In this display, go to the Real Space view and drag the pendulum to any starting position you choose holding down the mouse button while moving the mouse. Then you may select a different view if you want and click on action to start the pendulum swinging. You will notice that if you start the pendulum in the right half of the screen, the kicks are delivered at the top of the swing. If you start the pendulum in the left half of the screen the kicks are delivered at the bottom of the swing.