Car Wheel rotation

Car Wheel rotation

Anonymous
Not applicable
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Message 1 of 3

Car Wheel rotation

Anonymous
Not applicable

Hi guys, 

I have a question, why the wheel when translate in the negative axes like -90 Y, start to works in the opposite way than the vehicle direction? I used this expression to animate the wheels: 

L_F_Tire.rotateX = Root_CTRL.translateZ + Root_CTRL.translateX;

L_B_Tire.rotateX = Root_CTRL.translateZ + Root_CTRL.translateX;

R_F_Tire.rotateX = Root_CTRL.translateZ + Root_CTRL.translateX;

R_B_Tire.rotateX = Root_CTRL.translateZ + Root_CTRL.translateX;

 

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Accepted solutions (1)
1,611 Views
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  • rig
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Message 2 of 3

mcw0
Advisor
Advisor

Rotation should not be driven by an explicit translation channel.  It should be a function of distance.

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Message 3 of 3

mcw0
Advisor
Advisor
Accepted solution

Sorry for the short answer.  Something came up.  Here's a better explanation.  You want to measure the distance traveled.  Usually, a curve is used as you can get the arclength of the curve at any point along the curve.  Divide that by the circumference of your wheel and then multiply by 360.  That's the quick and dirty way to do wheels.

 

The optimal way would be to add incremental rotation frame by frame.  This approach allows you to do burnouts and to accelerate and decelerate.  The first method will have very apparent issues if you change your speed.

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