Throwing and catching always amaze me. And it’s not something that everyone is always great at, for sure, but anyone can try to toss a wad of paper into the waste basket. Whether or not you make it, the calculations under the hood, happening so quickly, always astound me to think about.
What’s amazing is our ability to calculate the path of something in the air.
There’s a test they did with Cristiano Ronaldo where someone kicked a ball to him so he could head it. They shut off the lights before the ball was in the air and somehow from the body shape of the person kicking it, he was able to know how to make contact with it without being able to see it.
Pretty impressive. I think they’re underestimating/ignoring the input from hearing, especially with the second one where he probably (subconsciously, of course) heard the ball bounce near his foot. Plus the subtle changes in air pressure around his legs to tell where the ball is, etc.
Cool video, thanks.
Edit: Still watching as they’re analyzing his free kick. Cool shit. The human body is wild.
One thing I don’t really see people talk about is how Ronaldo (and other soccer/football players) use their opposing leg to kind of hop up and dissipate any energy that they didn’t transfer into the ball. Fucking cool. You don’t even realize it’s happening.
I haven’t seen any videos on it, but I remember doing kinematics problems in school involving baseball pitchers and how they throw, and it is actually insane. Each joint and section of the pitcher’s arm is like perfectly timed to provide the most velocity to the projectile. So you add up the momentum from the swinging shoulder to the momentum from the elbow to the momentum from the wrist, to the momentum and spin from the fingertips. Baseball is boring as shit, but the physics behind pitching is cool af.
I remember when I was younger and would lay on my back throwing a baseball up in the air and catching it, that I could watch it go up and not follow it with my eyes as it goes down and still have my hand in the right spot to catch it
Read somewhere that catching is actually dead simple, just “move towards the image of the incoming target” (I’m not talking about the arm kinematics).
There were a robot paper bin that zoomed under stuff you threw up in the air using no complicated algorithms for example.
Funnily many algos are calked on physical and chemical effects in the real workld, like splines for example were made with a thin metal bar and lead weight bending it to get the lines used in boat hull construction.
I mean, that’s easy enough if you’re trying to catch the ball with your face. Usually that’s not the goal, so you’ll be standing slightly to the side or the object is moving toward your stomach. ;)
Even then, that’s discounting the whole image analysis part of the equation, which your brain does dozens of times per second with incredible accuracy. Your waste bin example would have had to do enough to differentiate the ball from the background, and that definitely qualifies as a complex algorithm.
ETA: also, closing your hand at the right time does require your brain to know how close the object is, not just that you’ve positioned yourself in its path.
![[Thread] Mental Math](https://mander.xyz/pictrs/image/4a605b7b-7272-471f-ac11-37366ac7d8bd.png){kind=link}
Throwing and catching always amaze me. And it’s not something that everyone is always great at, for sure, but anyone can try to toss a wad of paper into the waste basket. Whether or not you make it, the calculations under the hood, happening so quickly, always astound me to think about.
What’s amazing is our ability to calculate the path of something in the air.
There’s a test they did with Cristiano Ronaldo where someone kicked a ball to him so he could head it. They shut off the lights before the ball was in the air and somehow from the body shape of the person kicking it, he was able to know how to make contact with it without being able to see it.
https://youtu.be/0k2ey_okQ4E?t=1255
Pretty impressive. I think they’re underestimating/ignoring the input from hearing, especially with the second one where he probably (subconsciously, of course) heard the ball bounce near his foot. Plus the subtle changes in air pressure around his legs to tell where the ball is, etc.
Cool video, thanks.
Edit: Still watching as they’re analyzing his free kick. Cool shit. The human body is wild.
One thing I don’t really see people talk about is how Ronaldo (and other soccer/football players) use their opposing leg to kind of hop up and dissipate any energy that they didn’t transfer into the ball. Fucking cool. You don’t even realize it’s happening.
I haven’t seen any videos on it, but I remember doing kinematics problems in school involving baseball pitchers and how they throw, and it is actually insane. Each joint and section of the pitcher’s arm is like perfectly timed to provide the most velocity to the projectile. So you add up the momentum from the swinging shoulder to the momentum from the elbow to the momentum from the wrist, to the momentum and spin from the fingertips. Baseball is boring as shit, but the physics behind pitching is cool af.
I’m not a fan of Ronaldo but that was very cool to watch, thanks for sharing!
I remember when I was younger and would lay on my back throwing a baseball up in the air and catching it, that I could watch it go up and not follow it with my eyes as it goes down and still have my hand in the right spot to catch it
Read somewhere that catching is actually dead simple, just “move towards the image of the incoming target” (I’m not talking about the arm kinematics).
There were a robot paper bin that zoomed under stuff you threw up in the air using no complicated algorithms for example.
Funnily many algos are calked on physical and chemical effects in the real workld, like splines for example were made with a thin metal bar and lead weight bending it to get the lines used in boat hull construction.
I mean… there is nothing simple about the calculations involved in something like that lol. That’s like countless differential equations per second.
No, IIRC it was just : film the ball and repetedly do: “is the ball to the left, go left. Is it a little to the left, go little to the left” etc.
Like a PID but with only the P part. I don’t know if it makes any sense :-)
I mean, that’s easy enough if you’re trying to catch the ball with your face. Usually that’s not the goal, so you’ll be standing slightly to the side or the object is moving toward your stomach. ;)
Even then, that’s discounting the whole image analysis part of the equation, which your brain does dozens of times per second with incredible accuracy. Your waste bin example would have had to do enough to differentiate the ball from the background, and that definitely qualifies as a complex algorithm.
ETA: also, closing your hand at the right time does require your brain to know how close the object is, not just that you’ve positioned yourself in its path.
IIRC the imaging was just a black & white camera with the ball being black.
Detecting what is a ball is of course a whole other game, that I think was not the question. But if was then yes, that is more complicated.