Animatable Tire Squash (3dsmax)

multimediaman

Traffic Car Connoisseur
#1
Creating tires that flatten and bulge under the weight of the car is usually something that's overlooked in 3d car animations... But producing this effect is actually not much more complex for animation than it is for still pictures.

1.) First off let's start off as though we were going to fake the look by embedding the tire into the ground some.

The ground plane is intersecting right through the tire...


2.) Now go into the Command Panel and select the Create tab. You'll want Space Warps for the Category, and then choose Geometric/Deformable for the Sub-category. For the Object type, we'll create an FFD(Box). This works pretty much like your average FFD modifier, although any translation of the control points deforms your mesh, there's no way to 'fine-tune' your cage before the control points are 'activated'.

You should create your FFD(Box) something like this:



3.) The box doesn't need any depth segments, so take those out.


Here's a front view of that, but we're about to add some segments in the front.



4.) Change the segments on the tire's front and back side to 6, just for a bit better control in the right areas.

Once you've done that, move the control points as I've shown in this picture:



5.) After that view of the tire is squashed correctly, take the middle four control points and push them out towards the side of the car, to create the bulge that comes with the flattened tire material:




6.) Your final result should look something like this:



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Some side-notes:

First - your FFD(Box) should be linked to the vehicles rig. I highly recommend your vehicle's rig includes a dummy for the tire's suspension height, and steering, which will not rotate during the vehicle's animation... and then a dummy that will actually do the spinning for the tire. Doing it this way, you'd link(child) the FFD(Box) to the dummy which controls the overall orientation of the tire. The Rig schematic would look like:

DUMMY_TireFR_Orientation
|_FFD_TireFrontRight
|_DUMMY_TireFR_Rotate
|_TireFrontRight

And finally, we've got a video to show the end result of this tutorial in motion:

YouTube.com - Animatable Tire Squash Final Result (SMCars tutorial)

I hope you find this tutorial helpful in your 3d projects! :grin: