# Newton and time

Hi,

I used a damper to ‘fade’ from one set of settings to another, but it doesn’t behave the way I like it. A LinearFilter is also not the movement I am looking for.

Now the Newton or DeNiro filter creates a nice transition from one value to another, but I don’t know what the relation between the acceleration and the result is.

I would like to be able to use TIME as an input, and to calculate the acceleration from it automatically, but I don’t really have a clue how they are related, since I don’t know what ‘acceleration’ is measured in. Is it 1/s*s?
And how does acceleration evolve? Linearly from 0 to 1 to 0 to -1 to 0 again? Or is it a sinus? Something else?

Anyway if someone can help me to create the math to find the right acceleration value for a given time value, I would be most grateful.

hello, i would turn the problem around: take a linear filter with a fixed time setting, and use a Tweener to adjuste the dynamics of the curve. as the tweener works on a fixed interval of 0…1 you will probably need an InputMorph to interpolate between your settings, using the output of the Tweener.

I did some experimenting, and using:

4 / (TIME * TIME)

as the acceleration parameter, it seems to work for 1 second as well as for 60 seconds. Good enough for me.