Looks awesome and like you are getting close to your minimum viable product (if not already there from a design standpoint).
DigiBall accuracy
- Thread starter nataddrho
- Start date
You may want to look into the same function with just a camera and a normal cue ball. It's possible to calculate the tip contact point, speed and spin from successive frames of video. You would need a marked cue ball such as the measles ball.
You would need a pretty high FPS camera (or a camera array) to do that I would think? That's how optical golf ball flight monitors work by tracking the rotation of the ball's logo or dimples.
This can be part of the test plan. I know someone in Colorado with a high speed camera
For MVP, design, firmware, and app done. This year I am working on manufacturability optimization and FCC certifications.
Awesome, this will be cool to pair with instructional videos for position play. Can't wait! Would love to help test it out if you need feedback.
I have some Flutter experience and lots of Android experience (macOs/Linux also) ... if you need any help/get stuck on something. Not so much of a iOS and Windows person, but I can cope if needed.
Exactly right.
I like the DigiBall more than the DigiCue because it tells you what actually happened to the cue ball, regardless of your stroke quality. It really highlights your vision alignment and awareness of where the tip went. And not just the center of the tip, I mean the exact contact point from the tip to the ball, much smaller than a chalk mark.
It is very surprising and enlightening when you use it.
I think some iPhones already do 240 FPS. At 10 MPH the cue ball will move about a third of its diameter between frames at that rate. One huge advantage of developing an optical method of getting the results is that it is primarily software and can work with any good enough camera. Cameras are going to get better. Another huge advantage is that you can use any cue ball that has sufficient markings to keep track of the rotations.
Cameras are great since they are external observers but the downside is that they require setup as a static system. They are really only good for experiments in a controlled environment, not for the average consumer.
An internal sensor doesn’t require any equipment, anywhere. You never need to touch or move the ball to align it or set it in place, and you can literally play full sets of pool games with opponents while getting extremely accurate English feedback. You can even place the app into Talk mode and the phone will speak to you, so you don’t even need to look at anything.
You can walk into a pool hall and start playing immediately, no set up required, no tripods, obstructions, or any thing on your pool cue.
No more looking at chalk marks on training balls.
If I can use slow motion mode on my iPhone to make some verification videos then that’s a good idea
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I never got mine to work. It’s just been hiding in a drawer somewhere ever since I bought it.
Bob, I was curious and confirmed you are correct. My 5 year old Android phone was able to pick up several frames of ball rotation after impact using its slow mo mode. With some simple code it is easy to identify the ball and its logo (the blurry center smudge in the below). From rotation of that logo you could calculate ball spin and from the known FPS and change in the ball center point you can estimate speed. But there's no easy way to identify tip impact location.
That's given directly by rotation and speed. I'm pretty sure that's how the digiball works but I could be wrong.
Correct, gravity vector, rotational velocity vector, impact vector, scalar translational speed, linear algebra, filtering and processing.
I’m a new to the game of pool, serious about improving my game.
I bought a cue stroking glove but I just couldn’t figure the fingers out. It mostly remains in my cue case unused.
The slip rubber butt sensor provides feedback by vibrating as I’m stroking? All these talking stainless steel robots and pictures and graphs and algorithms just confuse the **** out of me. First of all, is it slip on or slip in? You’re telling me that there’s no other slip on rubber butt sensor on the market like it?
Technique. Does it measure desire? Enthusiasm?
Are we dealing with pure science here?
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Desperate for attention tonight? Good luck.
Even given the previous reference that the electric cue ball industry is currently experiencing excess demand, I feel that data comes on the back of weaker-than-expected Q4 sales. Any economic rebound driven by reopening may take longer than expected. Against that backdrop, here’s to surging electric cue ball sales that are ahead of analyst expectations. Robust.
My Digicue worked fine, and did what it said it would do.
Looking forward to getting a Digiball.
What does the DigiBall look like, and how does it work?
Sent from my iPhone using Tapatalk
The ball is identical in every way to a normal Aramith cue ball... cast phonelic resin, homogenous moment of inertia, balanced center of mass, shock resistant, perfectly round and polished surface, 1oz/in3 density, 6oz, 2.25" diameter, etc... except there is a sensor embedded in the center of the ball. It is wirelessly rechargable, and it transmits data to a mobile device about what English was applied to the ball, the spin, speed, tip location at impact, etc.
In other words, it is a training ball like the iCue or Rempe ball, but one that has no markings, is digital, and one that you never need to align or even touch, and is much much more accurate than looking at a chalk mark after the hit.
So what, what is the point? Why would anyone want an electric cue ball?
The biggest benefit I found is that the immediate, hands-free feedback not only lets you play real games (even with opponents), but allows you to compare your imagined tip target to what really occured... it makes very obvious any eye alignment errors or perception errors you might have, and it does so very quickly, within a few dozen shots. The accuracy of a gravity-aligned spin-calculated system is far more precise than hand alignment of a marked training ball due to unavoidable alignment errors done by eye. Another benefit is that you can set up the same repeated shot of you choose and develop a scatter plot of your shots, just like a target with a rifle.
It is also a passive system, meaning that it reads inertial moments only... there are no actuators or motors that will cause the ball to change paths. Jokes about a smart cue ball magically going into a pocket are funny, but this product can only observe, not manipulate