Dwell Time .....

[blahness]

My problem with a lot of what brokenball tries to say is that he is always trying to simplify the problem to high school mathematics when the actual system is far more complex (and there are plenty of actual peer reviewed papers by zeio which show these complexities). That's why his math never works - he still thinks as long as your racket tangential speed is fast enough you can make the ball spin at Xu Xin levels regardless of whether you're using boosted Hurricane or sandpaper. We know that to be untrue - and he still insists on his theory lol.

As an actual practising engineer who designs complex structures - this is why I doubt all of his qualifications tbh, or maybe he only works with simple systems all his life. Either way, real engineers who work with complex systems typically don't function like brokenball trying to simplify everything complex and not even respecting results in reality, otherwise you'll see a lot more actual failures in the world.

 

[dingyibvs]

My problem with a lot of what brokenball tries to say is that he is always trying to simplify the problem to high school mathematics when the actual system is far more complex (and there are plenty of actual peer reviewed papers by zeio which show these complexities). That's why his math never works - he still thinks as long as your racket tangential speed is fast enough you can make the ball spin at Xu Xin levels regardless of whether you're using boosted Hurricane or sandpaper. We know that to be untrue - and he still insists on his theory lol.

As an actual practising engineer who designs complex structures - this is why I doubt all of his qualifications tbh, or maybe he only works with simple systems all his life. Either way, real engineers who work with complex systems typically don't function like brokenball trying to simplify everything complex and not even respecting results in reality, otherwise you'll see a lot more actual failures in the world.

I think he's right to point out some myths in TT using his higher level of knowledge, but he's conflating knowing more with knowing everything, and reaching firm conclusions without accounting for the possibility of more variables.

For example, I once saw Fang Bo teaching people to use the leading edge of the racket to brush the ball during service, and he said it was because there was more rubber between the leading edge and the trailing edge for the ball to roll on. That's obviously absurdly false, and it would be right to point that out. What would not be right to say is that because the rubber is the same at both edges that you can serve with either edge and generate the same amount of spin. That's empirically false, and failing to explain it with one's knowledge does not negate its veracity. I'm not saying that he said this, but this would be an example of the type of things he does.

 

[dingyibvs]

What flaws? The video is of my toxic 5 hard bat. It isn't meant for looping. I posted it because Atlas Newton requested it.

Flaws in demonstrating dwell time. Not saying that was your intention, just saying that it doesn't help answering relevant questions, such as...

Yes, so how does dwell time help with loops?

...this question. I don't know the answer. Why does what we feel as "dwell time" help with loops? I'd like to know.

When brushing, much of the energy goes into spin, not speed. You need to be superman to get both. It is a trade off.

Sure, but it could change actual dwell time vs a hit, no? Maybe, maybe not, you're a scientist, it'd be nice to have both a theoretical explanation as well as empirical answer. Unless you have both, you probably shouldn't speak in definitives.

This is BS. If the paddle is still accelerating then it hasn't reached maximum speed. Also, any accelerating after contact simply increases recovery time.

Right, the paddle doesn't reach maximum speed until after contact. This is what we try to do, it is also an observed phenomenon based on studies zeio posted.

Yes accelerating past contact will increase recovery time, which is why we try to stop accelerating as soon as humanly possible after contact.

Who said it was going 70 mph? The ball was shot from a Newgy 2050 with a speed of 10 which according to Newgy, should be about 10 m/s. Due to age I think it was going slow but the speed can be estimated by looking at how many frames it takes for the image to move one TT ball.

I didn't say it's going 70 kph, I specifically said that it isn't, which makes it less useful because real TT loops go at 70+kph.

Yes maybe, but that is not what I was trying to show.

But that's what you should show. You're showing tiny parts of the question re: dwell time, which is not sufficient to answer the question we're actually interested in: what is this perception we call dwell time, and how does it help us to loop?

I do have video of the Newgy shooting balls at my Firewall+ with T25 on the FH. The Newgy is shooting balls at a speed of 10 again. This time I am holding and swinging the paddle. The contact time is still on 2-3 frames at 2000 fps. It is hard to tell if the rubber is still in contact with the ball for 3 frames.

Great, that's a good start. Now compare it to a setup with less perceived dwell time, such as say a Yinhe T11. Then compare strokes that change perceived dwell time as well, e.g. a loop where you're at constant or decelerating speed vs a stroke that accelerates through the contact at the same speed. Does the actual dwell time change? If it does then what surrogate markers are we using to perceive it since there's no way we can tell the difference between milliseconds or fractions of them?