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Old 13th July 2017, 12:09 AM   #1
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Default Bouncing Ball Wave

Hi Guys
If you type that thread title into Google images, you get plenty of examples describing bouncing ball movement,
but I’d like to know what a ball bouncing up and down on the same spot looks like.

Are there any examples of that?
I’m after 180 degrees of amplitude data essentially so a program could simulate
a convincing bouncing ball on a 2D screen that never loses energy.

I’m just not sure if that will look sinusoidal or actually circular.
Cheers, Brek.
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Old 13th July 2017, 12:52 AM   #2
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it wont be sinusoidal, the top half of the wave will look roughly sinusoidal. The bottom half will be "pointy"

This might help

http://www.real-world-physics-proble...l-physics.html
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Old 13th July 2017, 1:04 AM   #3
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hi
Admittedly, I havenít even given thought to what happens to the ball itself.
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Old 13th July 2017, 1:05 AM   #4
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Given the basket ball image example on that page,
I should be able to try just the peak part from a sin lookup table.
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Old 13th July 2017, 1:12 AM   #5
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I only skimmed that page, I was only thinking about the path the ball would follow, not the deformation of the ball.

A simpler way to describe it would be as a positive rectified sine wave, that shouldn't be too hard to plot. I don't think that is the path a bouncing ball would actually follow but it would look close enough.
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Old 13th July 2017, 8:45 PM   #6
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Kind of ... sort of I think it could be better but not sure why.
Maybe the downward acceleration should be greater.
https://www.youtube.com/watch?v=zWXe18iCvpM
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Old 14th July 2017, 3:13 AM   #7
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Ok, Iím happy with this one
https://www.youtube.com/watch?v=-P8oZkYYvCY
It has a linear component that would end up making the ramp steeper,
as if cut from the peaks of a sine, and then the empty space trimmed out.

Basically the index for the sine table is divided by a number,
and the result added to the lookup value of the sine table.
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