Cue Hit Analysis

StrokeAnalyzer

AzB Silver Member
Silver Member
Hello all cue makers, scientists and anyone curious about cue hit characteristics.

During the development of the accelerometer for pool stroke analysis, I noticed reflections in the Z axis acceleration data due to reflections rattling up and down the cue after the cue ball was hit. I suspect these signals have something to do with cue construction or "cue hit". Things like joint material, ferrule material, tip type, wood type etc etc. I wrote a program specifically to analyze those signals. The program and hardware allows for acquiring the Z axis data from the cue hit, then takes the time domain data and does a Fast Fourier Transform of the time data to the frequency domain.

The following image shows a typical cue hit being analyzed. The top signal shows the raw data as captured. The middle signal is the data thats been trimmed for analysis. The bottom signal is the frequency components of the trimmed data. Markers have been applied to show the frequency peaks. Note the marks at location 5, 15, 171, 252, 334 and 409 hz. Those peaks are signal frequencies that are reflected up and down the cue after the cue ball is hit.

CueHitAnalyzer1.jpg

I am not saying I understand these signals or frequencies or how they relate to a cue's hit. The time domain data alone maybe useful by itself. I created the program for the curious cue maker or persons interested in quantifying a cue's hit. Maybe the information is useful, maybe not. Years ago I remember seeing a documentary about the tonal analysis of a Stradivarius violin and that got me thinking about this type of frequency analysis. Maybe this tool can help cuemaker's analyze and create cues that hit similar to the old classics or make thier own cue's hit with a designed repeatible hit. Imagine a cue maker is ask by a customer for a cue with a hit similar to a Super Dupper brand cue. That Super Duper brand cue should have a specific hit frequency spectrum. Building a cue with a specific hit MIGHT be easier to build if the cue maker knows how his and other cue designs hit.

This is something new for the pool world and cue makers, I'd like to see this new hardware and software utilized to hopefully improve cue making.

Initially I will give away the program for free with the purchase of the accelerometer hardware that is required to utilize the program. The cost of the hardware and software program that runs on a Windows pc is $100. I posted this here because I suspect there is little interest in the general forsale section. Maybe I'll post the info there also.

Let me know if you need more details, your interested or have questions.

Cheers
Bob
 

whammo57

Kim Walker
Silver Member
Hello all cue makers, scientists and anyone curious about cue hit characteristics.

During the development of the accelerometer for pool stroke analysis, I noticed reflections in the Z axis acceleration data due to reflections rattling up and down the cue after the cue ball was hit. I suspect these signals have something to do with cue construction or "cue hit". Things like joint material, ferrule material, tip type, wood type etc etc. I wrote a program specifically to analyze those signals. The program and hardware allows for acquiring the Z axis data from the cue hit, then takes the time domain data and does a Fast Fourier Transform of the time data to the frequency domain.

The following image shows a typical cue hit being analyzed. The top signal shows the raw data as captured. The middle signal is the data thats been trimmed for analysis. The bottom signal is the frequency components of the trimmed data. Markers have been applied to show the frequency peaks. Note the marks at location 5, 15, 171, 252, 334 and 409 hz. Those peaks are signal frequencies that are reflected up and down the cue after the cue ball is hit.

View attachment 282805

I am not saying I understand these signals or frequencies or how they relate to a cue's hit. The time domain data alone maybe useful by itself. I created the program for the curious cue maker or persons interested in quantifying a cue's hit. Maybe the information is useful, maybe not. Years ago I remember seeing a documentary about the tonal analysis of a Stradivarius violin and that got me thinking about this type of frequency analysis. Maybe this tool can help cuemaker's analyze and create cues that hit similar to the old classics or make thier own cue's hit with a designed repeatible hit. Imagine a cue maker is ask by a customer for a cue with a hit similar to a Super Dupper brand cue. That Super Duper brand cue should have a specific hit frequency spectrum. Building a cue with a specific hit MIGHT be easier to build if the cue maker knows how his and other cue designs hit.

