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gyro
04-30-2007, 12:13 PM
Hi, I could do with a bit of help with constraints. I've got an animation of a multi-link car suspension to do and I can't find a way of linking/constraining the components that give the proper movement of the wheel. I can get part of the way there but I would still have to position other components frame by frame to fit in - not a great way to spend time.

Any suggestions on how to aproach this would be most appreciated. Even ways of faking through would be fine by me, any way to avoid having to manually adjust the position every frame.

I don't think I can do it with the existing constraints so I might try to do something with Expressionist, although I've never tried anything so complex before. So any pointers on this approach would be good too!

The image attached shows the basic component layout I'm dealing with: A small block (car wheel) is linked to the larger block (car body) by four rods. All the rods are at different angles and lengths so when the small block moves it will also be forced to rotate by the links.

Cheers
DaveW
cjberg
04-30-2007, 01:59 PM
There have been a number of tutorials about making cars, check electro303: http://www.paralumino.com/electro303/electro303/02-tech/tech_adv-p01.html

There are also other techniques, but it depends on what you want... take a look at the car tutorials on this site and see if they help.

Cj
DanielH
05-03-2007, 07:35 AM
I think Xpressionist is what you should go for in this case. That is judging from your description.
Jens C. Möller
05-03-2007, 08:47 AM
I would suggest you to just link the wheel to the car body and animate it relative to the car body and use IK chains for the rods. That is at least how I did it when I did this:

http://www.jcm-animation.de/downloads/demo/JCM_Touareg.mov

Jens
gdogfunk
05-03-2007, 05:57 PM
WOW! Jens, that is incredible!!! You have done it again! I really like how the wheel keeps spinning when it's off the ground. Is that all automated or did you hand key some of the wheel rotations?

Great work!

Ryan
Jens C. Möller
05-03-2007, 09:06 PM
To be honest I cheated with Reel Motion... So I had help with the animation. But the basic setup should also work with keyframed or scripted motion. Its only the car body and the wheels animated.

The spinning wheel off the ground is actually an error :) since the four wheel drive of the touareg would prevent exactly this. But this part of the sequence belongs to my tests... my client would have never let me go with this.

:)

Jens
AVTPro
05-06-2007, 09:13 PM
Vehicular sims are not cheats Jens. :)
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