Rig: Mecha Cat

Nico Strobbe posted a rigging-challenge over at CGCociety in 2010, he has provided a stunning model of a mechanical cat consisting of 437 different parts which can be downloaded here:
http://forums.cgsociety.org/showthread.php?f=216&t=907295 

I started to rig this creature about a year ago, being my first attempt at mechanical rigging I quickly ran out of ideas on how to rig the legs properly, so I gave it up.

However I picked up the rig again about two months ago, starting from scratch on the entire thing, after a hard struggle I finally managed to figure out how to solve the legs (which is the key to the entire rig) and complete the rest of the rig.

Here’s the rig-presentation:

 

I intend to make a breakdown-video eventually, just gotta find some time for it :)

12 comments

  1. Rahul Mishra says:

    Hello,
    i just saw your mechanical rigging reel “Mechcat”. I really inspired by you by this reel.

    Can you please just tell me about good tutorials on Mechanical rig and dynamics reel ?

    Sorry for bad English.

    • Jorn says:

      Thanks Rahul, it’s cool to hear that it inspired you :)

      I’m sorry to say that I don’t have any tutorials to recommend, I searched around for mechanical tutorials myself when I was working with this one, without any luck :( There might be some good mech tutorials out there, but I couldn’t find anything, other than tutorials covering basic stuff.

      I’m going to create a breakdown for this rig though, where I’ll talk a bit about my approaches.

    • Greg Hendrix says:

      The Art of Rigging books from CG Toolkit are a really good resource for mechanical rigging. The URL is http://www.cgtoolkit.com/ but their website seems messed up right now, but maybe you can find where to buy them somewhere else.

  2. Jonathan Strong says:

    I must say, this is the most beautiful presentation of a rig I’ve ever seen. The transitions, animation, effects, everything about it is elegantly presented and extremely polished. Also, I love the choice of music ;)

    I’m very interested in what you’ve done with the tail. It looks sort of like an interactive simulation. I’d love to hear about how you set that up. Also, I’m curious, did you do anything to automate the metal plates on the tail and spine?

    Congratulations on the great work!

    • Jorn says:

      Wow, thanks for the nice words Jonathan! :D

      The tail has a hair-curve which is driving a joint-chain through the ikSplineHandle, the input curve is skinned to the rig-joints so that you can adjust the dynamics relative to the original animation.
      I believe Zeth Willie have a tutorial for that kind of setup on his vimeo-account: https://vimeo.com/zethwillie :)

      The metal plates on the tail and the spine have automatic animation through SDKs, they’re getting driven by the rotation of the different parts along the tail and the spine. Nothing fancy ;)

      • Jonathan Strong says:

        Very cool. Thanks for the tut. Seeing your rig move so beautifully makes me want to go back and redo mine! Also, I just noticed. You removed the wheels that were originally attached to the cat’s feet. What prompted you to do that? Just curious.

        • Jorn says:

          No problem :) Yeah you almost got it finished, but you had that offset on the foot, right? The reason why I removed the wheels was that I couldn’t see them having any purpose for the character, and I thought the cat looked better without them :)

          • Jonathan Strong says:

            Yeah, I had a usable full-body rig, but the feet were pretty buggy. I’m going back now and reworking it. The wheels always did seem a little wonky, but I thought it was hilarious when I imagined the cat rolling around on them. :)

            • Jorn says:

              Hahah, now when you say it, that would indeed be hilarious :D Give me a peep when you get it finished, it would be interesting to see some different approaches on the legs.

  3. Tang Tao says:

    Hi, this rig looks really awesome.
    I am stuck to rig the leg because I set up three joints to control each axis of the thigh joint and lock their unused rotation. But it doesn’t work when I set IK. What exactly you did for this part? Thank you so much

    • Jorn says:

      Thanks :) I’ve been planning to create a rig breakdown for this for quite some time now, I’ll try to make some time for this soon. But yeah, the legs are tricky, the way I did it (if I remember correctly) was to create a duplicate leg-joint, and then drive the out-rotation of the upper leg with that, then I used an ikHandle for the parts that was offset as you can’t drive them by just connecting the rotations to the different parts because of the offset. I’m sorry for the brief explanation, I think I’ll have to dig up the rig again to go more in detail :)

  4. pavith says:

    wow… awesome stuff man… hope u do the breakdown soon …

Leave a Reply

Your email address will not be published. Required fields are marked *

* Copy This Password *

* Type Or Paste Password Here *