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holeycow
02-09-2016, 04:40 AM
I've got a job to do where I need to make individual wheels go around an existing model of a racetrack.

It seemed to me that bullet dynamics would be the most realistic way to do it so that the wheels follow with the contours of the track.

All is going really well until I try to set up the steering... it's left me pulling hair out all day. I tried using a parent object, keyframed with the dynamics turned off, but that did nothing, and I've found nothing in the way of documentation or tutorials that explains how to do it, although I've seen plenty of videos people have posted where they obviously got it working.

I guess I'm just not looking in the right places.

Does anyone have any suggestions?

Any help would be greatly appreciated.

MonroePoteet
02-09-2016, 11:21 AM
I think in LW 2015, the Bullet Constraints are the way to go, but I haven't played with them. Here's a car rig setup video, which stops short of showing the steering:

https://www.youtube.com/watch?v=b9Uqs0_SVrE

You might also have a bit of luck by re-loading a second instance of the wheel geometry (don't Clone it, or Bullet will be cloned as well), parenting the second instance of the geometry to the Bullet-controlled geometry with Parent In Placed turned OFF, and then use the Motion Panel=>Controllers and Limits tab to set the second instance's rotation in H,P and B to be "Align to Path".

Good luck!

mTp

P.S. Forgot to mention: you'll need to Hide and deactivate the original, Bullet-controlled geometry in the Scene editor so that only the align-to-path child appears in Layout and in the animation.

MonroePoteet
02-09-2016, 11:34 AM
Nevermind. A little more experimenting shows the child Align-to-path merely duplicates the Bullet motion. Sorry!

mTp

holeycow
02-09-2016, 12:14 PM
Nevermind. A little more experimenting shows the child Align-to-path merely duplicates the Bullet motion. Sorry!

mTp

Thanks anyway... I very much appreciate the suggestion. I know there has to some way of doing it, just a shame that it doesn't seem to be covered in the documentation... unless I've missed something.

holeycow
02-09-2016, 04:36 PM
I finally got my head around it after a good night's sleep. Using the 6Dof constraint instead of the hinge gives you motors on all rotation axis. It's a pretty painful way to do it, but it seems to be working.

spherical
02-09-2016, 04:47 PM
There's a thread on the forum that goes into detail about how to do this. Was a while ago. IIRC, it had to do with not only steering by following a spline, but wheel rotation as well. Might try a search on those terms.

holeycow
02-10-2016, 03:56 AM
Thanks Sperical....looking into it. I thought I had it sussed.....but then it fell apart big time