A robot applying maximum spin?

DaWizard

DaWizard

Well-known member
I would be curious what the maximum amount of spin would be that a robot could generate.
Obviously robots can generate unbelievable accelaration in a cue, enough to launch the ball out of the street. But we want to keep it on the table.

- Where, relative to the center, would it have to be hit? (so that the ball remains on the table)
- Does this differ for top, back or sidespin?
- How could we measure the amount of spin?
- Would some kind of special cue tip be needed?
- Which freaky trickshots could it execute?

I would assume that @dr_dave has thought about this?
 
With the constraints of using normal equipment on a pool table, I am not sure if a robot can execute spin any better than a pro player, mostly due to the physical facts of friction and stability of a fairly light round object being hit on the side. I think the limitation would be friction of the tip on the ball not to just miscue, and also to keep the ball on the table.
 
DaWizard said:
I would be curious what the maximum amount of spin would be that a robot could generate.
Obviously robots can generate unbelievable accelaration in a cue, enough to launch the ball out of the street. But we want to keep it on the table.

- Where, relative to the center, would it have to be hit? (so that the ball remains on the table)
- Does this differ for top, back or sidespin?
- How could we measure the amount of spin?
- Would some kind of special cue tip be needed?
- Which freaky trickshots could it execute?

I would assume that @dr_dave has thought about this?
Click to expand...
The limit for miscues is about 50% from the center to the edge of the ball. That's true for humans and robots, and for any kind of spin. The spin has been measured with high speed video.
 
Ira Lee and myself had this discussion. We calculated that at break speed one could generate about 3500 RPM.

The normal range of shots in 9 ball are below 1000 RPM. Maybe 1500 RPM for an extreme English shot with a practical application. This is precisely measured with the DigiBall.
 
DaWizard said:
I would be curious what the maximum amount of spin would be that a robot could generate.
Obviously robots can generate unbelievable accelaration in a cue, enough to launch the ball out of the street. But we want to keep it on the table.

- Where, relative to the center, would it have to be hit? (so that the ball remains on the table)
- Does this differ for top, back or sidespin?
- How could we measure the amount of spin?
- Would some kind of special cue tip be needed?
- Which freaky trickshots could it execute?

I would assume that @dr_dave has thought about this?
Click to expand...
7
 
Uselesscamper said:
CNC as in a computerized subtractive machine? Do you mean some sort of robot? What does shear rate mean?
Click to expand...
Said robot in the title. Shear rate would be the rate at which the tip slips off the cue ball. Half baked idea that with zero follow through, a miscue would not cause catastrophic deflection. If the machine could hit fast enough, you might get "industrial" levels of horizontal rotation without undue forward motion.
 
hang-the-9 said:
With the constraints of using normal equipment on a pool table, I am not sure if a robot can execute spin any better than a pro player, mostly due to the physical facts of friction and stability of a fairly light round object being hit on the side. I think the limitation would be friction of the tip on the ball not to just miscue, and also to keep the ball on the table.
Click to expand...
I am curious about the results with regular equipement and anything made specifically for this. Wouldn't even know what to be honest. A cue tip with a special shape? Some gluey, spongey material?

Pros probably indeed have mastered it to a high degree within physical limitations. Still curious what machines would achieve... Burning felt probably
 
Bob Jewett said:
It's not acceleration that's important. That it matters directly is a common misconception. It's velocity that matters. And it's not unbelievable. Here is unbelieveable:

Click to expand...
I always thought it was acceleration that determines cue action. And that's why you follow through. So it's just the mass/velocity? DrDave has probably researched this in detail.
 
DaWizard said:
I always thought it was acceleration that determines cue action. And that's why you follow through. So it's just the mass/velocity? DrDave has probably researched this in detail.
Click to expand...
With no disrespect to DrDave, this has been known long before DrDave got on the internet. That said, DrDave does have some great velocity curves on his site as he *has* studied it in detail. The acceleration at impact is always near zero along the stroke line, which it should be. The velocity is normally at its peak, as it should be. The velocity should be near constant for a good amount of distance (a couple inches), which I think most people can figure why this leads to consistency in speed control.

Why do people think they’re accelerating through the ball? Because it feels like they are in a good stroke. The smooth acceleration should start from the back of the stroke, and it should follow a velocity profile shown in DrDave’s graphs. It shouldn’t start to decelerate prior to impact (though a good stroke can still be slightly decelerating since it’s the velocity that matters). A good follow through and thinking “accelerate”is a good thought process to prevent you from decelerating and breaking your stroke form.
 
DaWizard said:
I always thought it was acceleration that determines cue action. And that's why you follow through. So it's just the mass/velocity?
Click to expand...
The acceleration myth comes from the mistaken idea that you can increase tip/ball contact time (and therefore CB "action") by "accelerating through" the CB. The cue's speed actually drops (almost stops) during the 1/1000 second it's in contact with the CB, due to the flexible skin of the hand giving way.

pj
chgo
 
dquarasr said:
That’s cool. I wonder it the cloth under the spinning ball was burned at that one tiny spot the ball was spinning on.
Click to expand...
Its the 'sliding' of the cb that causes b'marks. According to Simonis the contact point on the cloth can reach over 400degF. That's what causes the marks. Its the pigment in the dye getting burned by the heat. That's why jump shots/break shots leave them, the heat generated by the ball being driven into/across the surface. A spinning ball won't burn cloth just due to spin alone.
 
Bob Jewett said:
The limit for miscues is about 50% from the center to the edge of the ball. That's true for humans and robots, and for any kind of spin. The spin has been measured with high speed video.
Click to expand...
I wonder how the maximum speed drops, relative to this 50% edge. From experience id say that the firther from the edge, the fewer the velocity. And it drops fast the further you reach that 50% edge.

But then what generates most spin? A hit close to the center with "industrialisatie force"? Or a hit close to the edge, at the limit of miscueing?
 
Still I would love to see a robot do insane spin shots. And we havent even talked about masse shots!
 
DaWizard said:
Still I would love to see a robot do insane spin shots. And we havent even talked about masse shots!
Click to expand...
Plastic PVC end-cap on a Dremel... hold vertically and place cue ball inside.

Dump it out at 30,000 RPM.

That should be insane enough.

Prepare to replace cloth due to burn marks.
 
You must log in or register to reply here.
Back
Top