Vibration analysis between '20 Met and '21 Zillion
Posted: Tue Feb 16, 2021 8:03 pm
*******___________Important Message:_______**********
******* This is not a competition with a winner **********
*******____This is pure boredom, manifested__**********
This awful weather has got us Southerners prisoners in our own homes and being a caged animal is about to drive me crazy. So much so that I spent the past few days setting up an experiment to measure overall vibrations felt during reeling. You read that correctly. I was so bored that I figured out a way to slap accelerometers to bait casters so I could measure vibrations in various reels.
If the weather stays bad a few more days I will do some more reels. For now, all I've tested is a 2020 Metanium and a 2021 Zillion.
The Setup
To begin, I basically created some "soft constraints" by placing the reel in a lightly tightened vise with foam borders. This was to constrain the reel such that low frequency vibrations, like a human hand, would not be possible. But higher frequency vibrations from gearing, etc. would still show up on the accelerometer.
The accelerometer is just a basic witmotion 6-axis with bluetooth so I can just log the data on my iPhone while it runs. I used some 3M sticky stuff to attach it to the reels. I tried placing the accelerometer both to the top and palm side of the reels. The results didn't change (which is a good thing) so I ultimately just left it on top of the frames because it was easier to deal with.
Both reels are 7.1:1 gear ratios. Even though I was ultimately interested in the magnitude of the vibrations, I didn't want varying frequencies to throw off the look of the charts. So you will see the very consistent spikes in similar frequencies for both of these reels.
Even though the reels were in a vise, I did the reeling by hand. You will see from the data that I was pretty good at achieving a consistent ~2.5 Revolutions Per Second over 20-30 seconds of data logging. I tried some data at ~1 RPS, but the outcome didn't change and it was tougher to maintain 1 RPS than ~2.5 RPS.
The Output
I logged all the spatial dimensions (X, Y, Z) accelerations for about 25-30 seconds of reeling. In the coordinate system I chose, X would be side-to-side movement, Y is front-to-back movement, and Z is up-and-down movement. The plots below only show X and Z movement as the Y-direction movement was always minimal (order of magnitude less) when compared to the others.
The charts you will see are not actually raw accelerations over time. What you will see is the Discrete Fourier Transform algorithm applied to the raw acceleration data (https://en.wikipedia.org/wiki/Discrete_ ... _transform). The DFT representation helps make a clear statement about the messy raw acceleration data that would be almost impossible to digest otherwise.
There are two important aspects of a DFT plot. First is the various spikes at different frequencies. These spikes represent the main set of frequencies that are apparent in the overall accelerometer signal. Next is the amplitude of those main frequency spikes. Higher amplitudes represent a larger overall acceleration magnitude at the particular frequency of interest. So for example, if the chart has a spike at 2.5Hz with an amplitude of 0.2m/s^2, that is a consistent, repetitive, signal one could expect to feel while reeling.
For those that are already knowledgeable about this stuff, I FFT'd various 10 second windows of the data until I found the lowest RMS, most consistent, data to express.
The Data
Okay, so first up is the 2020 Metanium. Here is the plot.
And here is the 2021 Zillion.
The Analysis
First off, it's pretty cool to see the 5, almost identical, frequencies pop up for both reels. This was to be expected with the same gear ratios, but still cool nonetheless.
I'm not gonna get too wrapped up in a frequency analysis, but the spikes at 2.5, 5, 7.5, 10, and 12.5Hz are signs of consistent reeling on my end plus the effects of gearing throughout the reel. Also, two reels with the same gear ratios are showing very similar reactions to reeling on a frequency spectrum.
The coolest part to me is the amplitude differences. If anybody has been keeping up with the Zillion mega-thread, I said in there the new Zillion was easily the smoothest reel I've ver felt. Well, I think I found some data to back that up. The reel transmits anywhere from 3-4 times less vibration to the frame than the Metanium does. It's just a smooth operator.
Now this also brings up an interesting topic of discussion regarding Magnesium frames. I've heard a lot of folks talk about sensitivity of Magnesium and being able to feel bites through the reel frame. I never really put a lot of faith in those arguments; however, after seeing this, I think it's plausible that a Magnesium frame could be responsible for transmitting vibrations due to bites into your hand.
