topic Re: Caution with driving constraints in big assemblies in Inventor Forum

Caution with driving constraints in big assemblies

WHolzwarth — Mon, 01 Aug 2016 19:40:06 GMT

I just stumbled about this, and it took me some time to realize. But it is, as it is ..

D. Kohfeld put another amazing model into GrabCAD:

https://grabcad.com/library/lego-technic-helicopter-9396-1

But most of his models could be structured better in sub-assemblies. Otherwise animating them is a problem, IMO.

So I spent some time with re-structuring. I've added some decals, too. After that, in Modeling environment, I could do:

- Rotation of main rotor and back rotor

- Up-down movement of the crane hook and the winding drum

- Movement of the back door

- Movement of the retract gear

I could switch gearing couplings by posreps, and all was looking good. The main frame (Rumpf.ipt) was grounded.

In a next step, I tried a Studio animation. Tasks:

1. Start Rotor movement

2. Roll-up of crane hook

3. Closing of back door

4. Helicopter moves up against groundplane

5. Landing gear is retracted

6. Helicopter turns 180° around it's vertical axis

7. Helicopter flys away on a horizontal path

Well, I could do the first three steps. The next one needed un-grounding of Rumpf.ipt and adding constraints instead. But after that all my rotational constraints were inactive. Input shaft was turning, but no outputs at all. Similar problems were in Studio environment, and gearing movement was no more.

Conclusion for me: It's not possible, doing these 7 steps in Studio.

If any forum members, and especially Autodesk employees, would try it, I can place a download link (2016 files).

Walter

Betreff: Caution with driving constraints in big assemblies

WHolzwarth — Tue, 02 Aug 2016 20:28:01 GMT

I came so far, with several crashes. (mp4 in Zip attached)

I didn't find an easy way for eliminating the blue spots at the bottom of the screen at about 11 s

Download link to DropBox (about 150 MB):

https://www.dropbox.com/sh/6e92lgh0kaq0aze/AAAQID06Yjib0bQEzj5iVtzGa?dl=0

Comments are welcome

Walter

Betreff: Caution with driving constraints in big assemblies

WHolzwarth — Thu, 04 Aug 2016 20:40:47 GMT

Ok. Blue spots at the bottom could be eliminated by setting keyframes in Camtasia Studio (New mp4 in zip).

Good enough for old donkeys like me ..

Betreff: Caution with driving constraints in big assemblies

Henry.Huang — Mon, 08 Aug 2016 10:55:23 GMT

@WHolzwarth

I am try with your data and try create a simple assembly to reproduce the issue, have to say this assembly is too big for me.

Please correct me if I understood your question in wrong way.

1, Create a simple assembly.

2, in Studio, make some rotational constraints, and make a Constraint Animate with them.

3, Find the ground part, and un-ground it. Create some constraints with this part and make a Constraint Animate with it.

Now check if the Constraint Animate which created in step 2 working or not.

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Betreff: Caution with driving constraints in big assemblies

WHolzwarth — Mon, 08 Aug 2016 11:57:19 GMT

Hi Henry,

I was trying to reproduce it with a simple assembly, too, but there I couldn't see that behavior. A simple sample worked as expected.

I'll make another test later in the evening.

Walter

Betreff: Caution with driving constraints in big assemblies

WHolzwarth — Mon, 08 Aug 2016 21:40:41 GMT

I've tried it once more with the Helicopter sample, but no luck. I could get no movement up of Rumpf.ipt.

Who can do better?

Re: Caution with driving constraints in big assemblies

Henry.Huang — Fri, 19 Aug 2016 10:18:21 GMT

@WHolzwarth

I checked with our developer with your data, we noticed here has a lot of rotation in this assembly, right now, inventor may has some issue with rotation in studio. If your rotation parts are related with ground part, and then you un-ground it, in studio environment, rotation will not work.

For you movie, please correct me if i understand your need in wrong way.

you need propeller rotate, and then helicopter move up.

I think you could create a part and ground it, and set all rotation parts constraint with it. Then go to studio, create animation timeline.

I attached a sample for you test and an video for your reference.

http://autode.sk/2b5I7MQ

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