A friend of mine sent me a spreadsheet (which I can share here if needed) that his Jolly Logic produced to output data. It gives all the data in 0.05 second increments, so there's a lot of it. Unfortunately the altitude has been rounded to the nearest foot, which I assume is because that's the most accurate that a barometric sensor can really do. There was also 3 dimensional acceleration but I didn't use it. To calculate velocity I converted the difference in altitude to miles, 0.05 seconds to hours, divided the two and got MPH.
Having the significant digits of the time at hundredths and the distance at 1.0 makes the velocity suspect.
So I did a second set of calcs that spread out over 10 readings, so that the calcs were over 0.5 seconds instead, which might help make the rounding of the altitude less of an issue.
As expected the velocity results are very different on the slower speeds but as the rocket gets faster the two speeds tend to be more similar.
Am I misunderstanding something about this process? Is there another, better, way to use this data to calculate velocity?
Having the significant digits of the time at hundredths and the distance at 1.0 makes the velocity suspect.
So I did a second set of calcs that spread out over 10 readings, so that the calcs were over 0.5 seconds instead, which might help make the rounding of the altitude less of an issue.
As expected the velocity results are very different on the slower speeds but as the rocket gets faster the two speeds tend to be more similar.
Am I misunderstanding something about this process? Is there another, better, way to use this data to calculate velocity?