This is something new for the pool world and cue makers, I'd like to see this new hardware and software utilized to hopefully improve cue making.

Initially I will give away the program for free with the purchase of the accelerometer hardware that is required to utilize the program. The cost of the hardware and software program that runs on a Windows pc is $100. I posted this here because I suspect there is little interest in the general forsale section. Maybe I'll post the info there also.

Let me know if you need more details, your interested or have questions.

Cheers
Bob


That is great stuff. Please get a selection of various cues and hit a cue ball and record the wave forms.

Joint screws.... brass SS G10
Butts...... maple, rose wood, etc cored non-cored
ferrules... no ferrule.... ferrule materials

etc....etc


This would be most interesting

Kim
 

StrokeAnalyzer

AzB Silver Member
Silver Member
I''ll post a little more general information...

You can see a picture of the Accelerometer package and how it attaches to the cue here...

http://www.strokeanalyzer.com/screenshots.htm

Accelerometer gadget connects to computer via a USB cable. Some additional details above the picture of the Accelerometer. I do not plan to test a bunch of cues. I wouldn't know what to do with the information anyway :p

Bob
 

Kid Dynomite

Dennis (Michael) Wilson
Silver Member
I''ll post a little more general information...

You can see a picture of the Accelerometer package and how it attaches to the cue here...

http://www.strokeanalyzer.com/screenshots.htm

Accelerometer gadget connects to computer via a USB cable. Some additional details above the picture of the Accelerometer. I do not plan to test a bunch of cues. I wouldn't know what to do with the information anyway :p

Bob
I love it!

I have given this topic great thought. This tool proves some of my theories on cue construction and performance. The longer the cue RESONATES THE BETTER! IMO

Wood selection or choices/combinations are essential along with construction.

Wood to wood jointed cues will have a long freguency interval then a piloted stainless steel jointed cue!

A satin sw or tad with UNIFORM WOODS in butts and shafts of MAPLE will resonate long and better then woods of mismatch type!

Say maple shaft and bocote forarm is worse than! Maple shaft and cored bocote with maple core!


These can all be tested and illustrate how cue fibration or lack of vibrations can be achieved. To me
The more vibration a cue sends to my hands the better! I believe i can make very tiny adjustments during those milliseconds of contact with the ball. I need that extended vibrations to adjust my stroke speed accordingly!

Kd
dSent from my XT907 using Tapatalk 2
 

Tony_in_MD

You want some of this?
Silver Member
Strokeanalyzer:

Have you contacted Dr. Dave with this new information and method?

A study like you purpose sounds right up his alley.
 

Kid Dynomite

Dennis (Michael) Wilson
Silver Member
Even better yet! set up a booth at expo and charge to test your cue. Might be surprised!

Kd

Sent from my XT907 using Tapatalk 2
 
Last edited:

Tony_in_MD

You want some of this?
Silver Member
Only if there was a full understanding of how to interpret the results from each cue.

The OP's own words "I am not saying I understand these signals or frequencies or how they relate to a cue's hit. The time domain data alone maybe useful by itself. I created the program for the curious cue maker or persons interested in quantifying a cue's hit. Maybe the information is useful, maybe not."

Which is why this device needs to be in the hands of people who are inclined to perform a study of different cues to see what factors in their composition and construction impact the results.


Even better yet! set up a booth at expo and charge to test your cue. Might be surprised!

Kd

Sent from my XT907 using Tapatalk 2
 

Kid Dynomite

Dennis (Michael) Wilson
Silver Member
Only if there was a full understanding of how to interpret the results from each cue.

The OP's own words "I am not saying I understand these signals or frequencies or how they relate to a cue's hit. The time domain data alone maybe useful by itself. I created the program for the curious cue maker or persons interested in quantifying a cue's hit. Maybe the information is useful, maybe not."

Which is why this device needs to be in the hands of people who are inclined to perform a study of different cues to see what factors in their composition and construction impact the results.
They could be compared with the other cues in your collection!

