This free prop works has a free Python Script to go with it. Please visit my Git Hub repo: https://github.com/DataJuggler/PythonScripts And download the file called Newton's Cradle.py. The easy way to download this is click on the file, then click the Raw button. On your keyboard hit Control + A to select all followed by Control + C to copy. Paste the contents of your clipboard to your favorite text editor (Notepad or I use Visual Studio). Set the timeline in IClone to the frame you wish to start the perpetual motion, and run the Python script. Click the 'Rotate Spheres' button to create the animations.