Sunday 26 May 2013

STRATODEAN Two

Here's our video of STRATODEAN Two - don't forget to view in HD and that you can pause the video if you see something interesting! The photos are at the bottom of this page.


Saturday afternoon saw the launch of our second high altitude balloon. There was less build up for this one and to be frank we weren't initially planning on launching again so quickly, but an opportunity presented itself and we just decided to go for it.

We decided so quickly, we almost surprised ourselves. There were a few factors which played a part:
  • we were still in possession of a half full jumbo tank of helium just begging to be used
  • the nice man at the CAA had given us approval and it would be rude not to use it
  • that GoPro video camera lens fogging incident first time round was rather annoying and we still felt like we could get better images and video
  • the launch predictor was showing an unusual flight path doubling over our hometown and then making its way over the picturesque Brecon Beacons
  • family members who were unable to make the first launch wanted a repeat so they could see a bit of the action
So low and behold, we found ourselves at the local recreational ground once more, ready for launch. You can read a little more about the amendments we made to our payload and tracker here, everything thing else pretty much stayed the same.

Our launch preparations were delayed slightly by a slight tracker hiccup; it was connecting to the GPS and uploading our location correctly but the signal was unreliable, dropping in and out. We didn't want to risk launching without a firm satellite fix so this set us back around 40 minutes.

As you will see, it wasn't exactly clear, blue skies but due to this we actually managed to capture some interesting cloud formations.

STRATODEAN Two Sitting down on the job
What's this, sitting down on the job?!
STRATODEAN Two Walking out to launch
All systems go! Walking out to launch.
STRATODEAN Two between cloud layers
Sandwiched between two cloud layers.
You can view our flight path below. Whereas our STRATODEAN One chase primarily featured worrying about how we forgot to attach our contact details label to the payload, this time round it was characterised by a distinct lack of mobile phone signal. 

STRATODEAN Two Flight Path
STRATODEAN Two Flight Path
We said hello (and swiftly goodbye) to 3G around the Abergavenny area and from that point on only had normal mobile phone signal at intermittent intervals. Our three networks (O2, Vodafone and Virgin) all failed us! Whilst we remained in good contact with the tracker and were consistenly receiving altitude and location data,  our lack of 3G meant we just weren't able to decipher these coordinates. This meant having to rely on good old-fashioned map books and calling friends with Wi-Fi back at home. Turns out spelling the names of remote Welsh areas on a crackling phone line is more difficult that you think, two of our favourites were: Coed Aberllechach and Llanddeusant.

Apologies to all for our lack of contact on the UKHAS chat and Twitter - believe us it was very frustrating! While we were struggling for any type of signal, our colleagues in Chase Car Mini had 3G (lucky duckies!) and were quite happily tracking away using their network of choice '3'. Their tracking ability ended when the HAB tracking community lost contact due to the mountains breaking their line-of-sight at approx. 2500 feet. Shortly after the payload had landed, when we miraculously had signal, we managed to rendez-vous with Chase Car Mini and use their 3G to look up our up-to-date GPS coordinates from our SDR receiver. It had landed in a field of sheep, conveniently right next to the road and only two minutes away.

We recovered the payload approx. 15 minutes after landing. As the location was so open and accessible, with better 3G infrastructure we think we would have actually been very close to being able to watch it land! The dream of catching the payload (or more realistically, being hit on the head by it) as it falls from the Earth's atmosphere lives on...

STRATODEAN Two Sheep
Locals are unimpressed with our parachute.
Team high five - Cassie putting in a little more effort than Mark.
We have picked out some of our favourite photos from the on-board still camera below. Be sure to check out more in our album at the bottom of the page. As well as the Earth, there's some nice pics of the Brecon Beacons, a reservoir and even some sheep. Yippee. We were a lot happier with these images and with the side-mounted camera picking up the curvature of the Earth.

STRATODEAN Two
Camera pointing south, the two bodies of water
are the Bristol Channel and English Channel.
STRATODEAN Two
Nice sunny day up here! Our sensors showed that the temperature dropped to its lowest -31C at 11000m and then rose again to 6C at time of burst. 

STRATODEAN Two
Aeroplane trails crisscrossing into the clouds.
This area is the primary flight path from Heathrow to the USA.
STRATODEAN Two Moon
That little white dot is the Moon.

