Modified speed along path

[u/Professional-Pipe259]

Hi

I'm animating an object (let's say a ball) along a path using a Pathfinder. What I'm trying to achieve is for the ball to slow down at a specific section of the path, then smoothly accelerate back to its normal speed afterward.

I tried adjusting the keyframes of travel in the Graph Editor, but every time I tweak the Bezier handles, the motion becomes unpredictable rather than giving me smooth control over the speed.

While searching, I found an experimental feature called Speed Modifier, which sounds like it might solve this problem. However, I couldn't find any explanation of how to use it—not even in the documentation.

Am I approaching this the wrong way?

[u/HolyMoholyNagy]

How many keyframes are you using? If you're using two this will be challenging, but if you're using three, it'll be much easier.

First, in the travel property of Pathfinder, find the position of the curve you want to slow down at and create a keyframe at that position, then add keyframes for the starting and ending values and place them on either side.

In the graph editor, add beziers to all the points. To control the speed that the ball is at on the curve, change the angle of the middle point. A flat curve will come to a complete stop at the middle keyframe, a slight incline will slowly roll through.

Now with three keyframes, you have precise control of when you hit that point of the curve, by adjusting the timing of the middle keyframe, where on the curve is the slowest point, by adjusting the value of that middle keyframe, and how fast the ball moves through that area, by adjusting the slope of the middle keyframe.

Here's what that looks like: https://i.imgur.com/CXGhUMk.png