Interpreting Eggtimer Data

BDB said:

I used an Eggtimer Quantum today for my first successful electronic staging today. The airstart worked beautifully using the main channel, but I think the ejection charge, which was set for nose-over on the drogue channel, fired prematurely. I'm trying to figure out what happened, but I'm not quite sure of the best way to plot and interpret the flight data. (An Excel sheet is attached.)

Am I correct in assuming that the Falt and Fveloc data are filtered altitude and filtered velocity data (presumably the derivative of Falt)? Should I plot this or the raw alt and veloc data? What is represented by the values in the columns on the right?

Side note: Does anyone have a suggestion for free or cheap software (preferably Mac) that lets me plot data and then zoom in on the graph? I know, I know....I'm a scientist, so you would think I would be fluent in MatLab. But I'm an organic chemist--I took a lot of math classes in college and never use them.

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Keisling said:

I use the Falt and Fveloc values since Alt and Veloc are raw baro readings and not filtered to remove noise from pressure differences not created by a change in altitude.

LDA = Launch Detect Altitude
LowV = The altitude in which the rocket slowed under 100 ft/sec
NO - The altitude at which the rocket nosed over

You can download a copy of the Quantum User's Guide here:https://www.eggtimerrocketry.com/attachments/File/Eggtimer_Quantum_1_06Q.pdf to get more detailed info on reading the table.

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rharshberger said:

If the Quantum was inside a transition or the static ports were not in clean airflow the data curves will be noisy.

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Buckeye said:

I just read the Eggtimer article in Sport Rocketry. The author showed some bizarre altitude plots from the Quantum.

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BDB said:

Here's a pic of the av bay and the static port. It had only one 1/8" port in a 1.6" x 5" clear BT60 payload bay. Maybe that's the issue?

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