How to animate (move not rotate) an object in a circular motion.

[John Cuevas]

Generally, I would make a null object, parent what I want to rotate in a cicle to that null and just rotate the center null.

But if parenting is out here’s another method, create a comp sized solid and using the circular mask tool, make a mask the size you want your object to move around(circumference). Open up the mask properties, click/highlight “Mask Path” and copy the path(cntl+c). Now open the position property of the object you want to move along that path, click/highlight “Position” and paste(cntl+v).

The resulting keyframes are roving keyframes, meaning the first and last keyframes are the anchors. You can slide either one and the rest will auto adjust. If you want to change them, just highlight all, right click and deselect “rove across time”

Also there are methods using expressions that can also create circles—not sure if you need that type of control though.

Johnny Cuevas, Editor
Thinkck.com

“I have not failed 700 times. I have succeeded in proving that those 700 ways will not work. When I have eliminated the ways that will not work, I will find the way that will work.”
—THOMAS EDISON on inventing the light bulb.

[Walter Soyka]

[Daniel Taylor] “I want to be able to move a Null Object around in a circular motion. The only way I can think of doing it is to move the anchor point and rotate it. However, this isn’t what I need because I cannot parent another object to the Null to mimic it’s movement if it’s only altering the rotation. “

Create two null objects at the same position. Call one ROTATOR and call the other something else (POINT maybe). Parent POINT to ROTATOR, then slide POINT away from ROTATOR on one axis.

Rotate ROTATOR. Then POINT will move around it in a circular motion, but as you note, it also rotates. Fix this with an expression applied to POINT to offset ROTATOR’s rotation:

-thisComp.Layer("ROTATOR").transform.rotation

Now you can parent anything you like to POINT and it will follow the circular motion of ROTATOR’s rotation.

Walter Soyka
Principal & Designer at Keen Live
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
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[Daniel Waldron]

You could create a circle mask on your Null (hold Shift+cmd for a perfect circle), Open the mask options by double-tapping “m” and copy the mask path. Paste this to your Null’s position. Add a loop expression (or copy and paste the keyframes) if you need to make it go around more than once.