Sunday, 12 January 2014

Making of Santa Sleigh Test and update for 2014

We were truly blown away with the positive response and media interest that our Santa Sleigh Test video gained. It all happened as a bit of a whirlwind, from turning up on the BBC One O'Clock News  then again on ITV's evening news, to an appearance in the Daily Mail, Metro and Daily Telegraph newspapers and their respective websites. That was just the UK, so far we've also found coverage on websites in Canada, USA, Mexico, France, Germany, Netherlands, India, Venezuela and Australia. You can find one of our personal favourites here, with the bemused presenter slightly struggling with our name. Unbeknownst to us, we've also gone from a two person team to a full on research institution. Crikey.

Artist's impression while 
we were in the planning stages.
Having a trial run, trying to see
what the footage could look like! 
 It's all coming together.

What was great was how kind everyone was about the video, taking it in the manner it was intended - as a bit of festive fun. Finally, thank you to all those who shared in our excitement by getting in touch via email and social media and their positive response.

Getting setup for launch.
As this launch was a bit different to all of our others, we thought we'd create a 'Making Of' video, to explain how we did it and cover the real launch itself.

Santa and Rudolph's journey. 

Plans for 2014

We've got a few potential projects in the pipeline and are busy following up on these, hopefully they'll lead to a productive and fun-filled beginning to 2014! One initial thing on the to do list is a launch with a dedicated 'Balloon Cam' to try and capture how the balloon changes through the flight - from launch to burst. Watch this space for news on STRATODEAN Four!

Monday, 16 December 2013

Santa Sleigh Test (STRATODEAN Three)

Here is our slightly silly video for Santa's Sleigh Test (STRATODEAN Three), launched on the 1st December 2013.

Merry Christmas!

The payload was recovered on the outskirts of Yeovil, thanks to all who helped track. 
Full write-up and launch video to follow. 

Sunday, 1 December 2013


Thanks to all who helped with today's flight. Santa and Rudolph have been recovered and we've got a lot of footage of their voyage to go through!

We're taking a bit of time to try and put it together into a video, something a bit special ready for Christmas - so please check back soon or follow us on Twitter for more frequent updates.

Ho Ho Go

We're off, for those wishing to follow the journey, track here:;STRATODEANQ_chase

Also we'll be updating Twitter here:

Saturday, 30 November 2013

Twas the night before Launch Day...

Final preparations are underway and we are all systems go, ready for our STRATODEAN Three launch at approximately 10:00am tomorrow. Please see here for radio tracking information - if you just want to follow it on a map please see here! You may have noticed that this latest launch has a distinctly festive theme with a few famous faces on board. Therefore we really appreciate all your tracking help, fingers crossed for a successful flight and retrieval! Don't worry - Rudolph is getting an early night.

The wearing of Christmas jumpers whilst tracking STRATODEAN Three, aka Santa Sleigh Test, aka STRATOSanta, is fully encouraged.

Monday, 25 November 2013

Santa's pre-Christmas sleigh test

OK so the first planned date of this launch didn't go well after a mix up with the CAA and our approval for launch. This was certainly disappointing, however truth be told we were a little short on time to put all the finishing touches to the payload - so this could be a blessing in disguise. We used the time this weekend instead to make improvements! We have also made the brave decision to tell you all about it before we launch! :)

So it's November 25th and with a month to go, Santa and Rudolf have just been finishing off the modifications to their 2013 sleigh. Like all good engineers, Santa has opted to test the new changes before rolling it out into production and he has come to STRATODEAN for help! (It's been a very well kept secret that we provide technical facilities to all our famous mythical friends. The Tooth Fairy and Easter Bunny are already well established customers.)

He gave us a clear project remit - for us to take him up and down on our payload to allow him to test the new handling abilities of his sleigh. Apparently the cost of reindeer propulsion (magic flying dust) has skyrocketed in the last few years and he can only justify the once a year purchase for Christmas due to Mrs Clauses' bingo habit and the increasing Elf wages. Furthermore, for this test he can only bring Rudolf as the other reindeer are getting on a bit and they need to save their knees.

