topic Re: Drive constraints in Inventor Forum

Drive constraints

Anonymous — Mon, 25 Jan 2016 15:35:56 GMT

How can I edit a driven constraint? I made a part move back and forth multiple times, and I want to change the position to which it moves for one of the cycles. But the little window into which I put the position will not let me change anything.

Re: Drive constraints

Marco.Takx — Tue, 26 Jan 2016 08:14:08 GMT

Every constrain can be Drive.

In the drive dialog you can change the Start end End position.

Re: Drive constraints

Anonymous — Tue, 26 Jan 2016 16:12:58 GMT

Thanks for the reply. That works OK, but it's not my problem. In Inventor studio I drive a constraint in several stages, but once that is done the only way to change anything is delete the entire constraint and start over. The attached file is a simple example. The mate constraint is driven from 2 inches to 6 inches over a time of 2 seconds, then back to 2 inches over the next 2 seconds (4 seconds from start), then to 9 inches for the next 2 seconds (6 seconds from start), and back to 2 inches (8 seconds from start). Suppose I want to change that 9 inches to 7 inches at time 6 seconds from start, or perhaps change one of the 2-second time intervals to 1.5 seconds. The dialog box will not let me type in any changes, or if it does I will get a message that says there is a time overlap.

Re: Drive constraints

JDMather — Tue, 26 Jan 2016 17:26:21 GMT

@Anonymous wrote:
... In Inventor studio I ~~drive~~ a constraint in several stages, but once that is done the only way to change anything is delete the entire constraint and start over. ....

First thing, have you installed all Service Packs and Updates for 2012?
I think you mean Animate Constraint rather than drive constraint.

I like to create a home position constraint (and perhaps Position Rep) and suppress that so that any time I need to get back to a starting position I can simply un-suppress and re-suppress.

I think you might be better off creating a named Parameter and Animate Parameter. Changing the parameter changes it everywhere at once.

But I think it all comes down to parent/child dependencies - just like everything else in a parametric software.

Re: Drive constraints

Anonymous — Tue, 26 Jan 2016 19:34:41 GMT

Thanks for the guidance. You are right - I should say animate constraint, not drive constraint. As you can see, I'm new at this. I downloaded all the service packs as you suggested, but that in itself doesn't solve the problem, of course.

I created a positional representation as the home position. And I created a named parameter for the mate spacing constraint, but Inventor Studio won't let me animate that. If I select parameter, it just says there are no favorite parameters defined. So I still have no way to make any changes in the constraint animation.

Re: Drive constraints

JDMather — Tue, 26 Jan 2016 21:16:11 GMT

There are a couple of tricks that I left out in getting Parameter Favorites.

Attach your new assembly here.

The method you were using would work - as long as you follow logic.

You cannot have an event exist in two different positions simultaneously (with later event before earlier event), so you must change the earlier event and then the later event.

Re: Drive constraints

Anonymous — Thu, 28 Jan 2016 17:20:07 GMT

Aha! That does it. Thanks very much. It looks like for the operation I want to change I have to select it on the time line, and the only thing I can change is the ending position. It also looks like the only way to change start and end times is to drag the time line. Now that you have educated me, I'm ready to forge ahead!

Re: Drive constraints

Anonymous — Tue, 04 Dec 2018 13:42:10 GMT

Hello,

I can not get the drive dialog box to appear after adding constraint and clicking drive?

in 2019 inventor

Re: Drive constraints

JDMather — Tue, 04 Dec 2018 13:46:05 GMT

@Anonymous wrote:

I can not get the drive dialog box to appear after adding constraint and clicking drive?

in 2019 inventor

Can you Attach your assembly here?

Re: Drive constraints

Anonymous — Tue, 04 Dec 2018 13:49:12 GMT

[cid:2b9dcd1d-a895-4434-b544-b804e5ca976f]

Re: Drive constraints

Anonymous — Tue, 04 Dec 2018 13:59:15 GMT

screen shot attached

Re: Drive constraints

JDMather — Tue, 04 Dec 2018 17:17:32 GMT

Can you use Assembly Constraints rather than Joints?

Can you Attach your assembly here?

Re: Drive constraints

Anonymous — Tue, 04 Dec 2018 17:30:31 GMT

same result, no drive dialogue box, in this simple example

Re: Drive constraints

Anonymous — Tue, 04 Dec 2018 19:56:20 GMT

I found the dialogue box hidden in other screen, Thank you anyway