Position & Rotation

Adding a Group and a simple expression that divides 360º by the number of copies in the Repeater will allow you to offset the position of the original ellipse, add copies that fill the circle, and then rotate the entire array. If you want the copies to grow from the original, do the rotation math first and then animate the number of copies. 

You can see all of the modified properties.

Here is the workflow:

1. Press the "q" key until you get the ellipse tool, double click to create an ellipse with all properties at the default values
2. Adjust the size, fill, and stroke of the ellipse
3. Use the Add button to add a Group to the shape layer and slide the Ellipse into the Group
4. Select the Ellipse and add a repeater, and set the Position to 0,0 then add the following expression for Repeater/Rotation

   c = content("Group 1").content("Ellipse 1").content("Repeater 1").copies;
   360/c;​

5. Offset the Ellipse/Position to move the first circle to the desired radius for your graphic
6. Set the number of copies
7. Fiddle with the rotation angle and other values to animate the number of copies, position, and rotation as needed to create your animated graphic

That should get you started. Animation is always about properly linking the elements and their controls, layers, anchor points, positions, and keyframes, even if you use an app that uses nodes instead of layers. 

Hey Maha,

Thanks for the post. I apologize that I do not understand the problem you are having. Can you explain your issue in more detail. I downloaded your project and the shape layer appears to be functioning as expected. I like this comp, though. It can make some unique geometric patterns. Let the community know.

Thanks,
Kevin