Eggtimer Quantum CSV Graphs

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VonRecktofen

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Hi Folks,
I've successfully built and flown my 2 Quantums now and I'm in need of a simple way to read/graph the flight data into Excell, kind of like the way a Jolly Logic Altimeter 3 graphs out flights....Is this possible?
I tried creating a scatter graph, and some of the velocity data was at high value extremes that made the graph look very small and compressed.
Can anyone point me in the direction of a tutorial or does anyone have a template for an Excell scatter graph that I could use?
Thanks for any help or ideas!

Franz in NJ
 

jpatton

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I've never played with those files so I don't have an easy answer for you, but if you want to shoot me one of the data files I'd be happy to see what I can come up with.
 

Arpak

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I use scatter plot with lines and then edit the axis values to just ignore the massive spikes, the auto values try to include everything.
 

Voyager1

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Those extreme values are probably noise or unwanted transients. I would just remove them or replace them with averaged values from adjacent good data.
 

cerving

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If you remove the outliers you'll probably get a much more useable graph. Unfortunately, baro velocity can be very wonky, for a number of reasons.
 

Kelly

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IIRC the output on those includes a raw altitude and velocity, and filtered values. Because velocity is just the time derivative of altitude, a minor error in altitude results in a huge error in velocity. So, you need to use the filtered values or the noise will be overwhelming.
 

VonRecktofen

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If you remove the outliers you'll probably get a much more useable graph. Unfortunately, baro velocity can be very wonky, for a number of reasons.
I've got to learn how to move columns next to each other so that I can create a scatter plot easier....
What data columns would I want to use to get a graph that looks kind of like the Altimeter 3 plot?
Thanks again, the Quantum flew flawlessly, even after being 75' up in a tree for a week in rough/cold/damp weather!

Franz in NJ
 

Arpak

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You'd want time for x axis and filtered velocity+filtered altitude for the y axis. You can click on the column letters at the top and it will select the whole column, do that and press ctrl to select multiple so you don't need to move then anywhere.
 

BDB

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Hi Folks,
I've successfully built and flown my 2 Quantums now and I'm in need of a simple way to read/graph the flight data into Excell, kind of like the way a Jolly Logic Altimeter 3 graphs out flights....Is this possible?
I tried creating a scatter graph, and some of the velocity data was at high value extremes that made the graph look very small and compressed.
Can anyone point me in the direction of a tutorial or does anyone have a template for an Excell scatter graph that I could use?
Thanks for any help or ideas!

Franz in NJ
I agree that the best part of the Jolly Logic Altimeter 3 may be the app. I love how easy it is to use and how good the data looks. If I had any ability to code, I'd love to write something like that for the data from my Quantums. But until someone does that, we're stuck with Excel.
 

cerving

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If you get rid of the two or three outliers and manually recalculate the velocity from FAlt ( Alt-Alt0/t-t0), this is what you get. You'll notice the spike right before apogee... my guess is that you're using motor eject as backup, and it popped before apogee. This is pretty typical...

1615313924745.png
 

jpatton

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Here is one in comparison to the sample I pulled from The AltimeterThree. I did put vel on the second one and dropped the -2400 velocity point, if you would want velocity to be more readable I'd use dual Y axis which I am not sure excel can do easily.

John
 

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cerving

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You can add a secondary axis in Excel... it just takes some extra clicks. Google is your friend... :)

Unless you have some outliers that need to be filtered out, or you're flying really high, you'll usually find that a single axis works fine.

1615322025824.png
 

jpatton

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Nice to know that excel can do it. I typically use graphpad for of the graphs I use so never dug to far into excel. Thanks for showing that.
 

VonRecktofen

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If you get rid of the two or three outliers and manually recalculate the velocity from FAlt ( Alt-Alt0/t-t0), this is what you get. You'll notice the spike right before apogee... my guess is that you're using motor eject as backup, and it popped before apogee. This is pretty typical...

View attachment 454453
Yup!
It was a motor eject as a back up!
Thanks for the ideas! I have to "go back to school" on this Excel stuff!
Franz
 

VonRecktofen

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Here is one in comparison to the sample I pulled from The AltimeterThree. I did put vel on the second one and dropped the -2400 velocity point, if you would want velocity to be more readable I'd use dual Y axis which I am not sure excel can do easily.

John
Thanks,
I'll have to check in to the dual Y axis mode!

Franz
 
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