Pegasus I, Pegasus II, Pegasus III, Pegasus IV, CF GPS Howto, #highaltitude Logs, Links, Ideas
Google Earth kml file here.
Launch and retrieval photos here
Full writeup soon
Pretty much ready to go! just waiting for a few things to be sorted out such as insurance. The launch should be within the next 2 weeks. A few changes to the payload:
Sorry for all the delay (nearly a month). I've passed all my exams which is good (means i don't have to come back in september to do retakes!) and also i've pretty much finished Pegasus III. A few suprises - the set up is now:
For the radio modem it acts as a serial port so i'm being dirty and literally pushing the last line of the gps.log through and then picking it up at the other end. Now these are only meant to be for 10miles LoS so we'll have to see what they are like, any data is better then usual.
The phone is the normal system and so will be reliable (i hope :-D)
Thanks to defy i've got a far better scripts to read off the gps which takes into account that the gps module actually only presents altitude every second (it refreshes position at 4hz) so often you don't actually get a altitude with gpsd. Also his script (written in perl) updates the gumstixs clock to the correct time (the lack of a backup battery resets the clock everytime the power is pulled).
At the moment everything seems to be working (after the flight I'll do a proper write up!) but i've got a couple of days to do some more testing and also get the final few bits such as phone credit.
A few pictures here
Though I have exams starting on Saturday i've made some progress...
Only a quick update, the lithium AAAs arrived yesterday (all 16 of them, though i'll only be needing 8 - 4 for the camera and 4 for the gumstix). Also have got off ebay a bluetooth dongle which I plan to set up to take the gps coordinates of my phone and log them on my laptop and then to open up google maps to display the location (also i'll get it to upload the coordinates to IRC #highaltitude so other people can follow).
Got my new camera which is really simple, 3.1MP - wired it up immediately and its all working fine. Luckly the flash doesn't turn on immediately so I'm going to leave it in place. Also the sim cards arrived so they have gone in to Pegasus and Bellerophon.
So this means that all that is left to get are:
So here is the complete list:
Pegasus IIIA few pictures here
Right the situation is that GPS now works, required a little hardware hack where i had to detach pin 19 from GND on the gps module and then attach a power supply via a 10R resistor (I got this from the NSSP VCC) (you could use pin 18 but i found it to hard to solder a connection with a resistor between two adjacent pins.
Am using the latest buildroot so 2.6.15 and also need to recompile gnokii after putting together a makefile for it
The camera arrived today but as I was taking it apart i stupidly shorted the flash capacitor out on something and it now doesn't work. Oh well you win some you lose some.
Right pushing ahead with Pegasus III, have got the gps working and have also linked up the phone to the gumstix. Have now got rid of the data cable and instead have Rx, Tx and GND directly from BTUART off the gpstix to the pins on the bottom of the phone. Therefore there is no need to change up to rs232 and i'm able to also not have the bulky serial connection. It also is much more reliable in regards to communicating :-D.
Also I have a new idea (its slightly crazy just to warn) = Bellerophon. Pegasus III will be carrying a secondary payload (called Bellerophon) containing at present just a nokia 5110 (though i have a spare GPS so perhaps something more). It will be attached by a cord to the bottom of Pegasus III's payload and will have its own parachute. Once Pegasus III reaches 10km the gumstix will initiate a cutdown device which will release Bellerophon to descend.
After launch a text message will be sent to Bellerophon's phone but won't get through due to the lack of reception. When Bellerophon descends low enough to get reception the text will go through and report back so we will know when it lands. Then using the GSM tracking service we'll be able to trace Bellerophon to within a mile.
At present this will allow us to know the direction that Pegasus is heading, also with a bit of calculation the time it reached 10km altitude and therefore rate of ascent. This will allow more prediction of area of potential landing.
Finally the plan is to launch Pegasus III at the same time as Nova 1. This means that if one fails we will know the rough location due to information from the other. It'll also make it easier to co-ordinate search and retrieval.
Will post pictures soon once I find the cable for my camera!
Still here!, though have exams in a month so progress will be slow.
The good news is that my gumstix has arrived with the new audiostix II board, i'll post details and pictures tomorrow. Meanwhile here is the list of parts:
Planned launch window starts on the 16th June from somewhere near Cambridge
Firstly sorry for the lack of updates recently - Pegasus III is still going ahead! Actually haven't made much progress yet as am waiting for my new gumstix to arrive. They are also going to send me an audiostix II daughtercard which has onboard GPS and will then just require an additional aerial. All that then will be required is a single serial port which I can connect the mobile phone to. Managed to get hold of another Nokia 6310i which I think I will use instead of the trusty Nokia 5110 brick (we seem to have a large surplus of old Nokias where I live).
Pegasus III won't test long range wireless, instead it will work on "perfecting" the GSM system after Pegasus II's failure. If the mission is successful I'll add wireless to Pegasus III system for Pegasus IV
Also instead of salvaging scraps of polystyrene to make the payload case I've been offered a customised case from the USA which I'm going to take up. Don't worry I'm not going to give up my DIY roots!
I'll update more once my gumstix arrives (which should be in the next 2 weeks)
Kindly gumstix inc. have offered to ship me one of their spare gumstixs to use in Pegasus III (so out goes the pda plan thankfully). This is going to be used as the main flight computer with either a serial gps or possibly the new audiostix2 which has a built in gps and then a mobile phone linked serially via gnokii.
The main aim will be make sure that the gps/gumstix/nokia system works perfectly with a few different functions. The main system will be the sms of Pegasus III's location every minute. I however am also going to have a system that every 30mins the gumstix checks the phones sms inbox for messages. If there is one with a particular command in the message then it dials up the internet (using gnokii software modem) and uploads the whole gps.log
Also going to look into the use of a cutdown system which works automatically if the payload strays to close to the sea. This could perhaps be achieved by mapping out an area of allowed co-ordinates and have the gumstix compare this with its actual position. If it is outside this area then it executes the cutdown mechanism and releases the balloon.
Finally while the gps/gumstix/nokia system is fine after the payload has landed it isn't sufficient for any extend missions so am going to explore different legal possibilities of communications. Am thinking of having a 802.11b Wireless router (probably a Linksys wrt54g running OpenWrt) with extended aerials perhaps even parabolic mesh dishes as described here. This could go as a second payload in the train attached to my spare serial gps (though it would require additional power...). Also using an extra antenna for the nokia it might be possible to mount this underneath the payload facing down which could extend the range of reception here.
Instead of using a gumstix and having to get it shipped from the USA and pay the extra shipping charge and VAT am going to try and use items I can get in the UK for under a total cost of £100 - Ebay here we come!
Thinking of going for 2 separate payloads in a train therefore keep the two things separate so that if one fails then the other won't...
Communications Payload: