I am deciding on a GPS module for taking readings up to an altitude of around 40,000m. As a ‘very’ begginer I am hoping to make full use of Sparkfun tutorials . I have identified the Lassen IQ as able to do the job but it is not mentioned in the “GPS Tracking Comparisons” tutorial or in the “GPS Shield Quickstart Guide”. Can it be used with these tutotrials?
“Trimble Copernicus - MUST be configured to work in AIR mode (thus will work up to 50000m), can be easily activated using Trimble Studio, or just sending one command, look at the datasheet.”
Which route would you recommend? Which GPS module and which tutorial…?
I am hoping to end up with the Google Earth representations as presented in the tutorial “GPS Tracking Comparisons” after retrieving the balloon. (wireless coms can wait for now)
I’m no aerospace engineer, but I have heard from my aerospace engineer buddies that the first thing to watch out for is temperature and not how many g’s the balloon experiences on reentry. Things get very cold the further from the ground something is, so GPS modules have a tendency to simply not do anything at low temperature. You won’t break it, it will just stop working.
Here is the flickr of one of the IT guys here at SparkFun who built a high altitude Balloon:
Try putting the GPS in a cooler with dry ice for about an hour and see if it still works, again, I’ve never tried this. Oh and you can find the specs for how cold the module can get in the datasheet and you can probably find the specs for how cold it is at 50000m. There are also a whole bunch of caps on how high a commerical GPS module can go, you just stop getting a lock after some altitude.
Anyone with more knowledge wanna weigh in on the subject?
Thanks for your reply. The payload will be insulated, that is no problem. Just trying to figure out which tutorial to follow for lassen or copernicus GPS assembly…
theg:
Thanks for your reply. The payload will be insulated, that is no problem. Just trying to figure out which tutorial to follow for lassen or copernicus GPS assembly…
I don’t think we have one for the lassen or copernicus, sorry.
theg:
Thanks for your reply. The payload will be insulated, that is no problem. .
The standard temperature for 40,000 ft is -70º F, simply insulating is generally not enough. Balloon payloads must be heated if you expect them to work for any reasonable amount of time.
I have a high altitude package that I designed around the APRS OpenTracker platform, a temperature stabilized VHF transmitter and the Copernicus for the high altitude balloon guys in Canada. We call it the RTrak-HAP (High Altitude Package). They currently have two units and have flown three missions so far with our tracker as the primary payload. I am working close with their head hardware guy, Barry, to make changes to the design, to better suit their needs. Things like on board pull up and pull downs are slated for the next revision and a few other minor changes. Barry has posted a very nice write up on the tracker here: http://bear.sbszoo.com/construction/tra … ak-HAB.htm
As for the Compernicus in Air mode, this is correct and I find that the Trimble studio software is the easiest way to put it in this mode. The Compernicus has a 3.3V TTL interface, so in order to talk to it, I have a cable I made up with an ST202 TTL/RS-232 converter in line to talk to it for programming.
Here are some pictures of the first gen unit they are flying right now:
