Two Balls and a Sack

So there are two very important principles in animation that if you understand them and can execute them well then you can pretty much animate anything.  These principles are bounce and delay.  We were taught these principles through some basic animations.  For bounce, we were given the task of animating (in 2D and 3D) a soft, squishy ball bouncing and a hard, dense ball bouncing.  Below are my examples (first in 2D then 3D).


Soft Ball

Hard Ball

(forgive the crappy quality of this video. They got new camera's at school to capture our 2D animations and they pretty much suck)

If you notice in the ball bounces we employ the concepts of "squash and stretch".  Basically when the ball hits the ground it will squash and when it lifts off (or falls) it will stretch.  This is to show the force(s) acting upon an object. In this case the stretch is caused by gravity/momentum and the squash by the floor.  The more you emphasize this the more cartoony your animation will be.  Also, it is important to know just how much a ball should squash or stretch.  The harder ball hardly has any squash or stretch because since it is denser it won't be affected as much by these forces.

The next important principle is delay.  This is when parts of an object that are being pulled move in wave-like patterns.  It is probably best shown in this animation of a tail.




The tail is made up of 3 "bones". Each bone is being pulled by the one before it. What causes the tail to move naturally is that the second tail is delayed by X number of frames from the movement of the first and the third is being delayed 2X frames.

Apart from tails this delay method is extremely important when dealing with the human body. The legs, the arms, the neck and head all follow this delay principle. When an arm reaches for something the different bones of the arm do not move in unison, but a wave goes through the body/shoulder to the elbow, to the wrist, to the fingers as the arm becomes stretched. If you want to see how this works you can put one of your arms down to your side then reach for something. This wave should be very subtle but its there.


Putting both of these principles to use, you can pretty much animate anything.  We used it to make something jump - a sack of flour to be more precise.

The 2D animation assignment was to make this flour sack jump from one end to another. I decided to make it a little more interesting by adding facial movements plus a flip.

This is my 3D version of this jump (minus flip and face)

This next one is my final in which we were supposed to have the flour sack jump from a platform and then off a diving board. I wanted to do something a little tougher and more exciting.

We weren't taught any principles of character animation nor walk cycles in 3D. But I think I did a pretty good job on it.  So yeah in terms of the two principles you can see that these last two animation use the bounce (which includes squash and stretch) within the jump and the delay principle when it comes to the way the body moves and how the ears wiggle as they are pulled around.