Bouncing Ball

Create the Scene

  1. Add a Floor object to your scene.
  2. Add a Sphere to your scene.
  3. Set the Sphere's radius to 50.
  4. Move the Sphere to 0,50,0.
  5. In the coordinate tab of the sphere, twirl open "Freeze Transformations" and choose "Freeze All". This will make our sphere think that 0, 50, 0 is actually 0, 0, 0 which will simplify our keying.

Key your animation

  1. Go to frame 0.
  2. Set the sphere's position to 0, 300, 0.
  3. Add a keyframe by pressing the red record button, or by tapping F9 on your keyboard. This is the high point of our bounce.
  4. Make the following keyframes
    1. Frame: 20, Position: 0, 0, 0
    2. Frame: 30, Position: 0, 150, 0
    3. Frame: 40, Position: 0, 0, 0
    4. Frame: 45, Position: 0, 75, 0
    5. Frame: 50, Position: 0, 0, 0
    6. Frame: 53, Position: 0, 40, 0
    7. Frame: 56, Position: 0, 0, 0
    8. Frame: 58, Position: 0, 15, 0
    9. Frame: 60, Position, 0, 0, 0
  5. Play your animation (you can do this earlier if you like)

Key your animation

  1. Change your layout from Startup to Animation (pull-down is in the upper-right corner of your interface)
  2. Select all of the keys where your object is resting on the floor ( 20, 40, 50, 56, 60 )
  3. Set the length of the handles to 0 (press the L key) to make the motion more sharp at the point of impact.

Suggested Reading

John Lasseter, "Principles of Traditional Animation Applied to 3D Computer Animation" (pdf), Computer Graphics, pp. 35*44, 21:4, July 1987 (SIGGRAPH 87)

Michael Comet, "Character Animation, Principles and Practice" (.zip tutorial)