You could compare two cues you are considering buying!

So many ways to go with it and prize for best of show! Something small!

Start collecting data at event and see how wood to wood vs. Stainless? And etc.

Kd


Sent from my XT907 using Tapatalk 2
 

Tony_in_MD

You want some of this?
Silver Member
Yes all of that is possible but until you know what the output means, and how to interpret it is just a fun thing to look at.

They could be compared with the other cues in your collection!

You could compare two cues you are considering buying!

So many ways to go with it and prize for best of show! Something small!

Start collecting data at event and see how wood to wood vs. Stainless? And etc.

Kd


Sent from my XT907 using Tapatalk 2
 

RBC

Deceased
I love it!

I believe i can make very tiny adjustments during those milliseconds of contact with the ball. I need that extended vibrations to adjust my stroke speed accordingly!

Kd
dSent from my XT907 using Tapatalk 2

Sorry Dynomite, but I have to question this.

I find it hard to believe that you can actually achieve this, and here's why.

There are 2 types of vibrations that happen when you hit the cue ball.

The first is a linear sound wave that moves up and down the cue. The speed of sound through most hardwoods is around 13,000 feet per second, so at a .001 second contact time that sound would travel 13 feet. More than enough to reach your hand during the ball to tip contact. However, I don't think you can feel this type of vibration. Remember, it's a sound wave and there isn't any detectable "movement" of the wood, only sound. Without any feeling of this vibration, there isn't anything to react to.

The second is a lateral shake or movement of the cue. This comes from the "bend and rebound" of the cue as it strikes the ball. Obviously, because the cue has to bend under the force of the impact and then spring back to create this wave that moves down the cue to your back hand, it will take much longer than the time the tip is on the cue ball. So, by the time this wave makes it back to your hand the ball is long gone and your opportunity to make adjustments is past.

I don't mean to bust your chops. Your position is actually a very common one. We would all like to think we can make those adjustments, but I just don't think it's even possible.
 

Lexicologist71

Rabid Schuler fanatic
Silver Member
Sorry Dynomite, but I have to question this.

I find it hard to believe that you can actually achieve this, and here's why.

There are 2 types of vibrations that happen when you hit the cue ball.

The first is a linear sound wave that moves up and down the cue. The speed of sound through most hardwoods is around 13,000 feet per second, so at a .001 second contact time that sound would travel 13 feet. More than enough to reach your hand during the ball to tip contact. However, I don't think you can feel this type of vibration. Remember, it's a sound wave and there isn't any detectable "movement" of the wood, only sound. Without any feeling of this vibration, there isn't anything to react to.

The second is a lateral shake or movement of the cue. This comes from the "bend and rebound" of the cue as it strikes the ball. Obviously, because the cue has to bend under the force of the impact and then spring back to create this wave that moves down the cue to your back hand, it will take much longer than the time the tip is on the cue ball. So, by the time this wave makes it back to your hand the ball is long gone and your opportunity to make adjustments is past.

I don't mean to bust your chops. Your position is actually a very common one. We would all like to think we can make those adjustments, but I just don't think it's even possible.

Dead on the money here. That's not even taking into consideration reaction time. And THAT is assuming a correct reaction.
 

Tony_in_MD

You want some of this?
Silver Member
I was going to post my thoughts on this but you said it much better.

Besides even if the lateral shake was felt at the instance of tip contact (which it cannot be) , whose reaction time is even enough to feel, process and modify a moving arm in a .002 time span.



Sorry Dynomite, but I have to question this.

I find it hard to believe that you can actually achieve this, and here's why.

There are 2 types of vibrations that happen when you hit the cue ball.

The first is a linear sound wave that moves up and down the cue. The speed of sound through most hardwoods is around 13,000 feet per second, so at a .001 second contact time that sound would travel 13 feet. More than enough to reach your hand during the ball to tip contact. However, I don't think you can feel this type of vibration. Remember, it's a sound wave and there isn't any detectable "movement" of the wood, only sound. Without any feeling of this vibration, there isn't anything to react to.

