Are you serious? For me, there is very little difference between backspin and topspin.
Help me choose a robot.
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Suggest you to get hold of Samson and you can ask him how strong is the back spin and top spin.
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What do you mean? The trajectory is deceptive, but I assure you there is significant enough spin, at least enough to satisfy those ~2500usatt players. As shown in Dario's video the power pong/amicus can produce incredible top and backspin, and the Samson videos show you can alternate between the two.
You are right that there is a small delay to change wheel speed due to inertia, but this is negligible for powerful brushless motors, and the change limit is really defined by software. For the minimum timing to switch between max backspin and topspin IDK, email Power Pong is the best option, unless someone on TTD would want to test for you.
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I think I understood you well. I answered that this robot can do everything you asked, I did not say that this is exactly what was demonstrated in these videos. The videos are there so you can get an idea.
Let's say in this part of the video (one exercise -> https://youtu.be/X2GbhVn6xXE?t=537) there is a strong backspin, followed by a topspin. It is not in one second as you would like, but for this exercise this is the appropriate time gap between the thrown balls. If you want, I can test the minimum time interval in which it can spin a strong backspin and then topspin.
That would be good. Can I ask you to record a video of how the robot sends balls to the racket as in the video (https://youtu.be/x8-pdEkS9x4).
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I wish to have a robot ....................... high quality one 😔😭
I have two robots and both are so cheap, one is that Joola [or whatever] V300, it was good in the past but lost its performance so far and for basic balls, and it only performs good with old 40mm balls, then i think last year i bought another cheap robot with remote also but has two head, i never took it out of the box for test yet, and i don't know what i can expect from it, now because i buy only cheap robots, can i buy another cheap one so in this case i can have say 3 robots with 4 heads and then i can set them all for different balls throwing and it can do good job for me like an expensive robot? I mean it is like 3 robots in 1, and i don't know which third cheap robot it will be then.
Cheap i mean less than $200-250
I have two robots and both are so cheap, one is that Joola [or whatever] V300, it was good in the past but lost its performance so far and for basic balls, and it only performs good with old 40mm balls, then i think last year i bought another cheap robot with remote also but has two head, i never took it out of the box for test yet, and i don't know what i can expect from it, now because i buy only cheap robots, can i buy another cheap one so in this case i can have say 3 robots with 4 heads and then i can set them all for different balls throwing and it can do good job for me like an expensive robot? I mean it is like 3 robots in 1, and i don't know which third cheap robot it will be then.
Cheap i mean less than $200-250
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Just to add some context to what Romanoff is referring to: The robopong "4050xl" does not exist, it is a joke by RDV: it is a homemade modified robopong 1040 (basket and feeder) with added homemade three motor system controlled by an ESP32. Sort of like a homemade tennirobo (servo head, three brushless motors).
My guess is the motors in the PowerPong/Amicus Prime are physically possible to switch speeds that fast, but the software limits you for doing that. So, the answer is to ask PowerPong company to expand the functionality (they will probably say no), hack your PowerPong or the PowerPong app, or build your own like RDV or Sergei from TenniRobo.
Although it would be cool to have something like the robopong "4050xl", That is not really necessary for drilling purposes. Whatever PowerPong's artificial limits are for spin and serve frequency are good enough. Again, having something with no limits like the "4050xl" would be really cool though.
https://mytabletennis.net/forum/robopong-4050xl-best-tt-robot_topic89452.html
www.youtube.com/watch?v=p4C1WgZZ9nk
https://www.newgy.com/collections/robots/products/newgy-robo-pong-1040
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Deal. I will try to record a similar video today when I get home from work, and send it to you.
I continue to study robots.
I'm starting to understand why the Amicus and PowerPong motors don't change speed fast enough. They have low power supplies. Amicus has an average power of about 60 watts, PowerPong has a 24 volt 3 amp (72 watt) power supply. Tennirobo and rdv have brushless motors like those used on quadcopters. For example, the Racestar BR2212 1400kv motor. Size 27x28 mm, weight 52 grams, at a voltage of 11 volts, the no-load current is 0.6A, the maximum current is 19A, the maximum power is about 200W. In Amicus and PowerPong, the power delivered to one motor can be approximately estimated at 20W (3x20 out of 72). The rdv has a 190w power supply in the circuit. Approximately 60 watts can be allocated to one motor. There should be a relationship between the set speed and the power given to the motor. For example, speed up from 0 to 5000 rpm at 20W in 2 seconds, at 40W in 1.2 seconds, at 60W in 0.8 seconds. If we draw an analogy with a car, one has an engine power of 40 hp, speed up to 100 km / h in 40 seconds, the other has 300 hp, speed up to 100 km / h in 5 seconds. But both cars can travel at a speed of 100 km/h.
P.S. We are waiting for the robot Amicus Prime plus from Butterfly, with a 150W power supply, the price is $2500. And the Amicus Super Prime model with a 250W power supply for $3,000 😊.
