Reference Creation for Ball Bounce

For our first small assignment in the Intro to Animation module, we were given the task of creating a bouncing ball animation. The best way to understand the real world physics of a bouncing ball, for example how its mass, velocity, material etc. affects its bounce, is to get personally involved with reference gathering. 

With that being said, myself and a few others got into a group and bounced two different types of balls, and did so with different variables. I recorded the video, Jack dropped the ball and timed how long it took to stop bouncing, Oliver counted the bounces and Josh wrote all those statistics down for later use.

We video recorded them bouncing, as well as took recordings of the number of times they bounced, the way in which their movement started (i.e. throwing soft, hard, or dropping.) and how long it took them to stop bouncing.

Here are the results and explanations:

Tennis Ball Drop:                                             Statistics:

So here is the tennis ball drop. For the drop the ball was simply allowed to just roll off Jack's hand.

*Note that when I say tennis ball for this video and all other videos with the tennis ball, the ball is in fact just an imitation of a tennis ball; it is a bit more 'squishy' and foam like compared to a real tennis ball.

Bounces:  10

Time: 4 seconds

Tennis Ball Soft Throw:

Bounces: 11

Time: 5 seconds

Tennis Ball Medium Throw:

Bounces: 12

Time: 6 seconds

Tennis Ball Hard Throw:

*Note: Ball hits ceiling

Bounces: 15

Time: 8 seconds

Football Soft Throw:

*Note that the football is also just an imitation of an actual football

Bounces: 15

Time: 4.5 seconds

Football Medium Throw:

Bounces: 17

Time: 7 seconds

Football Hard Throw:

*Note: ball hits ceiling

Bounces: 17

Time: 10.2 Seconds

Self referencing conclusion:

Both types of balls bounce according to the initial downward force applied to them, in other words the greater the initial force the more they bounce, and vice versa. The only time this isn't shown to be true is when the ball collides with the ceiling, but of course in doing it loses some of its energy.

The football bounces a greater amount of times than the tennis ball because in ratio to its size it has less mass. So even though it's larger it is also not as heavy, this is because the material that it is made from, as well as the fact it has more air inside.

The material the football is made from allows it to be more flexible and so store more energy on collision with the floor, therefore allowing it to bounce back to a greater height and repeat the action. The tennis ball however is not as flexible, and compared to the football is a lot heavier in terms of mass to size ratio.

Its good practise to note the materials in which objects are made of and that of which they are colliding into. For example the football is smooth but the floor has carpet on it, so when it collides the floor absorbs some of the kinetic energy from the ball. Had the ball also have been 'furry' then it would lose even more energy on collision. 

The opposite would have happened if the floor was made from concrete; the ball would have bounced to an even greater high and more than likely would have increased the amount of bounces it made overall before stopping.