Mirror With Joints

[Anonymous]

I would like to create a right wing that is a mirror of the left wing shown below including all of the joints.

The left wing is able to fold up as well as flex at the wrist and It can do this in any combination. It works perfectly.

When I tried to mirror the left wing, however, I couldn't find a way to include the joints so I ended up rebuilding them all; or trying to. Unfortunately, the new right wing doesn't work correctly. It folds up fine as long as its wrist joint isn't bent but If the wrist is flexed any amount, the wing freezes up and doesn't fold at all.

I've spend a considerable amount of time over the last few days trying to fix it but failed. It's all so close to being finished. If I can just get the right wing to work I'll be really happy.

I would greatly appreciate any suggestions, especially if there is a way to include the joints in the mirroring process. 

Thanks.

I've included the f3d file of the two wings together.

[Anonymous]

I think it might be best to not mirror them at all, this will be a source of trouble. Best thing to do is right click on the component and do a (save copy as). After you do this then re-import that and mirror the component then delete the original. You might have to redo your joints but this will eliminate the problems that are counter intuitive to how the mirror command should work but somehow doesn't.  This will import in unblemished like a clean slate to start from. Hope this helps. 

[Anonymous]

innovatem,

Thanks for the suggestions but I'm not following you. After I right click on a component and do a (save copy as), I get a new file, ... fine. Then you say to "... re-import that..."

What, exactly, do you mean by "re-import"?

Do I insert it back into the original drawing using "insert into current design"?

If I insert it back into the drawing from which it was copied, I have two instances of the component. Then I mirror the "re-imported" component (yes?) and delete what, the original component that was copied or the new component that was "re-inserted" and mirrored or both? 

In either case it resulted in a long string of caution signs and a bunch of errors.

Sorry but I'm not understanding this.

[Anonymous]

Let me look at your files and try a few things. Mirroring doesn't always work because of the history associated to how the components were generated. Exporting them out as copies then re-inserting them does help a lot in clipping some of their history. Then reassigning the joints fresh. Let me make an attempt. Let you know. 

[Anonymous]

Okay so first thing I noticed was that the right wing joint is behaving oddly. See image after folding it 90. The Left joints do not come undone. Also I noticed an artifact in that socket that may or may not need to be there? There is either something added or missing in the joint symmetry between the two sides. I'll keep playing around.. 

[Anonymous]

innovatem,

OK. I'll attach the file containing both wings and you can play with it. The appropriate joints are available (and labeled) through the top level Selection Sets. I've suppressed the Right/Left Wrist Joints motion link so you can see that the left wing works (with wrist flexion). If you flex the right wrist, though, the right wing freezes.

I'll also attach the Falcon 12 Full Assembly Unlinked file so you or anyone out there can play with the whole machine if you want. It has a couple of interesting motion studies that work pretty well to show the entire flapping cycle with the Power Stroke, Wing Pitch rotation and Wing Folding (lacking only the Wrist Flexion). I'm still tinkering with them.

[Anonymous]

Okay after much assessment I know what it wrong but can't explain why fusion is allowing it. The mechanics are slightly off.  Their should be an allowable 4th joint in the image provided. Now it is possible that there was one some time ago but something changed maybe in a sketch or something where fusion still treats it like a 4th joint but shouldn't. Scissor linkage in such a design should have equal length on all apposing sides with respect to each other for a perfect collapse as needed. The lengths on not equal and I think that Fusion sees the problem after you mirror everything but does not before. Fix the right wing and add a 4th joint until you see 4 flags. Then mirror it and all should work fine.. This was a tough one and I'm sure you were extremely frustrated as I was but I'm sure a bit more. Gremlins to blame.. Beautiful work by the way!! Love what you are doing. I enjoyed learning from your work! 

[Anonymous]

innovatem,

I appreciate your efforts but I don't think it's the source of the problem. There never was a joint there and so there was never a functional parallelogram to go awry. It's just another instance of a practice I used throughout the drawing. I left out many similar joints because they are not needed to make the model functional and I was trying to keep things as simple as possible. In an actual aircraft, yes, they would be needed but in the model, no. Every single drag link in the drawing has an actual assembly joint at only one end.

Then, there is the fact that the left wing has the same exact design and it functions perfectly.

So, I think there is something else going on. I've started building a new right wing as a separate drawing using mirrored components from the left wing, converting each of them to direct modeling units to strip away the histories and then deleting the left hand versions. Then I'll assemble all the parts with new joints. I don't know if this will solve the problem or not but I'm keeping my fingers crossed.

[Anonymous]

I got it to work and tested this. So I'm telling you what the problem is.
Don't overthink it. You have a binding action going on. You can't have a
scissor collapse if the sides are not the same length. Checking the
distances from the center of those pivots proves this. Why Fusion is
allowing one side to do this I don't know but it shouldn't.. That is why
the left side is actually proper and the right is not.

[Anonymous]

So I found another issue. I can't explain it though. I redid the joints and found a bug. I've posted it now for the team to explain or fix. I put a link below to upload the fixed parts that still don't seem to want to mechanically work even though all measurements, sketches, and joints show validity.  You are right, something is wrong. Starting over with fresh sketches will probably work. But this is similar to what I did, not exact but I do have 4 flags on the joints and still no movement.... Hmmm

http://a360.co/2bAkNrt

[Anonymous]

innovatem,

You got it to work and tested it?

You got the right wing to fold up while the wrist was flexed? That's great. I would very much like to see this. Can you attach the file?

[Anonymous]

Sorry to be confusing. I tested the collapse of a corrected scissor design closely matching the original. There is something going on in your environment maybe the grid or something because it's behaving rather oddly, keeps switching by tiny amounts, this is causing some strange behaviors that are hard to explain.  The attached file shows how the mechanics should collapse but the parts will not. Not sure what is going on. The test mechanics below are aligned to the parts above. This is definitely a bug I believe. I tried my best to fix this. No luck.. 

[Anonymous]

The wing can go down now and can actually fold while down but it goes forward instead of tucking up backwards. I'm sure you can apply some new motion studies and joint ranges as needed. I remade a few of the parts but don't have any extra spare time to help. Did my best let me know if you get your motions back up and running. 

[Anonymous]

innovatem,

Well, thanks for trying. I do appreciate your efforts. Likewise, my own latest attempts have failed to resolve the problems as well. I think I need to know more about the whole mirroring procedure, how exactly a mirrored component remains related to the original and how one properly goes about cleanly stripping away those relationships.

[Anonymous]

I think the last file I sent you will work out by the way. You just need to redo the joints, maybe delete a few. You should be back in business fairly quickly. Let me know if I'm worth a Kudo for trying here. Good luck, nice project! 

[Anonymous · Accepted solution]

innovatem,

I got the model to work correctly by going back in the timeline of my original drawing to where the problems first appeared and rebuilding the wrist joint from scratch. I found a couple of seemingly minor things (motion links) I had left out the first time around. That made all the problems go away.

I do appreciate your efforts but, since your additions made the drawing more complex and didn't solve the problem, I couldn't figure what was going on and had to give up on it. None the less, I'm giving you a kudo for jumping in and trying. Thanks very much.

[Anonymous]

I'm glad you figured it out and it was something minor and it actually could be fixed. Very cool project. Take care..