I’ve been working on the routine that converts my logged GPS and altimeter data into Google Earth .KML files.
It’s a lot nicer looking now – below is the same flight I posted on July 19 2008, but re-converted with the new routine.
Black marks pre-flight data, green marks ascent, yellow marks apogee (actually 1.5 seconds of data starting with apogee) and red marks descent. The lighter “whitish” marks are the GPS fixes, in this case 1.0 seconds apart. All the data in between is from the altimeter (25 Hz samples), with interpolated lat/lon position.
Here’s the .KML file – it’s fun to load it into Google Earth and fly around the track.
You can see where the rocket electronics detected launch (where black turns to green) and where it detected apogee and ejected the parachute (where green turns to yellow) – the crazy below-the-ground data point is the overpressure (sensed by the altimeter) from the ejection charge.
Last, if you click on the pad icon, you’ll see all kinds of flight data, automatically calculated from the log by the new routine.
It’s rather ugly MATLAB/SCILAB code. Someday I’ll post the source code online (once I clean it up a bit). If you’re desperate, drop me a note and I’ll email it to you.