Assignment #1: Bouncing Ball Basics

Assigned: Tuesday, October 1st, 2019
Due: Monday, October 7th @ 9:00 PM


Part 1: Light vs. Heavy Ball Sketches

On one sheet of paper, sketch out the poses of two different balls bouncing with forward momentum: a light ping pong ball and a heavy bowling ball. The two different drawings should not overlap, but should drawn side-by-side or above-and-below so they can be compared.
Draw enough frames such that we can see the balls roll to a stop. Pay close attention the the spacing! When it slows down, the spacing decreases. When it speeds up, the spacing increases!

Assuming 24 frames per second, draw a pose every two frames. This is called animating on "2s". For each second of time that passes with this animation, you will see 12 drawings.
You'll need to emphasize the contrast between the different weights. Pay close attention to these principles:

  1. Timing. How does the rhythm of the ping pong ball bounces differ from the rhythm of the bowling ball bounces? Observe how these objects behave in reality. There are several ping pong balls available in the lab. Bowling balls are slightly harder to come by (if not a bit rough on the flooring), so check out video reference on the web. Here's one example.

  2. Spacing. When does the ball speed up? When does it slow down? This will also affect when squashing and stretching happens. Overlap drawings to signify deceleration and space them out for acceleration.

  3. Arcs. Arcs are included in every aspect of motion, as they make animation more fluid and natural. Balls naturally bounce in arcs! You should sketch the motion arc for each ball before drawing the poses.

  4. Squash and stretch. Keep in mind that you are animating a "normal" bouncing ball that doesn't have a mind of its own. Squash and stretch that is too extreme and that spans too many frames will make it look like the ball is willing itself to jump, and that's not what we want to see. A note for the future: you generally shouldn't see squash and stretch when your animation plays at full speed, but you should be able to feel it.

After you have finished your sketches scan them in, or take a straight-on photo where everything is clear. Check out this scanning tutorial to learn how to do this. Save your scan as bb_planning_sheet.jpg.

Part 2: Animation in Maya

Animate a light ping pong ball and a heavy bowling ball bouncing side-by-side in 3D using Maya. Go through the 3D ball animation tutorial to accomplish this. The heavy ball should bounce and roll to a stop, but the light ball only needs to bounce while the heavy ball is still moving (with a minimum of three or four bounces).

Turn in both the Maya and AVI files specified under Part 2A and Part 2B.

Turn-in Checklist

You will be turning your files into Canvas. Below is a check list of what you will be turning in and what those documents should be named:

Part 1

Part 2