topic Re: Revolute joint with limits gets stuck on one side during rotation (Mac OS 10 in Fusion Support Forum

Revolute joint with limits gets stuck on one side during rotation (Mac OS 10.14)

Kawzon — Thu, 21 Feb 2019 21:18:40 GMT

Re: Revolute joint with limits gets stuck on one side during rotation (Mac OS 10

karina.harper — Fri, 22 Feb 2019 00:04:39 GMT

Can you please share the file? As I'm not able to recreate the behavior from scratch, I'd like to take a look at your file and see what there is to see.

Thanks!

Re: Revolute joint with limits gets stuck on one side during rotation (Mac OS 10

Kawzon — Mon, 25 Feb 2019 07:39:07 GMT

Sure, here is the file. I restarted F360, but experience the same behaviour. I'm sure I'm doing something wrong, but it just doesn't feel like an intentional interaction flow.

File on Dropbox

Re: Revolute joint with limits gets stuck on one side during rotation (Mac OS 10

TrippyLighting — Mon, 25 Feb 2019 14:10:50 GMT

I would suggest you go through the introductory tutorials in the Support & Learning sections.

Your small model already contains several incorrect techniques that will make things more difficult as you proceed in th design.

As as it pertains to assembly, one of the components needs to be grounded.

It's not a bad idea to familiarize yourself with Fusion 360 R.U.L.E #1

Re: Revolute joint with limits gets stuck on one side during rotation (Mac OS 10

Kawzon — Mon, 25 Feb 2019 14:15:01 GMT

Well, that's not quite the point here is it?

I don't care if the my "small model" contains several "incorrect techniques". It's an assembly of 3 parts where I believe the revolute joint doesn't maintain the expected interaction of the application developer. In short, it's a bug report.

The real question is, why are YOU responding with a "non-answer"? What does your reply contribute to this post?

Re: Revolute joint with limits gets stuck on one side during rotation (Mac OS 10

Kawzon — Mon, 25 Feb 2019 14:36:41 GMT

Hi again, I believe the joint interaction gets "stuck" when the current value equals on of the limits and therefore the rotation is disabled. Try the following: Rotate the joint until it gets stuck and without clicking anywhere, enter a value slight below the rotation limit and the rotation will once again be enabled. I think the bug got pretty obvious now.

Re: Revolute joint with limits gets stuck on one side during rotation (Mac OS 10

TrippyLighting — Mon, 25 Feb 2019 14:23:57 GMT

The answer is in my post. Please ground one part. Then the joint limits will be properly observed.

Re: Revolute joint with limits gets stuck on one side during rotation (Mac OS 10

Kawzon — Mon, 25 Feb 2019 14:26:24 GMT

No they won't. Try it out and then read my previous post.

Re: Revolute joint with limits gets stuck on one side during rotation (Mac OS 10

TrippyLighting — Mon, 25 Feb 2019 14:34:33 GMT

You are correct, that is unexpected behavior and looks like bug to me as well. Thanks for posting this!

I still would recommend for you to go through the tutorials, because if you did you would not have modeled this the way you did.

Re: Revolute joint with limits gets stuck on one side during rotation (Mac OS 10

karina.harper — Mon, 25 Feb 2019 17:22:00 GMT

Hi @Kawzon

This is an interesting one - I think his is happening because one component is a mirror of the other. When I removed the mirror and created a copy of the body using Copy -> Paste New in the browser tree, it seemed to work fine. Can you try that?

Re: Revolute joint with limits gets stuck on one side during rotation (Mac OS 10

Kawzon — Mon, 25 Feb 2019 19:07:26 GMT

Nope, it still gets stuck (like in the movie I posted above). I'm sure this has nothing to do with mirrors either. It's surely just a typo in the code for rotating a revolute joint. Anyway, deleting a mirrored component wouldn't be much of a "solution" either, the bug would be easier to find though.

Re: Revolute joint with limits gets stuck on one side during rotation (Mac OS 10

karina.harper — Mon, 25 Feb 2019 19:19:26 GMT

@Kawzon

I saw the behavior in the file you shared, but I was able to get it to work by re-building the joints and setting the limits. I'm not denying that this is an error but at this point I'm looking for what is causing it. It could have something to do with your hardware which is why I was asking you to try it for me. If you remove the mirror, create a new component and rebuild the joints from scratch does it give you the same behavior?

Thanks for your help

Re: Revolute joint with limits gets stuck on one side during rotation (Mac OS 10

Kawzon — Mon, 25 Feb 2019 19:26:34 GMT

Yes, I removed the mirrored component and remade all the joints and I'm experiencing the same behaviour. The rotation interaction "gets stuck" when the angle equals the maximum limit.

Re: Revolute joint with limits gets stuck on one side during rotation (Mac OS 10

karina.harper — Mon, 25 Feb 2019 19:43:29 GMT

Ok, that's good info. Thank you for your help and attention!

I've logged this with the team as FUS-47386 so they can start working on it.

Re: Revolute joint with limits gets stuck on one side during rotation (Mac OS 10

Kawzon — Tue, 26 Feb 2019 06:56:05 GMT

I didn't have any goal with this model, it's just some testing as I'm still learning F360. But since you mentioned it twice, what is it that you believe I should be doing different?

Re: Revolute joint with limits gets stuck on one side during rotation (Mac OS 10

TrippyLighting — Thu, 28 Feb 2019 16:28:08 GMT

Let me first say that I don't always do this for quick tests either, but in general it is a good practice fo fully constrain and dimension sketches. In Fusiosn 360 you can drag sketch elements in the viewport, even when you are not actively editing a sketch. While that can be very useful, it can also accidentally destroy your design.

In order to fully constrain and dimension a sketch some sketch element needs to reference the sketch origin, circled in red below. That can be with a constraint or dimension or both.

It can also be fully defined by referencing projected sketch geometry.

Once a sketch if fully dimensioned and constrained it all sketch elements will turn black (in the Infinity Pool environment). The sketch icon in the browser will get a pin aded to its icon.

However, the first thing to consider when starting a design if this is only for a single object or if this design is going to be made from several discrete objects. In that case you should not start with a sketch, but probably with making an empty component and activating it. I'l refer to Fusion 360's R.U.L.E #1 so I can save myself some typing here.

Then you use a cylinder primitive to create. whole. Noting "wrong" with that. But danger is lurking here. ON creation the primitives snap to geometry, but that snapping is not parametric, meaning that when you change the length of one of the arms the hole will not update accordingly and remain in the old position.

The next thing you'll notice is that all of your sketches are somewhat disassociated from the geometry that they were created with. Working with Fusion 360 R.U.L.E #1 will prevent thins IF you don't use the move body feature, which are the tow cross hair arrow icons in the timeline. This is a modeling tool and should not be used to move objects into location for assembly.

Re: Revolute joint with limits gets stuck on one side during rotation (Mac OS 10

rishabh.bisht — Sun, 29 Sep 2019 06:03:26 GMT

We squashed this bug with our recent September update. Please feel free to report back if you can still reproduce this issue.

Thanks!