9 answers · asked · Lesson: Animation Intro · Course: Short Film Character Production

Piero's wings Flip

I am trying to do an acting show with Piero and his feathers seem to flip a lot. I am having a little more success using Fk than IK. Is then any trick I can do so the feather don't flip. Thanks

  • crew

    Kudos for diving into this course! And getting as far as the rigging chapter. Nice job 👏

    If you post a download link to your .blend file I'll be happy to take a closer look. The best way to do this is by uploading your file to Dropbox, Google Drive, Mega, or equivalent file hosting service then copy + pasting the share link here.

  • So here is the file. I have the wings in FK. How do I get the feathers to keep from flipping. Blender doesn't have a very good Euler filter which would probably fix it.


    • crew

      Hey bbkohls ,

      I have looked at your file. It seems you have a bit of gimbal lock going on.

      Have a look at Animator's Guide to Rotations, in this lesson waylow explains gimbal lock and how to fix it. It's part of the Animation workflow in Blender and body mechanics course.

    • crew

      Hi Brit,

      I don't have time to fully investigate but It doesn't look like Gimbal Lock to me.  I think it has something to do with the way the constraints work on MCH_fthrFlight_INT.000.L

      That type of flipping usually occurs when something hits 90 or 180 degrees and the computer solves it by flipping it the other way.

      Sorry I can't be more specific about this actual issue but a way to investigate is to find the point where it flips - ie find what control and where it flips, and then look at the parenting and the constraints.

      There have been some changes to the way Copy Rotation constraints work in their default state since that course was recorded, so it might be a case of looking at the way it was set up in the original course and then choosing the equivalent setting in the latest version of Blender.  (for example - if Kent used the 'offset' setting, you can choose 'offset (Legacy)' to have the same affect)

      I hope this helps.

      On another note, I have 2 updated videos on handling Gimbal Lock in the production pipeline right now (probably a couple weeks away)

      But that's not the issue here.

    • waylow Could a "Limit Rotation" constraint maybe work? If I remember correctly I had this problem when allowing a maximum rotation of 180 degrees so that I set the maximum limit to something like 179 degrees which doesn't look different to 180 degrees if seen from the distance but avoids any flipping. 

      bbkohls Really impressive work 👍! When watching your Piero animation in the ".blend" file above or your frosty guitarist here, I feel like I could learn a lot  from you when it comes to rigging and animating.  Your work is really an inspiration and motivation for me 👍! I find already Piero's rig absolutely mindblowing with all its dependencies and I still have to create the facial poses and the animation  🤯🥴!

    • bbkohls Since Kent offered you to take a closer look at your Piero rig, you just need to tag him theluthier

    • crew

      Hi @druerer

      A limit rotation could work but there are already 3 copy rotation constraints on the bone in question - which I'm not even 100% sure is the culprit.

      I don't exactly know how Kent built the rig, so I would have to either watch all the videos or pull it apart myself. (Kent would probably need to do the same because who can remember what they did more than a week ago haha)

    • crew

      I don't exactly know how Kent built the rig 

      That makes two of us 😅

      bbkohls I'm looking at your file now and don't really see a lot of feather flipping. Is there a certain part of the animation where it's happening a lot?

    • theluthier 

      That makes two of us 😅

      May I join the club ?! Then we're already three 😉😁! Your Piero rig is still mindblowing to me! I think, I'll have to build some bird rigs from scratch and by myself just to see what I've learned and in order to get more familiar with it.