Anyways, hope y'all found this interesting. I'd much rather just go fishing than do this, but here we are.
******* This is not a competition with a winner **********
*******____This is pure boredom, manifested__**********
This awful weather has got us Southerners prisoners in our own homes and being a caged animal is about to drive me crazy. So much so that I spent the past few days setting up an experiment to measure overall vibrations felt during reeling. You read that correctly. I was so bored that I figured out a way to slap accelerometers to bait casters so I could measure vibrations in various reels.
If the weather stays bad a few more days I will do some more reels. For now, all I've tested is a 2020 Metanium and a 2021 Zillion.
The Setup
To begin, I basically created some "soft constraints" by placing the reel in a lightly tightened vise with foam borders. This was to constrain the reel such that low frequency vibrations, like a human hand, would not be possible. But higher frequency vibrations from gearing, etc. would still show up on the accelerometer.
The accelerometer is just a basic witmotion 6-axis with bluetooth so I can just log the data on my iPhone while it runs. I used some 3M sticky stuff to attach it to the reels. I tried placing the accelerometer both to the top and palm side of the reels. The results didn't change (which is a good thing) so I ultimately just left it on top of the frames because it was easier to deal with.
Both reels are 7.1:1 gear ratios. Even though I was ultimately interested in the magnitude of the vibrations, I didn't want varying frequencies to throw off the look of the charts. So you will see the very consistent spikes in similar frequencies for both of these reels.
Even though the reels were in a vise, I did the reeling by hand. You will see from the data that I was pretty good at achieving a consistent ~2.5 Revolutions Per Second over 20-30 seconds of data logging. I tried some data at ~1 RPS, but the outcome didn't change and it was tougher to maintain 1 RPS than ~2.5 RPS.
The Output
I logged all the spatial dimensions (X, Y, Z) accelerations for about 25-30 seconds of reeling. In the coordinate system I chose, X would be side-to-side movement, Y is front-to-back movement, and Z is up-and-down movement. The plots below only show X and Z movement as the Y-direction movement was always minimal (order of magnitude less) when compared to the others.
The charts you will see are not actually raw accelerations over time. What you will see is the Discrete Fourier Transform algorithm applied to the raw acceleration data (https://en.wikipedia.org/wiki/Discrete_ ... _transform). The DFT representation helps make a clear statement about the messy raw acceleration data that would be almost impossible to digest otherwise.
There are two important aspects of a DFT plot. First is the various spikes at different frequencies. These spikes represent the main set of frequencies that are apparent in the overall accelerometer signal. Next is the amplitude of those main frequency spikes. Higher amplitudes represent a larger overall acceleration magnitude at the particular frequency of interest. So for example, if the chart has a spike at 2.5Hz with an amplitude of 0.2m/s^2, that is a consistent, repetitive, signal one could expect to feel while reeling.
For those that are already knowledgeable about this stuff, I FFT'd various 10 second windows of the data until I found the lowest RMS, most consistent, data to express.
The Data
Okay, so first up is the 2020 Metanium. Here is the plot.
And here is the 2021 Zillion.
The Analysis
First off, it's pretty cool to see the 5, almost identical, frequencies pop up for both reels. This was to be expected with the same gear ratios, but still cool nonetheless.
I'm not gonna get too wrapped up in a frequency analysis, but the spikes at 2.5, 5, 7.5, 10, and 12.5Hz are signs of consistent reeling on my end plus the effects of gearing throughout the reel. Also, two reels with the same gear ratios are showing very similar reactions to reeling on a frequency spectrum.
The coolest part to me is the amplitude differences. If anybody has been keeping up with the Zillion mega-thread, I said in there the new Zillion was easily the smoothest reel I've ver felt. Well, I think I found some data to back that up. The reel transmits anywhere from 3-4 times less vibration to the frame than the Metanium does. It's just a smooth operator.
Now this also brings up an interesting topic of discussion regarding Magnesium frames. I've heard a lot of folks talk about sensitivity of Magnesium and being able to feel bites through the reel frame. I never really put a lot of faith in those arguments; however, after seeing this, I think it's plausible that a Magnesium frame could be responsible for transmitting vibrations due to bites into your hand.
Anyways, hope y'all found this interesting. I'd much rather just go fishing than do this, but here we are.