1
$\begingroup$

Blender file

Just a bunch of cubes and one single bone, with the custom property and the driver.

https://gfycat.com/coldablecowbird

So I've trying to work this a driver to control the rotation speed, to make the animation easier, and there seem to be an issue there: The model seems to exponentially speed up after the first keyframe, then slow down right before the second keyframe, and maintain constant speed. I'm pretty sure it's an issue with the way I made the driver, although I'm not sure how to fix it. Any ideas about what I can do?

$\endgroup$
1
  • $\begingroup$ Hello and welcome. While files, images, and external videos or links may be helpful additions they should not be the only way to obtain information about your issue. Don't make understanding your question rely on downloading a file, watching a video or visiting an external site. Use the builtin tools to upload images or gifs, along with thoroughly explaining the problem in written form so it can be indexed and searched for thus helping future visitors with similar issues. $\endgroup$ Commented Mar 17, 2022 at 17:20

1 Answer 1

1
$\begingroup$

you have the wrong formula -> use this as formula, so you got constant speed.

It has nothing to do with interpolation.

enter image description here

You can change your custom property so that it allows higher values here: (your max value was 1, so that's why you couldn't make it quicker and i think that's why you tried to solve this with multiplying another value)

enter image description here

after you changed the maximum value of your speed, you can change the speed in the graph editor by selecting that point, then G and move your mouse up like this:

enter image description here

--- UPDATE:

to "automate" the rotation, delete the keyframes for speed and enter "#frame/10" into the speed value.

blend file to check out:

$\endgroup$
7
  • $\begingroup$ I want the driver to automate the spinning. That's why I have the "var*time" expression. By removing the time factor, that means I need to manually spin the model, so the driver really doesn't do anything, right? I can just animate the both itself, without any limitation to the rotation. Am I getting right? $\endgroup$
    – Yogev
    Commented Mar 17, 2022 at 15:51
  • $\begingroup$ can you please elaborate a bit more what your "end goal" is? What do you mean by "automate"? you mean it should rotate when the animation starts? just set "#frame/10" into your speed value. Then this would do it. of course first delete the keyframes in your speed value. $\endgroup$
    – Chris
    Commented Mar 17, 2022 at 15:54
  • $\begingroup$ i updated my answer and added the blend file, so you can check it out $\endgroup$
    – Chris
    Commented Mar 17, 2022 at 15:57
  • $\begingroup$ The end goal is to be able to control the rotation speed for easier animation. I want to have a gradual build up of the speed and then let the object rotate at the constant top speed. I have this aircraft the I try to rig. Is has a a minigun-like weapon. I want it to rotate gradually until it get to the top speed, stay there for a few second (while there is the shooting animation), and then slow down to a dead stop when the action is done. $\endgroup$
    – Yogev
    Commented Mar 17, 2022 at 15:59
  • $\begingroup$ There are also the propeller blades, that work in the same way. Instead of animating the propeller and the gun for the entire animation sequence, I thought it would be simpler to use driver for it. gfycat.com/shockingzanyindiancow $\endgroup$
    – Yogev
    Commented Mar 17, 2022 at 15:59

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .