I’m horrible, help

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A wild guess but does an additional 2.512m/s sound in the ball park?


You have the right idea but you used the diameter of the ball instead of the radius. The radius is 0.02m
10 rev/sec*2*PI *0.02m=1.256 which is half of what you got.
My point is that 1.25 m/s is not that much more and worth the effort especially when the ball is low and must be looped over the net.
 
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You have the right idea but you used the diameter of the ball instead of the radius. The radius is 0.02m
10 rev/sec*2*PI *0.02m=1.256 which is half of what you got.
My point is that 1.25 m/s is not that much more and worth the effort especially when the ball is low and must be looped over the net.
Darn it! I knew something was off… Turns out I’m terrible at maths, that formula was quite basic.
thanks for the physics lesson😃

 
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But also, isn’t 1.25m/s like really really fast?

Never thought about how many revolutions per second is in a "typical" loop. According to "Wei Xie, Kong Chuan Teh, Zhi Feng Qin": SPEED AND SPIN OF 40MM TABLE TENNIS BALL AND THE EFFECTS ON ELITE PLAYERS, that is somewhere between 100 and 150. So trying to increase it by 10 is "in the ball park".

Hi PBP, I like your service motion. You've been working on serve, didn't you?
 
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Never thought about how many revolutions per second is in a "typical" loop. According to "Wei Xie, Kong Chuan Teh, Zhi Feng Qin": SPEED AND SPIN OF 40MM TABLE TENNIS BALL AND THE EFFECTS ON ELITE PLAYERS, that is somewhere between 100 and 150. So trying to increase it by 10 is "in the ball park".

Hi PBP, I like your service motion. You've been working on serve, didn't you?
I edited the sentence out after 5 minutes because I realized that 1.25m/s is just normal walking speed.😂
Yes, for pro player I’m guessing it’s around that number.
And yes, I have been working on my serves, but they are still high and not so spinny. Still, thanks for the compliment.

 
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I edited the sentence out after 5 minutes because I realized that 1.25m/s is just normal walking speed.😂
Yes, for pro player I’m guessing it’s around that number.

Yes, I noticed you removed it. But I posted my reply anyway. I think there is nothing wrong about it. I also didn't know 10 minutes ago that 10 revs/sec is cca 10% of usual loop :)
 
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Wow, 100 to 150 I will have to "up" my game 😁
I just checked my setting in my robot and it was only 65 ( or 3850 rpm.m)
100-150 is the above average for pros…
Some matches on TV have a “winner RPM” which shows you how much spin the winning shot had. I see that it’s usually between 4500-5800 rpm, and it could be higher. So setting your robot to making yourself return Timo’s topspins is not exactly a good confidence builder😆

 
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Wow, 100 to 150 I will have to "up" my game 😁
I just checked my setting in my robot and it was only 65 ( or 3850 rpm.m)

Interesting, I should find out how much spin Amicus actually produces. If only I did care a little bit more :) I take this more like a curiosity. I think the "things" that make me move faster/better, are about 100'000% more important than how fast in m/s I actually move.
 
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Interesting, I should find out how much spin Amicus actually produces. If only I did care a little bit more :) I take this more like a curiosity. I think the "things" that make me move faster/better, are about 100'000% more important than how fast in m/s I actually move.
Try upping the spin and speed both to max. 😄

 
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Try upping the spin and speed both to max. 😄

We will do that when you come and visit 😂

For this specific shot the speed is set at 35km/h this is comfortable for me.
I set it like that after watching the Timo Boll video "fastest and slowest set up." when with the slowest set up he got about 40 odd km/h

Setting the machine at full speed is not recommended as it leaves permanent dents on the table surface

 
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Come on GUYS! The average high school soft ball pitcher can throw a soft ball under handed at 55 mph or just short of 25 m/s. Now assume a TT player can swing a paddle that fast. That better be safe assumption unless you are a wimp. Now not all of that speed can be used to just brush the ball to cause spin because there wouldn't be enough speed to get the ball over the net. if the paddle is brushed at the 1:30 point on the ball then about 70% if that speed can be used for tangential motion. The circumference of the ball is 2*PI*0.02m=0.126 m.
So (25 m/s) / (0.126 m/rev) = 199 rev/s but since only 70% of the paddle speed is applied tangentially then the result is about 140 rev/sec. The cosine of 45 degrees is 0.707. 150 rev/sec is about the max rev per second I have seen posted. I have a Butterfly video where a chopper is returning the ball with over 130 rev/sec back spin.

My point is that 1.26 m/s extra speed on the stroke is a only about 5% of max paddle speed. That is asking for very little yet it makes such a big difference. Now the trick is knowing when to trade of spin for speed by how much you brush the ball at contact. Also, even little girls should be able to return a 130 rev/sec back spin ball with the right technique. The tangential upwards stroke must match the rotational back spin speed so the ball does not push off the paddle and go down into the net or table.

Now what makes me shake my head is all the talk about boosters and faster rubbers when the real problem is controlling what you have.

BTW, my Newgy 2050 robot can, in theory, shoot a ball at 30 m/s. That was probably when it was new. Since there is a friction pad on the bottom, that part of the ball is not moving at all so the top part of the ball is in contact with the throw wheel and it is moving the top part of the ball at 60 m/s so the average is 30 m/s. Using the same calculation as above, the center of the spin on the ball should be ( 30 m/s ) / ( 0.126 m/rev ) = 238 rev /sec. I don't believe the true rev/sec is that high but it is high since I have made some assumptions that every thing is perfect which it isn't. I bet the throw wheel motor slows down a bit when it is under load and there is some slip between the throw wheel and the ball. Have any of you tried moving your robot back away from the table and shooting the ball at full speed and back spin and tried to loop it back? I have.
 
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I edited the sentence out after 5 minutes because I realized that 1.25m/s is just normal walking speed.😂
Yes, for pro player I’m guessing it’s around that number.
And yes, I have been working on my serves, but they are still high and not so spinny. Still, thanks for the compliment.

In theory, the gap is just so small and we can all become pros tomorrow if we can swing the bat faster, isn't it?

But we tend to forget, the ball will come back faster and your "high rotation" will also come back higher too.
Until, you are in that level, I actually don't feel it is necessary to even talk about high rotation of the ball.

Normally, coaches ask for consistency. If you can't hit 20 or 30 shots on, what is the use of 1 high "PRO" level shot, but you get 1 out of 3 on?
or the ball comes back, and your chance of getting the ball on drops another 10~90%?

Table tennis cannot be compared to a pitcher or a golfer, who can just swing the club/arm and generate everything from a stand still.
I mean, if you can't even move body correctly, or step correctly to generate the right body weight to life the ball up, talking about swinging the bat properly, is like trying to run before you can even craw.

When I coached non system trained players, I find it that they all want to swing harder and faster - this is very normal.
I need to undo they minds and tell them this:
1) if you can't get your feet there, you can't get your body there
2) if you can't get your body there, you can't get your arm there
3) if you can't get the above there, you are in no position to execute that stroke correctly
4) if you can't execute that stroke properly, you have little to no control over that stroke
5) and then you ask, why the ball some times goes in, and some times it doesn't.

One of our top high level players coming in (for grade 10), has a very good forehand.
She moves well, but she is too parallel to the ball (her legs) and she rallies too much on her arm. So in high power rallies, she is always on the loosing side when she needs to make more than 3 hits.

In training mode, she can get there in time (despite the wrong foot position), but in open play and her fundamental flaws shows.
This is how pro players weaknesses get exposed and how opposition teams work out game plans.

We saw this issue, and will need to change her over time. And obviously the player at first won't understand the problem - since she is on the higher part of the average in terms of results, and has done well in the 8 years prior (she used that power to over power her opponents), but the older you get, the bigger your fundamental flaws you have, the easier it will be exposed to when the rallies become faster and spinner.
So if I am the opposition coach, I would say, don't even attack her, let her attack you and just block 5 to 10 balls on and she will eventually be late on her shot and hit the ball off.

Other than her flaws in movement, her arm only action will also lead to injuries.
So the head coach on the 1st week actually told her - don't hit so hard, reduce your power,

So yeah, I think this apply to all.
You can't just hit harder or swing the bat faster. In theory, you also need to beware of injuries too!

 
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In theory, the gap is just so small and we can all become pros tomorrow if we can swing the bat faster, isn't it?

But we tend to forget, the ball will come back faster and your "high rotation" will also come back higher too.
Until, you are in that level, I actually don't feel it is necessary to even talk about high rotation of the ball.

Normally, coaches ask for consistency. If you can't hit 20 or 30 shots on, what is the use of 1 high "PRO" level shot, but you get 1 out of 3 on?
or the ball comes back, and your chance of getting the ball on drops another 10~90%?

Table tennis cannot be compared to a pitcher or a golfer, who can just swing the club/arm and generate everything from a stand still.
I mean, if you can't even move body correctly, or step correctly to generate the right body weight to life the ball up, talking about swinging the bat properly, is like trying to run before you can even craw.

When I coached non system trained players, I find it that they all want to swing harder and faster - this is very normal.
I need to undo they minds and tell them this:
1) if you can't get your feet there, you can't get your body there
2) if you can't get your body there, you can't get your arm there
3) if you can't get the above there, you are in no position to execute that stroke correctly
4) if you can't execute that stroke properly, you have little to no control over that stroke
5) and then you ask, why the ball some times goes in, and some times it doesn't.

One of our top high level players coming in (for grade 10), has a very good forehand.
She moves well, but she is too parallel to the ball (her legs) and she rallies too much on her arm. So in high power rallies, she is always on the loosing side when she needs to make more than 3 hits.

In training mode, she can get there in time (despite the wrong foot position), but in open play and her fundamental flaws shows.
This is how pro players weaknesses get exposed and how opposition teams work out game plans.

We saw this issue, and will need to change her over time. And obviously the player at first won't understand the problem - since she is on the higher part of the average in terms of results, and has done well in the 8 years prior (she used that power to over power her opponents), but the older you get, the bigger your fundamental flaws you have, the easier it will be exposed to when the rallies become faster and spinner.
So if I am the opposition coach, I would say, don't even attack her, let her attack you and just block 5 to 10 balls on and she will eventually be late on her shot and hit the ball off.

Other than her flaws in movement, her arm only action will also lead to injuries.
So the head coach on the 1st week actually told her - don't hit so hard, reduce your power,

So yeah, I think this apply to all.
You can't just hit harder or swing the bat faster. In theory, you also need to beware of injuries too!

TLDR: All power and no consistency gets you Koki Niwa’d 🤣
(I get the point)

 
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Okay, haven't really had the time to give you a proper comment.

Using multiball, is the quickest to get back.
multiball can help your movement, and when your movement is better, so will your confident level be.

In your video, you are almost late for every stroke. Your body - arm - contact point, say we can make this the ping pong triangle, needs to be a triangle at all times.
So you need to be in position before you shot. Not trying to bend around like Neo from the Matrix (when dodging bullets).

Go with 2 point FH drills, 2 point FH, 2 point BH, 1 BH + 2 FH etc, these are all simple drills, and when your movement improves, slowly and surely you can hit more balls and look a lot cooler!
 
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Okay, haven't really had the time to give you a proper comment.

Using multiball, is the quickest to get back.
multiball can help your movement, and when your movement is better, so will your confident level be.

In your video, you are almost late for every stroke. Your body - arm - contact point, say we can make this the ping pong triangle, needs to be a triangle at all times.
So you need to be in position before you shot. Not trying to bend around like Neo from the Matrix (when dodging bullets).

Go with 2 point FH drills, 2 point FH, 2 point BH, 1 BH + 2 FH etc, these are all simple drills, and when your movement improves, slowly and surely you can hit more balls and look a lot cooler!
I should get one more session with my coach tomorrow, I’ll make some adjustments. After that we have a week of law mandated military training.

 
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I did 30 yrs of military training, I would say that is easily just a little excessive, so I would say 1-2 years would be a healthy amount for anyone in any society. Military training and military life can be full of bullshyt, but it can also lead to individuals working as a team and having discipline... that translates well into real life.
 
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I did 30 yrs of military training, I would say that is easily just a little excessive, so I would say 1-2 years would be a healthy amount for anyone in any society. Military training and military life can be full of bullshyt, but it can also lead to individuals working as a team and having discipline... that translates well into real life.
You’re right on that.

 
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