Part won't move with one constraint

[BCrosby]

I am placing components in an assembly model and constraining them. After placing one constraint on a part, it is locked down and will not drag. Any thoughts?

• The red cross is not on
• No grounded parts
• No sick contraints

[Cadmanto]

My thoughts are I have experience this.  Usually if I shut down Inventor and come back in it fixes it.  Otherwise there is still this command if you need it.

Windows 10 x64 -16GB Ram
Intel i7-6700 @ 3.41ghz
nVidia GTS 250 - 1 GB
Inventor Pro 2018

[johnsonshiue]

Hi! This usually means there are pre-existing failed constraints. Inventor fails to find a good solution in such state. Could you fix up the pre-existing failures or simply delete the failed constraints? After that, does it work now?

Many thanks!

[BCrosby]

Inventor doesn't give me any indication that there is a problem. I only know that when I place a component and one constraint, I can no longer move it. My experience tells me there has to be another issue somewhere but I can't find it. The red cross is not on indicating an issue.

[johnsonshiue]

Hi Bruce,

If possible, please share an example here or send it to me directly ([email protected]). I would like to understand the behavior better.

Many thanks!

[3D4Play]

I have exactly this same issue. Applying a single constraint for one DOF to a component causes behavior as though the component has been grounded, complete with the "no dragging allowed" icon when I try to drag it after placing the constraint. I just submitted a support case for it, along with a dataset -->CaseNo:14239457. I've marked it critical because it is negatively impacting productivity. I will also email it directly to you Johnson, as it is only about 12 Mb

[johnsonshiue]

Hi! I will take a look and understand the behavior better and get back to you.

Many thanks!

[johnsonshiue]

Hi! I took a look at files you shared with me. This is a case of lacking grounded component. All of the first-level components are free to moved (some are constrained). But, none of them is grounded. I would ground at least one of the components to reduce degrees of freedom. You will find after doing so, the constraint will work.

Many thanks!

[3D4Play]

I did ground a component that was already fully constrained. It had not effect on this issue. I've followed up with you via email with screenshots.

[Anonymous]

I've got the same problem. after one contraint the component will not move anymore. I also have at least one component grounded how did you solve this?

[MoshiurRashid]

Constrains and joints are nothing but making the Degree of Freedom of a part more controlled. You might have constrained your part as there is no degree of freedom left.

[JDMather]

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@Anonymous wrote:

I've got the same problem. after one contraint the component will not move anymore. .

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Does Manage>Rebuild All return any errors?

Are there any issues indicated in your Relationships folder?

Attach your assembly here and end all doubt.

[johnsonshiue]

Hi! Please share an example exhibiting the behavior. Without the files, there is not much I can do.

Many thanks!

[Anonymous]

I'm having the same difficulty. I know it's almost always something simple but i'm blank. I've looked at everything I know. Has there been any resolution to this issue?

[johnsonshiue]

Hi Phillip,

The behavior is certainly wrong. But, without seeing the files, I can only guess. Try the followings and see if they help.

1) Ground a major component.

2) Activate LOD:Master and go to Manage -> Rebuild All.

3) Delete or suppress or fix up all the sick constraints.

Does it work better now?

Many thanks!

[mp]

Hello. I had the exact same problem and the solution was to delete a component pattern from the assembly, apparently, there was something wrong with it, but I had no errors 🤔

[3D4Play]

I have same and similar complaints going back to 2018. Fully constrained components should be in effect the same as a grounded component. Patterned components built from either a grounded, or a fully constrained, base component should cause no issue when constrained to. Etc, etc.

That said, I've learned to double- and triple-check the source of constraints to make sure you are constraining to a(nother) fully constrained element. Another way to think about it is to consider the contraint chain - what is being constrained to what, and how far backwards do you have to go in the constraint chain to get to something else fully constrained.

I work in patterned assemblies all of the time. I try to only constrain to fully constrained elements, so the constraint chain is strong. A patterned component is not really fully constrained - though it seems like it should be. 

If the constraint is intended to be "driven" by a patterned component, then make sure the patterned component is driving the pattern, not part of the patterned components - otherwise that patterned component will need to be individually "overconstrained", or grounded.

I have also had to delete patterns, in the pathway to "redo".

I don't know if it will help you here, but it has certainly been a long and painful lesson I've learned over the years.  

Just my .02 

[johnsonshiue]

Hi! There are several reasons a component may appear locked up. If possible, please share the files here. Forum experts and I can take a look to understand it better. Did you try Manage -> Rebuild All?

Many thanks!

[3D4Play]

Shazam! This exact thing just happened to me. I closed then reopened Inventor, nope. I rebuilt all. Nope. I deleted constraints. Nope. I added a constraint and the component went right where I wanted it....but it would NOT drag there. I did a free move, dragged the component off-position, exited the move command, then flexed the component to watch it pop back into its "locked" position. After playing with it for a few minutes, I discovered that the component would let me drag it once, after it popped back into position, as long as I kept the mouse button depressed. It is replicatible, and I do have a video. Johnson....your turn! Send me an upload link and I'll let you work your magic.

[3D4Play]

@johnsonshiue The PNG dataset ended up being smaller than anticipated, so I emailed it to you.