I'm starting to understand why the Amicus and PowerPong motors don't change speed fast enough. They have low power supplies. Amicus has an average power of about 60 watts, PowerPong has a 24 volt 3 amp (72 watt) power supply. Tennirobo and rdv have brushless motors like those used on quadcopters. For example, the Racestar BR2212 1400kv motor. Size 27x28 mm, weight 52 grams, at a voltage of 11 volts, the no-load current is 0.6A, the maximum current is 19A, the maximum power is about 200W. In Amicus and PowerPong, the power delivered to one motor can be approximately estimated at 20W (3x20 out of 72). The rdv has a 190w power supply in the circuit. Approximately 60 watts can be allocated to one motor. There should be a relationship between the set speed and the power given to the motor. For example, speed up from 0 to 5000 rpm at 20W in 2 seconds, at 40W in 1.2 seconds, at 60W in 0.8 seconds. If we draw an analogy with a car, one has an engine power of 40 hp, speed up to 100 km / h in 40 seconds, the other has 300 hp, speed up to 100 km / h in 5 seconds. But both cars can travel at a speed of 100 km/h.
P.S. We are waiting for the robot Amicus Prime plus from Butterfly, with a 150W power supply, the price is $2500. And the Amicus Super Prime model with a 250W power supply for $3,000 😊.
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Thats actually cool, but what is the purpose?
I saw that one scene where the robot is placed away from the table. One under spin, one top spin
so while the under spin shot goes out, then the top spin.
So if i'm the player on the other side, the "1st" ball gets shoot out, and while i'm waiting for it, I must hit the "2nd" ball first?'
Are we making robots for robots? or is it actually or humans?
I occasionally go to the rdv channel. He improves the program. Now he has a customizable departure delay for each ball. When the robot is standing 2 or 3 meters from the table at the topspin, the flight speed is higher than that of the ball with the bottom rotation, they arrive at the table almost simultaneously. You can add a delay before the topspin is released, for example, 300ms. This mode is similar to playing against a defender who sometimes does counter topspins, such as 3 backspin and 1 topspin. It is advisable to put the robot a little lower than the table level.
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He is demonstrating the maximum potential of the DIY robot, but of course you would not try to drill with that. You would program it appropriately for whatever drill you wanted.
The purpose is building this robot is for fun and education, to hack on stuff and build your own stuff. Or, if you want a cheap DIY robot (at the expense of hours used on building and programming).
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Interesting, I have not thought of the possibility of not enough power limiting speed change. Unfortunately I don't know enough about this topic to comment further.
Great, so you decided to get the Amicus! I am confused though, what is the "Amicus Super Prime"? I am also surprised that PowerPong and Amicus have different power supplies, as they are the same robot otherwise. Where did you get the information on the power supplies?
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Yeah, I guess the fun part is the only part I can understand.
from a coaching part, feeding balls, whether robot or human, the most important trait is it must be realistic.
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as promised... I made a video showing what you asked for.
first, three pictures are shown where the exercise settings are, followed by the exercise, and at the end there is a slow motion
https://youtu.be/Ng7G0x2Mw3o
first, three pictures are shown where the exercise settings are, followed by the exercise, and at the end there is a slow motion
https://youtu.be/Ng7G0x2Mw3o
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speed -> 120 balls per minute
it's not even close to the real situation in the game, because as you can see the thrown ball hasn't reached my racket yet (I'm standing at the table) and the robot is already throwing another ball.
just like you said, one with a lot of topspin, the next with a lot of backspin and so on.
it's not even close to the real situation in the game, because as you can see the thrown ball hasn't reached my racket yet (I'm standing at the table) and the robot is already throwing another ball.
just like you said, one with a lot of topspin, the next with a lot of backspin and so on.
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I am the founder of PongFox table tennis robot . Our robot has three wheels and for topspin loop the motor 2 (at the bottom) actually goes backwards. The wheels are programmable so you can play around with the settings and we have a random option which lets you choose multiple strokes .
Take a look and connect with me if you have more questions
Take a look and connect with me if you have more questions
Thank you very much for this video. I watched it several times. It, as we say, “dots all the i”. My analysis: standing on the side of the table, you turn on the robot. You can hear the motors running. You get up in the playing area, during this time the motors picked up speed. The first topspin has a strong rotation and, bouncing off the racket, flies out of the frame. All subsequent topspins have a weaker rotation and fall into the robot's grid (the motors do not have time to pick up speed). If you reduce the speed of the balls, for example to 30 balls per minute, then all the topspins will be more like the first topspin (the motors may have time to pick up speed, but this needs to be checked). It turns out that the force of rotation depends on the frequency of ball departures, balls that differ greatly in rotation cannot be combined into a series. For example, 1 ball is a short serve with strong bottom spin (top motors spin backwards, bottom motors spin forward). We set up the robot for this feed, everything is fine. Set up 2 ball (separate from 1). 2 ball is a slow topspin, but with strong spin. This is a typical game situation, I accept the cutoff serve, it flies a little over the edge of the table, the partner makes a topspin. For 2 balls, the top motors rotate forward, the bottom motor rotates backwards. Set up 2 ball, everything is fine. Then we combine these balls into a series, and everything is bad here. 2 the ball will be completely different, and not the one that was set up (the motors need to have time to change the rotation to the opposite). With a change in the speed of the balls from 30 to 120 per minute, there will be a different force of rotation and the speed of the ball.
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