So I have a cube shaped rigid body sitting on a flat static collision object.
If I explicitly set the velocity to a constant at each frame, the object slides across the floor. The distance the object moves each frame is slightly less than velocity*frame_duration because of friction. No surprise there.
What I don't understand is how exactly that distance is reduced by the friction, quantitatively.
Let D be the difference between (velocity*time_duration) and the actual distance the object travels per frame (slowed by friction).
My observations (assuming I remember all my experiments correctly):
1. d does not depend on the mass or velocity of the object.
2. d DOES depend on the frame rate, and the gravity vector.
3. If you multiply the coefficient of friction of the object (or the floor) by k, then d is scaled by k.
With bullet's default settings (1/60 hz frame rate), gravity = (0,-1000,0), and both coefficients of friction at 0.5,
the velocity of the object is reduced by about D= 0.0696 per frame.
Is there a simple formula for D?
Thank you so much!
How does friction work quantitatively?
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