# How do I achieve an acceleration of a rotating object on wake and a deceleration of the same object a few seconds later?

Hi everyone, this is my first post here since I’m new to creating watch faces and still learning.

What I am trying to achieve is, when waking the watch, an object rotates around its own axis for like 2 seconds in an accelerating fashion, whereafter it reaches full speed, and is then slowed down till standstill a few seconds later. What I have (tried to) come up with is:

``````((#DWFSS#)+(interpAccel(#DWE#,0,2,10)*#DWFSS#)*(#DWFSS#*5))+((interpDecel(#DWE#,2.5,6,10))*(#DWFSS#))
``````

But this doesn’t seem to do anything. I also came up with this:

``````(interpAccel(#DWE#,0,2,10)*#DWFSS#)
``````

Which actually does what I want at the start, but then abruptly stops without any animation which looks very jarring.

Again, I’m really new to this and maybe anything I’ve said doesn’t make sense at all, but maybe there’s someone who understands what I’m trying to achieve and can help me out.

Thanks!

Edit: Figured it out!

For anyone who might come across this in the future, this is what worked for me:

``````((interpAccel(#DWE#,0,1,5)*360)+(interpDecel(#DWE#,1,7,5))*(wakeRand(0, 360)))
``````
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Excuse me @Selina and Welcome .

You landed running .

I am not quite sure what the wakeRand is for at the end but if you put a seconds rotational in at the end the hand will carry on after is very exciting start .

`((interpAccel(#DWE#,0,1,5)*360)+(interpDecel(#DWE#,1,7,5))*(wakeRand(0, 360)))`

`((interpAccel(#DWE#,0,1,5)*360)+(interpDecel(#DWE#,1,7,5))*#DWFSS#)`

Thanks for this guys, I wanted to have my wheel spin upon wake. So the formula in this watch face for the rotation with a fast spin at wake, and slowing down after that, and then rotating at slow speed is (the start value 252.5 is so that the rim is at the right position I want it to be):

`(252.5+(interpAccel(#DWE#,0,1,5)*240)+(interpDecel(#DWE#,1,7,5)*240)+#DWE#*3)`

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I am not a big fan of interpAccel but sometimes it really works . Well done .

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