We drew up a plan -
STRATODEAN Santa handling test v1
Who else has a whiteboard in their dining room? :p
So the plan is simple, get Santa and Rudolf to the stratosphere, let them test their 2013 sleigh modifications, record the test and finally ensuring they get home safely as they have a job to do in a month - no pressure then!

Thursday, 21 November 2013

Potential Launch of STRATODEAN Three this weekend! - POSTPONED

Potential STRATODEAN Three launch this weekend, as always - weather dependant! This will be the first use of our new tracker also.

This launch has a planned festive theme for video coming in December. Ho-Ho-Hope you like it! Trackers always appreciated. Tracking info can be found here.


Unfortunately we have had to postpone this launch. Will update when we can, we'll have more info on Monday.

Thursday, 31 October 2013

Happy Halloween!

Happy Halloween from Team STRATODEAN!

Spooky HAB and friend

Saturday, 5 October 2013

Our photos - Helping the community

A few months ago we were asked if it was OK to use some of our overhead photographs of the Forest of Dean from our first launch. The request came from Design and Purpose who had been tasked with creating the literature and promotional material for the Berry Hill, Five Acres and Christchurch Neighbourhood Development Plan. This is an important document that is being put together by members of the community in order to have their say with what happens to the local schools, college and leisure centre amongst other things such as future housing development. It was great to get involved and we think the end results look impressive! If anyone else in the Forest of Dean area has any other project ideas or proposals, please get in touch!
STRATODEAN Berry Hill, Five Acres and Christchurch Neighbourhood Development Plan
Berry Hill, Five Acres and Christchurch Neighbourhood Development Plan

Sunday, 29 September 2013

The Second GPS Tracker

When we started the project last year, the aim was always to get that infamous picture of the Earth’s blue haze and to say that we put something into near space – at the time, the method and technology was thought of as a means to an end. It didn’t really matter ‘that much’ how we did it, just that we did. However as we got more into the project and, after the second launch had issues with getting GPS lock, I decided it was time to improve the GPS tracker and make it ‘my own’. Using the prebuilt breakout boards and the Arduino Uno was definitely the way to go when we started out with personal electronic devices – it meant that the harder, unfamiliar electronics work had been done already. Therefore it was just a case of programming, based on the sample code, in order to get it working. I was, and still am, really proud of the first tracker, but I knew there were definitely areas that could be improved:
  • It was comparatively quite big and heavy, which ultimately meant that we needed more space and helium to take it up.
  • It took too many batteries to power it.
  • It was very much a ‘prototype’, where the components were soldered on to strip board – not always the most reliable method.
  • It was not very robust – we were always scared of dropping it – or it breaking on landing.
After speaking to a few guys on the #HighAltitude IRC channel, it became apparent that the best (and most fun) way of creating a new tracker would be to design my own in CAD and have my own circuit board created… so that’s what I did!

Designing the new tracker

The first thing I needed to do is work out what I wanted to achieve with the new tracker. If you aren't familiar with our first tracker, have a look here. I identified a few key areas:
  • Must be under 100g.
  • 3 or less AA batteries.
  • Look a lot more ‘professional (!)’.
  • Be a lot more robust.
  • Future-proof – with the ability to add additional features at a later stage.
STRATODEAN Designing the layout in Eagle CAD
Designing the layout in Eagle CAD
The second thing was – how do I build it!? It was at this point I managed to get some really helpful hints and tips from Chris Stubbs on IRC (chrisstubbs) on using the Eagle CAD software, and ensuring that my circuit would work! Chris has produced some really good tutorial videos on how to use Eagle – you can see them here and here.

The idea of Eagle is first to create a schematic. This is basically the circuit in block form, showing the logical connections and providing an overview of what is joined to what. Once you are happy with your schematic, you then move into the physical ‘view’ where you can then decide where on the finished circuit board the components will end up. Having not done this before, I found it quite time consuming but really enjoyable to work towards a finished board.

It was at this time that I had to make a decision on the form-factor of the components. On the first tracker I used ‘hole-through’ components – those that you have to poke through the board and solder on the other side. My third requirement above however, said that the new board needs to look more professional – so for this reason I decided that the best (and more challenging) way would be to use ‘surface-mount’ components. These, as their name describes, are soldered directly onto the surface of the circuit board and give that ‘made by a machine’ look. I knew this would test my soldering skills but I just went for it.

