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Re(2): What I really need here Posted on March 21, 2024 at 04:16:14 PM by Craig G
Better hold off on that Paypal transaction. This challenge is huge.
Even if you had a certified physicist working on it, he would still have his work cut out.
Here is an interesting Sports Ballistics study where the author even included jai-alai in the mix.
Anyway, I am a big believe in a 'chronophotography' approach, which avoids a lot of the uncertainties of radar guns. I can imagine a 3 or more 120 fps cameras being more than adequate to handles the problems of perspective-based. distortion. An example of that distortion would be at Magic City, where viewed from straight on, the side wall panels appear to be square, but when you look at the area of the 12-13 lines from the front camera view, those panels look more like 4 x 8's.
As things stand with the Youtube videos, it is possible to determine the throw and catch positions withing about 1/4 of a line marker, and get the frame number accurate to within 1 unit. If the camera shows when the ball hits the front wall, you can also get the point of contact off by no more than one frame.
An example of that would be looking at a serve at Dania from 10.8 coming out to 13.3. I found the avg speed to the wall at 78 mph, and from the wall more like 38 mph.
Since the number of people interested in this is probably about 1.5 or so, it isn't worth the tedious labor. However, I would like to at least determine some basic elements.
Like average speed at the moment the serve is caught, avg time between serve thrown and caught, and so on. Depending on what the videos give us, we might be able to see the typical pelota speed when it is caught in the front part of the courts.
As I said in the other post, to objectively compare the speeds of the two frontons is complicated. In singles, each point will have a receiving-the-serve part, which is looking like about 22 mph.
Step 1 would be to verify if that is the same in both places.
Step 2 might be to work out the singles rebo % for each fronton, which is important because at MC, that will make the time from throw to catch at over 4 seconds.
Step 3 might be to get the composition of shots that are caught up front.
Also, as you mentioned, the speeds we are using are for horizontal travel, but the actual path is more parabolic. We can move a bit closer to getting the actual pelota speed by computing the hypotenuse of a right triangle based on the height at the point of contact with the front wall. It might work out that some multiplier of (hypotenuse - base) would be close enough to the truth.
What I would like the most would be the 120 fps data from a camera towards the front. Then we could nail the degree to which the front wall collision affects the pelota speed.
That's about it. I will probably chip away at this here and there. If for no other reason than my own curiosity.
If you can think of any other observations that might be gleaned from the existing video format, let me know.
Replies:
Dania size - By TigerMarch 14, 2024 at 11:21:25 AM
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