Jump to content

Sign in to follow this  
bnine

Rigging a strap / chain

Recommended Posts

  • Topic Author
  • I've tried to duplicated the result in one of the project files sent over in previous posts but my cage gets all whacky and I dont know how to connect the cage to the mesh. Not sure what I am doing wrong or not doing at all. Do you have any spare time, @Cerbera?

    Dont stress it if you don't :)

    Ben

    Share this post


    Link to post
    Share on other sites

    Oh man - I started writing you a reply when you posted this, but then got buried under a hurricane of work - sorry about that.

     

    We need to test that cage mesh you have built with the spline dynamics of earlier. If you are saying that goes mental, we need to solve that first before we do anything else.

     

    Let's copy that low poly cage to a new scene, then bake it down to a single mesh with COaD, and attempt to make that work with the dynamics. Do that for me, and if no joy, pls upload that version of the file and I'll take a look this evening.

     

    CBR

     

     

     

     

     

     

    Share this post


    Link to post
    Share on other sites
  • Topic Author
  • No worries, @Cerbera. I will try that as soon as I can, hopefully later today if I have the time. Just wondering because I couldn't find the answer from google, what is COaD? 

    The cage actually is just whacky in the beginning, but after playing it through it falls nicely like a strap would. But from frame 1 - 30 (roughly) it is for some reason rotated the wrong way and "whacks" in to position (if you get my point :) ). 

    I know all of this stuff is probably a bit above my skill-level, but this is for a personal project / self-development project and I truly appreciate the help, @Cerbera

    Thanks, man! 

    Share this post


    Link to post
    Share on other sites

    COaD = Connect Objects and Delete (from right click menu in Object Manager). You might have to make the cloners editable objects before you do this, by selecting them and hitting C (make editable).

     

    We can probably fix the other issue by playing through until the first point it seems stable, then stopping it there and hitting Set Initial State in the Spline Dynamics properties...

     

    CBR

    Share this post


    Link to post
    Share on other sites
  • Topic Author
  • Thanks for the reply! I tried COaD'ing my cage but it's still the same. I got a feeling that it is my spline that's doing it. I'm not sure how I would set it up since there should be two splines technically. One on each side to get a realistic bend and slight twist. Im not quite sure where the spline should go (in the middle of each link or between. And what is a rail and why do I need that?). 

    I've uploaded my file below for you to view. 
    Casio_0039_c4dCafe.c4d

     

    Thank you. Again. 

    Ben

    Share this post


    Link to post
    Share on other sites

    Yes - Connects are no substitute for a single editable mesh here, so I did that to (copies of) both your cage and the final mesh.

    Then we needed the rail which is what is responsible for stopping that rotation thing at the beginning you were getting...

    Then I had to re-align some stuff and make some subtle changes to the Splinewrap, and then things started doing what they should be doing...

     

    OK, so here's the base of that setup working with spline dynamics, rail, object collisions and the mesh deformer, so we have reached Level 1 - we've established that the plan might work ! :)
     

    Casio_0039_cbr.rar

     

    Next step is to work out how we will manipulate the rail to facilitate any twisting you need going on, and I'll have to have a think about that, because really we need it following the dynamics of the first spline whilst also doing its own independent thing down the length of it...

     

    I think I need to know in quite some detail what animation you are planning now, so I can find us the most suitable way forward...

    Depending on what sort of twisting you want we might be best doing that with otherwise animated, non-dynamic splines, or via invisible colliders if we find the rail too difficult to manage whilst also keeping it proportionally relational to its source spline.

     

    CBR

     

     

     

    Share this post


    Link to post
    Share on other sites
  • Topic Author
  • That's so cool! Thanks for the help so far!

    So I know what kind of shot I want. Basically I want to position and rotate my watch when revealing it. I've made a quick mockup (white part is the watch body and the blue parts are the straps). I really want to get some dynamic in there to get a realistic feel to it.  Not sure if I get the point across with the video, but the summary is that I want the straps to sort overshoot either behind or in front of the watch (with some stiffness paramters so it doesnt act like a chain). 

    Her is a mockup:
     




    Thanks again, @Cerbera!

    Share this post


    Link to post
    Share on other sites
  • Topic Author
  • What do you reckon, @Cerbera? This is also an animation I want to do. Have the watch fly towards the camera with dynamics on the links (so that the strap keeps going when the watches stops - they sort of fly towards the camera). I've added a preview below (this is with pure keyframes. It's going to be too hard to keyframe realistic dynamics to those straps with a bend / twist deformer). 

     

    Share this post


    Link to post
    Share on other sites

    Ok I have briefly tested that rig with both the twist and the movement, and both seem pretty much fine once you've made a few adjustments to the spline dynamics (rubber >100% being the most important setting, although turning on Rigid may also help stiffen things). You can check this by giving yourself a massively long timeline (turn the collider cylinder off for now), then press play, wait for gravity to drop it to vertical, then move / rotate the target null while playback is happening, and you should see that things move and twist quite nicely. Tweak the spline dynamics tags of the main spline and the rail concurrently, the repeat the movement / rotation tests until it is mostly doing what you want. 

     

    The next stage of that plan would be to expand the rig to include the end clasp bits (so single segment box around it for the cage), and then to duplicate that whole setup for the other side of the strap. Then we should make a group null into which would place the watch face and all the rigid parts, the 2 target nulls and the cage geo. Now you can animate that null, and everything should go with it, and both your straps should do their dynamic things automatically. You may have to disable gravity, or alter the orientation of the model so that gravity is working for you rather than against you as it is at the moment starting out flat down Z , whereas your animation previews seem to want it hanging vertically, so your initial position should ideally be that.

     

    I wish I had time to do all these tests myself, but I just don't at the moment - too much client work on, so I'll have to leave that with you to experiment with until it all calms down a bit...

     

    Hope that helps a little...

     

    CBR

     

     

     

    Share this post


    Link to post
    Share on other sites

    Join the conversation

    You can post now and register later. If you have an account, sign in now to post with your account.

    Guest
    Reply to this topic...

    ×   Pasted as rich text.   Paste as plain text instead

      Only 75 emoji are allowed.

    ×   Your link has been automatically embedded.   Display as a link instead

    ×   Your previous content has been restored.   Clear editor

    ×   You cannot paste images directly. Upload or insert images from URL.

    Sign in to follow this  

    • Recently Browsing   0 members

      No registered users viewing this page.

    ×
    ×
    • Create New...