Circuit and components

Because prototyping on a breadboard has been known to introduce more problems than there would actually be, I took some advice and decided to create the board, have it checked and then hope it would work when I soldered it – a little risky but it had worked for others before, so I hoped for the same! I already knew I would be getting the boards from Hackvana for a very reasonable price, so it was a risk I was willing to take if I had to change the board because of some unfixable problem.

STRATODEAN Main components of new tracker
Main components of tracker
This circuit is designed to run off a minimum of 3AA batteries, but can run up to 6+ (if the additional external components require it). It does this by using the LP2992 voltage regulator, which takes any input voltage between 4v and 16v and outputs 3.3v. There is an error with the above diagram. I had mistakenly connected the bypass directly to ground, instead of through a capacitor to ground. Initially this was giving an output of half the expected voltage and took a little while to debug. The resolution was to simply disconnect the bypass altogether from the circuit, by cutting the leg off the regulator.

I decided to stick with the same microcontroller as in the first tracker, the ATMega328. This was because I was already familiar with this way of working and coding, so wouldn’t have to relearn this element. The other key components were also familiar – the same NTX2 model as before and the uBlox GPS chip, although this time using the upgraded Max7C which promised better power consumption. The GPS antenna also remained the same Sarantel brand as before, though this time a different model than was found on the previous breakout board. I later learned that Sarantel have gone into administration (at the time of writing), so I guess stocks of this antenna will soon diminish – will have to keep an eye on this. The same one-wire DS18B20 temperature sensors were included, I mounted one directly on the board and ensured I had a connection for the same external probe as on our second launch. Finally I included a micro-SD card reader to record our data as before.
For our next launches, we wanted some way of moving the camera or an object in near space. To do this I have made previsions to allow for a servo to be connected, with the power being delivered through a MOSFET to allow us to turn it on and off to save power.

Olimex ISP-500 AVR
Olimex ISP-500 AVR
When creating the first tracker, the interface with the computer I was using to program this was very straightforward – the USB lead from the Arduino Uno. In order to program this new board, I had to implement a different method – ‘In-Circuit Serial Programming’ – ICSP. For this to work, I purchased an Olimex ISP-500 AVR programmer from eBay, which would work in conjunction with the ICSP header on the board. One tip for the capacitors and resistors is to buy a sample book, which has every value you need – I got my one from eBay, posted from China. After a little configuring, programming the board was done in much the same way as before.

Soldering the new board

New boards!
Once I had received the fantastic new boards from Hackvana, it was then necessary to start soldering. The components were either ordered as manufacturer samples, or from eBay and HAB Supplies. I had done a fair bit of soldering in the past but never SMD. To research and get some knowledge on how to do this, I looked at these YouTube tutorials. As long as you have the right tools (small soldering head, small gauge solder, tweezers and flux) and take your time, soldering SMD components is a somewhat satisfying experience!

New code

The code from the first tracker was not ideal, it did the job but was not very refined and I knew many improvements could be made. I decided that if I was making new hardware, then the software would get the same attention. The main thing to improve with the first tracker was the fact that it was doing everything sequentially – looking for a GPS position, processing it, sending it over the radio, repeat. After some research I and talking with some people on IRC, the concept of ‘Interrupts’ was brought to my attention – they are fantastic! The idea is that you can set up a scenario where two portions of the code can be run at the same time. To do this you create your main repeating chunk of code in the loop, but at the same set up ‘timers’ which then ‘interrupt’ the main flow of code to process some other code, while continuing with the main flow. For our purposes, the GPS data receive and processing is the main body, while the radio transmission is our interrupt element. This has improved the reliability of the code no-end and I really do recommend trying to use interrupts instead of the delay code. You can see the basic working GPS and radio code on my Github code repository.

The finished tracker

STRATODEAN Second Tracker
The New Tracker
So here it is - I hope you agree it looks a lot more professional than the first one! We are very proud of this new tracker and can't wait to launch it.  It is 100g lighter than the first one and runs off 3 AA batteries so saving both weight and power. I have connections on the left for power, external temperature and two servos if required. Also included is the micro SD card. I haven't gone into too many technical details here, but if you do want to find out more, please drop us an email

We look forward to flying it soon!