The second is a lateral shake or movement of the cue. This comes from the "bend and rebound" of the cue as it strikes the ball. Obviously, because the cue has to bend under the force of the impact and then spring back to create this wave that moves down the cue to your back hand, it will take much longer than the time the tip is on the cue ball. So, by the time this wave makes it back to your hand the ball is long gone and your opportunity to make adjustments is past.

I don't mean to bust your chops. Your position is actually a very common one. We would all like to think we can make those adjustments, but I just don't think it's even possible.
 

Kid Dynomite

Dennis (Michael) Wilson
Silver Member
Tuning fork #1 is the shaft and Tuning fork #2 is the butt! If both resonance is G then butt vibrates! If mismatched? Via different species of wood? Then no vibrational transfer! Does stainless Steel joints help vibration or hurt vibration? I think hurt! Wood to wood, maple to maple from tip to butt best replicates OPTIMAL resonance transfer! Imo

Tap the stick and feel it shake in your hand. You can feel it shake in some good cues!

Kd

Sent from my XT907 using Tapatalk 2
 

Tony_in_MD

You want some of this?
Silver Member
If a steel joint hurts vibration why is a tuning fork made out of steel, and not wood?

As long as a joint is constructed correctly it does not matter if it is wood, steel, brass, piloted, flatfaced or ivory, it will transmit vibrations from the shaft to the hand.

This is the opinion of a hall of fame cuemaker I know.






Tuning fork #1 is the shaft and Tuning fork #2 is the butt! If both resonance is G then butt vibrates! If mismatched? Via different species of wood? Then no vibrational transfer! Does stainless Steel joints help vibration or hurt vibration? I think hurt! Wood to wood, maple to maple from tip to butt best replicates OPTIMAL resonance transfer! Imo

Tap the stick and feel it shake in your hand. You can feel it shake in some good cues!

Kd

Sent from my XT907 using Tapatalk 2
 

Tony_in_MD

You want some of this?
Silver Member
OK, but I think the difference of transfer is so small as to be nearly unnoticeable.

I am thinking back to the experiment conducted at one of the Texas Express 9 ball tourneys years ago where a bunch of cues whose joints and other ID features were masked and the participates could not ID the cues or the joint types by feel alone.

This stuff about the resonance of the shaft and the butt needing to be the same? The key of G???? Really????





Actually this is one that he basically got correct.

A change in material always changes the vibration transfer. Some of the longitudinal waves pass from material to material, some are reflected. Denser materials reflect more of the energy back into the original piece. A large mass in the center of a system will actually reflect a lot more of the longitudinal waves. This is the basis for why parents can 'see' their child in the womb and why you can make out the softer tissues (like eyes) in the fetus.

dld
 

RBC

Deceased
Dynomite

Those are cool videos! Resonance is really fun science.

However, they bare no relevance to your original statement that you could feel the vibration and make adjustments to your stroke while the tip was still touching the cue ball.

And, did you notice that the boxes were not touching each other?

Did you also notice that the transfer only happened when the open ends of the boxes were not only close to each other, but also aligned?
 

Kid Dynomite

Dennis (Michael) Wilson
Silver Member
The steel joint is like placing a sheet of metal duck work in between the two tuning forks! It blocks the vibration!

The tuning fork boxes are all uniform and made of same wood! The example shown would not work with mix match species woods! One rosewood and one oak uniform sized would not work!

Cues use touch to transfer vibration not air like the example. You can screw cue half way and shot balls and get the same feel as screwed down tight? No, you can't! That is why EVERYONE screws it down all the way for OPTIMAL vibration transfer!

Lining up the facing square and tight is essential as demonstrated by the boxes MUST be aligned!

Kd


The boxes do not touch but

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RBC

Deceased
.Ayn Rand wrote

"Reason is not automatic. Those who deny it cannot be conquered by it".

I will now leave you alone.

Shoot Well!
 
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