As mentioned above, one of the driving factors for a quick second launch was the misting up of our GoPro camera first time round. The below pictures are a clear example of the difference made by removing the plastic protection over the lens, which prevented any condensation forming. We were much happier with the improved colour definition and image quality.

STRATODEAN One GoPro Video
Still from our STRATODEAN One GoPro Video.
STRATODEAN Two GoPro Video
Still from our STRATODEAN Two GoPro Video.

What we learnt this time round:
  • For all future launches, '3' is the dongle network of choice
  • Clouds are interesting
A special thank you to Matt, our official Team STRATODEAN photographer for the day.

No, the cameras aren't all his.
Canon, if you're reading this - please sponsor us with a super duper lens. Cheers.
STRATODEAN Two Job Done
Job done.

Friday 17 May 2013

Our second launch tomorrow!

A very quick post today confirming we are preparing for a launch tomorrow afternoon - although as always, weather permitting!

As a quick summary we've:
  • Added two temperature sensors to monitor the changes both inside and outside the payload. 
  • Installed the still camera (previously used pointing downwards) into a side position for more horizon photos.
  • Removed the lens cover from the GoPro camera so as to hopefully avoid the fogging as seen on the first video.
This launch follows quick on the heels of our first as we are still within our balloon helium hire and are able to use our original spare balloon. The weather predictions have been prohibitive until very recently so we want to pounce while the opportunity is there.  

Any assistance with tracking would be much appreciated by fellow HABers. Tracking details can be found on the UKHAS site. It's looking like a potentially interesting recovery in the Brecon Beacons (hiking boots at the ready!).

Tuesday 7 May 2013

STRATODEAN One Follow-up and Future Plans

As promised, here are some of the stats and data we've gathered from STRATODEAN One. We launched on Sunday 21st April at 10:14am from our local rec in Coleford.

We listed our flight on the UKHAS Google Group in the few weeks prior to launch so we had lots of people willing to help track. See below for a break down - thanks to all those mentioned!

STRATODEAN One Trackers
People tracking our payload

We were forced to stop our own in-car tracking to save the laptop battery (in-car changer blew a fuse!) so your help was essential for us to keep an eye on the balloon trajectory and predicted landing site.

STRATODEAN Signal being received
Signal being received
Some of the most positive feedback from our flight was that the signal did not drift off frequency. In real terms this means that our radio transmitter kept very close to the advertised 434.650MHz and was not adversely affected by temperature. This also meant that tracking was easier as radios did not have to continually be retuned.  We received a nice email from new 'HABer' Martin Rigby who was kind enough to show us a screen shot of the signal as received by his radio in Penrith, Cumbria. You can see that the RTTY lines are fairly straight.

We also had an email from fellow HABer Geoff Mather who was able to create this interactive flight movie in Google Earth based on the telemetry that we had been transmitting. Thank you Geoff!

The raw telemetry that was saved onto the SD card from the transmitter can be seen here.

Since the launch we have put things on the back burner for a week, just to reflect on what we have achieved and to think about a few other (non-space!) ideas. However, it's now time to start resetting ourselves and the project and working out what we can do better for STRATODEAN Two!

In our second launch we'd like to do a few things differently. The first launch was a success but there are some improvements to be made. Firstly we aren't entirely happy with our video quality when the payload reached the stratosphere. We included the GoPro anti-fog inserts thinking that this would help us avoid the misting in our videos, however we now know this caused the exact opposite to happen. The waterproof case let air out but did not let air in, so a vacuum formed inside. As we all remember from our science lessons(!), water boils at a much lower temperature inside a vacuum, so inside our case, the moisture that had been collected by the anti-fog inserts started to boil and then condensed on to the coldest part of the case - the lens cover pointing out into space!  To remedy this we are simply going to fly without inserts or a lens cover and have holes in the case so that no vacuum can form.

We had no idea from the first launch how hot/cold it was up there, so another thing that we have acquired are temperature sensors that we can wire into our flight tracker so that it will record these values for us.

Finally, something we are trying to research for next time is adding time, velocity and altitude data to our flight videos - currently a work in progress trying to find the best software. We had people comment on the video 'how high are we now' at certain points, so it would be nice to have a little 'Head-Up Display' on the video to display this data.

We have applied for CAA approval and extended our helium rental so it's just a case of completing our upgrades and waiting for good weather!