoom in and out to find the arrows to pick the option I need to have the part flip in the right direction when I will use my 2nd constraint for that.

Does that clear it up any?

Improvements should not change workflows or add time unless it really has to. This could have been added and not change workflows or add more clicks if thought out.

 I did not address the conflict issues not to confuse you with why I started the post.

I should have started another for those issues, that was my bad.

[Curtis_Waguespack]

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@jletcher wrote:

Does that clear it up any? 

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Yep, I think I see it now.

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@jletcher wrote:

As we all know axis constraint does not fully constrain the part so a second constraint is needed and the direction of the part can be addressed at that time. 

So to me it was a worthless improvement.

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I think this is where the misunderstanding is coming from. With this new option, if you use the Opposed or Aligned solution for mating two axes, the 2nd constraint is no longer required, because it removes an extra degree of freedom. And in fact, as you've noticed, if you try to add it you are informed that attempting to do so will cause an over constrained scenario. 

So basically the un-directed solution is only there to support legacy file sets that have old un-directed axes mates. There really is no reason to use the un-directed solution  going forward.

Understanding that the Opposed and Aligned solutions are removing a degree of freedom that the un-directed solution is not is likely where the misunderstanding of this is coming from.  I believe that if you explain to the users that are complaining about this issue, that the Aligned and Opposed solutions make the need for the 2nd constraint obsolete, and that the un-directed solution remains simply to support constrained file that were created before this option was added, they will see that this improves the workflow rather than negatively impacting it.

I hope this helps.
Best of luck to you in all of your Inventor pursuits,
Curtis
http://inventortrenches.blogspot.com

[johnsonshiue]

Hi James,

I know you and I disagree with many things but we also agree with many things at the same time. I am not going to respond to any other comment not related to the title, because it will just add to confusion and make this thread longer than it is necessary.

To be exact, the Mate constraint you are talking about is the Axis-Axis Mate. In 2018 and earlier, this type of Mate constraint is non-directional. It means as long as two participating axes are kept at the user-assigned Mate distance, it is a valid solution. This can cause problems. The user intent is to keep the mate direction (either aligned or opposite) but internally the direction can be flipped. It can lead to unnecessary constraint failures and wacky solving behavior.

Starting from 2019, we encourage users to use the new type so we default to one of the two (Aligned or Opposed). Which one is a good choice? The truth is that it depends. It depends on the geometry and it depends on their relative orientation and position. In theory, there should be a way to "figure out" what is most likely user intended direction. But, it is not trivial and it is not reliable. In the end, we still need to default to something. "Opposed" was chosen.

It is true that in some cases it will add extra mouse click to get the desirable direction. But, the benefit is to ensure consistent solving.

Many thanks!

[jletcher]

I disagree a 2nd will always be needed. If I was at my machine I could prove this.

axis constraint does only that no matter what option you pick.

you still have to locate the part from off axis. Video would be nice to show but I hope you know this.

i will be able to move the part along the axis so I need 2nd constraint to stop that, at that time I can control the direction of the part.

[johnsonshiue]

Hi James,

It really depends on the direction of the selected axes and also their spatial relationship. In some cases, the "Aligned" would be the same as the old "Undirected" but in other cases "Opposed" would be the same as the old "Undirected." This is why a persistent default can be problematic unfortunately.

Many thanks!

[jletcher]

It cannot flip with 2nd constraint never. And the second constraint is still needed for these new options. The 2nd constrain would be a face to face constraint. 

In all the years I have never flipped a part and not one of my clients had this issue.

I do lots of animation and that is where you find constant issues.

I would like to see a failure and I will show you someone that did not constrain their part.

I would like you to prove me wrong here.

[Curtis_Waguespack]

@johnsonshiue

I think I see the issue

Earlier I said that the opposed and aligned solutions removed a degree of freedom that the un-directed solution did not, and that statement was not actually accurate.

Those solutions remove 1/2 a degree of freedom (if that's a thing) and then when applying a 2nd constraint to prevent a part from translating along the same axis that the first was mated to, if you use a mate instead of a flush you get a constraint error warning. I think this is the issue that jletcher is trying to communicate.

So create an assembly with two cylinder parts. Ground one of those, and then constrain the center axes of both of them and use the opposed solution. Then add another mate constraint to the flat circular faces of the 2 cylinders to prevent the ungrounded on from translating along the axis.

Depending on the faces selected you might get a constraint error warning with the mate solution and need to choose Edit in the warning dialog and choose the Flush solution.

To me the preview is enough to indicate which solutions to use on the 2nd constraint, but I can see where if the user is not watching the preview, or simply has it turned off they will not see it.

[jletcher]

 Almost, but I seem to be failing at explaining. I need to get a mic and make a video with voice. 

The only issue I have is I want axis to axis old style mate constraint my default so I don’t have to change my workflow or anyone’s workflow or make more clicks because of the added options I never wanted or needed.

 @johnsonshiue This was a request on idea not a issue. I would have voted no for it but idea section don’t have a no option. It really is a worthless option and now cost me and many users more clicks and time. 

 I understand it was a request but don’t change how it worked leave old style default and new options just that a new option. You gave those users what they wanted but changed nothing how I used it. Now I have to change everything for no benefit. 

[WHolzwarth]

I have to admit, that I didn't spend much time in 2019 Beta; I'm trying to learn more of 3ds Max. So I did only a short test right now.

What did I notice?

- Once a 2019 axis mate has been applied, changing directions by editing is not possible anymore

- 2019 axis mate only works well in my expectation, if a position change is applied to the top-most part in the browser. See sample video. A free rotated part not on top of the browser jumps back into the positon line, but I'd expect the line following the new position of the rotated part.

[Xun.Zhang]

Hello Walter,

Specific to the problem you've introduced in the video which is not Inventor 2019 unique case, you can easily reproduce it in any legacy build without axis direction. The root is, you have to make one of part zero-freedom. 

Hello James,

Thank you for the feedback and there are rooms to enhance for sure. 

The fact is -

Some of customers do need direction way but some are not, so it seems that default to any of option is not perfect to everyone. Thus, default to Undirected is not perfect either, do you agree?

My question is -

Try to think it over, what is the best approaching way rather than simply set the default to Undirected?

Looking forward to the feedback and welcome everyone's comments as well.

Thank you!

[jletcher]

"The fact is -

Some of customers do need direction way but some are not, so it seems that default to any of option is not perfect to everyone. Thus, default to Undirected is not perfect either, do you agree?"

Anyone that knows how to use Inventor would understand this was a worthless option, if it was not me calling it out.

 If @Curtis_Waguespack or @SBix26 was to say this was worthless no one would question it.

Reasons it is worthless.

1) When placing parts in assembly I have the option to rotate my part on insert so the direction of my part can be done at that time if I wanted to.

Undirected axis constraint will not flip the part when placed.

2) The new options does not control the motion along the axis.

  Thus making a 2nd constraint a must to control that motion, at that time the direction of the part can be placed

My question is -

Try to think it over, what is the best approaching way rather than simply set the default to Undirected?

  I did think it over and you added a option that is worthless and now cost more time to do something and changed thousands and thousands of users workflows for nothing. Even if you wanted to put this in you should never have changed the default being undirected.

Thus making all users happy, you gave users a worthless option and you did not change users workflows.

[andrewiv]

Maybe I'm stating the obvious here, but if Inventor just remembered the last option that was used wouldn't that solve the issue and make everyone happy?  There are a lot of commands that I wished Inventor would just remember the last selection that I used instead of reverting back to default.

[Xun.Zhang]

Hello James,

Appreciate for these valuable comments! 

No, we respect you indeed no matter who speak out opinion, please don't think in that way. We respect every opinion and everyone can share the opinion for sure.

OK, Let's talk one by one.

1) When placing parts in assembly I have the option to rotate my part on insert so the direction of my part can be done at that time if I wanted to. Undirected axis constraint will not flip the part when placed.

This is true, because Undirected just match the minimal rotation of position for both components. However, before that, you have to free rotate at least one of component to the right direction firstly. Am I right? If so, why not to leverage directional way instead of the pre-rotation of component?

2) The new options does not control the motion along the axis. Thus making a 2nd constraint a must to control that motion, at that time the direction of the part can be placed.

Sorry, it is not that clear for me. I suspect you are talking about the constraint preview. If you have one constraint between these two shafts such as a mate for face to face, then, at least one of the directional axis constraint (opposed/aligned) may detect the confliction. In Inventor, if a penitential confliction was defected, the preview is not working and it is the way to show the penitential confliction. In this case, if the preview is not working, please switch to another direction to avoid the upcoming penitential confliction. In fact, it is the general Inventor constraint behavior for all kind of constraint preview.

Ok, Let's start with some pros and cons for Undirected and directional.

Undirected - Minimal rotation when preview; the result can flip if the component free rotation angle > 90 degree; Additional face mate (direction protection) is required to persist the result. 

Directional - Not minimal rotation due to direction option when preview; the result is persist no matter how to rotate the component; additional face mate (direction protection) is not required to persist the result.

Do you agree above assessment? if so, how about -

Directional - Not minimal rotation when preview by pre-determine the direction (opposed or aligned); the result is persist no matter how to rotate the component; additional face mate (direction protection) is not required to persist the result.

Please do not hesitate to provide your comments and hope you like it.

Thank you so much!