Exhaust tracking Problem

Hey all, I’m experimenting with some “Track To” options, and having a problem.

I have a jet exhaust.


And I have all the collapsing panels all targeted at an empty which, when I raise a lower it, cause the panels to open and close.

You can see what I’mt alking about in…


The first shows what it’s supposed to do but as the second shot shows, once I rotate the base, all of the panels try to orient themselves to still be facing “up”. This isn’t good.

Does anyone know a way to fix that? Is there some box I should check? It just wont work for the animation.

And while I’m at it, does anyone know of a better way to achieve this effect? Like, without having to target an empty?

Thanks, folks.

Ooh, ouch. The problem with track-to is that it always tries to use global z as a reference point. This is lame and bad, and fails at many things.

Hey, though… the new ‘Locked Track’ constraint in the CVS might actually work, I think. You just pick one axis to track-to (local x or y I’d guess, here) and it constrains all tracking rotation to just that, so if your empty is parented to your exhaust and is just going to move up and down (in and out) you shouldn’t have any problems.

the New RC2 has a align target button in the track to constraint which will target the z axis and not the world z axis

Hey! It worked! It totally worked. I switched all the panels to 'Locked track", (along with all the little piston things) and it worked!

Thanks a ton, folks. I’ll try to post a finished thing I’ve I have it.

By the way, you’re a fantastic mechanical modeler. SBFP is great.

Hey, thanks BlackBoe!

Here’s kinda what it’s a part off: http://i10.photobucket.com/albums/a136/Mrdodobird/jetenginelight.jpg

The materials are temporary (I just grabbed them from a different project), but I dig it.

Here’s a test animation (not timed or anything) http://www.robotsoup.com/extra/Unfoldrocket.mov

Thanks again for your help, dudes.

No helpful comments here, but just wanted to say that’s looking really nice! Could do with a bump map though :slight_smile:

You’re a genius in this kind of modeling & animation stuff Mrdodobird…

I know. That’s great. Once again, you’re a fantastic mechanical modeler and animator.