Animating a rolling ball

qbfiji

Hi everyone.

I'm trying to animate a rolling ball but I can't figure out how to make it slow down as it comes to a rest. I'm sure there is a very obvious solution to this that I'm just not seeing. I downloaded a golf ball from the Daz store and am trying to make it bounce and roll to a stop.

Any help would be greatly appreciated.

Cheers.

Jaderail

I'm not 100% sure this will work but it came to my mind to try it this way.

At the point you wish it to start slowing down Create a new KeyFrame on the DS Timeline and Slow the revolutions (roll) a bit for some distance. Then create another KeyFrame and Repeat this again. I picture a Timeline with keys that get closer and closer together until the stop. Sort of like this...

Start the slow down +--------------+---------+-----+---+--+-+ End of roll. I hope you can see the Idea with the Plus as a KeyFrame and dashes as time distance and frames.

carolinebegbie

I find this easier to do visually using the graph editor in aniMate2. (or graphMate) This is exactly what Jaderail said, but more visual, because you can see the keyframes in the right place on the animated channel.

By channel, I mean, if you are animating the ball along the X axis, then the channel would be the X Translate channel.

If you have aniMate2, you can create an aniBlock, go into the graph editor (see the aniMate2 manual at
http://www.gofigure3d.com/site/index.php?option=com_content&view=article&id=54&Itemid=56

The first image is a screen shot of aniMate2, with the ball slowing down along the X axis. The higher up the line goes, the further to the right the ball is. You can see the keyframes. When the ball is a constant speed at the beginning, there are no keyframes, but as the ball slows down, there are more keyframes to gently slope the line, so that the deceleration along the X axis happens.

The second image is a screen shot of graphMate, after I baked the aniBlock. Unfortunately baking creates a key on every frame, but you can see how at the beginning that the line is steeper, meaning that the ball moves further to the right in a shorter amount of time.

Victor Navone, who works at Pixar, and created the first viral video describes it better:
http://www.navone.org/HTML/Tutorial_Splines1.htm

(Victor's Alien Song video is here: http://www.youtube.com/watch?v=duOoqDu2H70. As a matter of interest, this was created in Animation:Master, which is still available.)

Jaderail

Great Tip, Thank you for that.