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SplineIK or alternative help

Okay so I've decided to learn some basic rigging. I'm modelling a tank in Max and I was using a script to place the tracks, but decided to rig it myself as each section is made up of 3 pieces which didn't work well with that method.

I've got it rigged up with bones and it moves in the way I want it to using a HI solver. However, obviously I need it to move around a path. I've tried using the SplineIK solver, but that gives the following:

rig.jpg

The treads flip at points. I've tried setting the upnode manually but I can't get the treads to all face inwards.

I also had a little read about using a path constraint, but it required writing a script that was a bit over my head at this point.

How can I rig up my tracks? I feel like I'm really close but so far.

Replies

  • ghaztehschmexeh
    After trying quite a few things, I think I have found the solution. I'll detail it here for anyone who comes across this with the same issue I was having.

    The centre part is set up to have it's pivot in it's centre. This is so it is at a tangent to the path at all times. These are then constrained using a path constraint. To get the side hinges working, the need to appear to have 2 hinging positions. The first hinge is lined up on the centre tread where it should pivot. The pivot point of the hinge was then set here. The hinge was then linked to this tread. A dummy is then placed on the next tread along, where it would pivot around. The hinge then has a lookat constraint applied to it, with the target set at this dummy. This next tread is wired to have it's path position equal to the first tread's plus an offset.

    This results in the treads moving around the path (which you can set allow upside down, unlike the splike IK) to a tangent to the path, with the hinge pivoting correctly.

    Now if only I knew how to set this up with a script, doing this for 80 sections will be a pain :S

    The set up looks like this:

    oh and it's worth noting the hinges are one object.

    solution.jpg
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