In the past, I usually carry both my iPhone and iPad on chases. The iPhone offers navigation and tethering whilst the iPad offers a longer battery life than the laptop – useful for checking on the location of the balloon mid-flight. However, the spacenear.us tracker doesn’t run at all well on touch screen devices and this has somewhat prohibited using iDevices to track flights.
Coupled with this fact, I have always wanted to write an iOS app. I looked into app development just over a year ago but backed away after seeing how complex the code looked – certainly different from the C code I was learning. In the past year though, I have done rather a lot of programming. Initially learning the concepts of Object Oriented programming via a Java module in first year at University and then taking another more advanced Java module the beginning of this year (only to come out with 98%!). Having looked a quite a few languages over the past months, Objective C certainly didn’t seem as daunting as it once did. I was ready to give it another go.
I decided to create, as my first app, a high altitude balloon tracking app – rather ambitious! Just a few weeks after diving into Objective C and Cocoa I had my first prototype, and it worked rather well. I had turned my iOS devices into useful chase tools. Subsequently bundling in a ‘payload locator’ feature and chase car tracking (uploading position of chase car to spacenear.us tracker) it was now a HAB hub for iOS.
Feeling rather pleased having used knowledge of Java and OO concepts to quickly learn Objective C and then creating something that was of real use, I was keen to share it with the high altitude community. Given the community mostly comprises of Android users (I have had many a lecture about how Androids are far superior) I was sceptical as to how many people it would actually benefit – I thought, at most, 10 people would benefit. Turns out I was wrong – as of today over 35 people have downloaded the app! It’s available on the App Store under ‘HABHUB’ for both iPhone and iPad.
Having seen Dave Akerman’s chase car setup and, from past experience, finding it hard to track the balloon in-flight without an experienced HABist sitting in the passenger seat feeding locating and predicted landing updates, I wanted to put the HABHUB app I built to good use. Consulting Dave as to the best tablet in car mounting option, he recommended Brodit tablet mounts. After speaking to the great people over at Clove Technology they loved the project and sent me a free iPad mount – a big thanks to Clove!
I was eager to install it so this morning I set about the very fast and easy installation (Brodit make mounts unique to each car make to ensure a secure fit). Within minutes I had it secured onto the mini’s somewhat small dashboard.
After popping the iPad in and booting up the HABHUB app it quickly became apparent that it was going to be extremely useful during a balloon chase. Sitting at the right height and orientation to quickly see location information and plan the chase! Now I just need to get around to launching a balloon.
Hopefully not too long a wait as I have a couple of launches coming up soon, including the long-awaited HABE Lab flight. Stay tuned..
It’s been a while since I last updated the blog.
Since then, the new flight computer pcb (printed circuit board) has been manufactured and two boards have kindly been soldered up by Anthony Stirk. They are looking great – at just approx 3×3.5cm they save on space too (which will be vital in the HABE Glider).
I am currently testing them out with code and hope to fly them both soon.
For a while I have been meaning to set up the CUSF hourly predictor. Yesterday I got around to installing it on my linux (Ubuntu) server – didn’t take too long but grabbing the wrong files initially didn’t help. It is now up and running at http://panther.acudworth.co.uk/hourly. It shows predictions for up to 180 hours in the future (obviously closer to the current time will be more accurate), helping to get an idea of when best to launch.
Having not done a launch since last October time I am certainly ready for another! There are however many things to sort before the next launch. My next flight (HABE 7) will be a purely experimental flight – testing out systems that will be used in both the HABE Lab and HABE Glider missions. Some of the features I’m working on for the next flight:
- Testing of the new flight computers.
- Dual payloads, each with their own tracker running on different frequencies to avoid downlink radio clash.
- Mid-flight separation using a pyrotechnic cutdown module, one payload will carry on ascending whilst the other one falls back to earth via parachute – this will be required for the HABE Glider mission.
- Uplink test – this requires syncing up downlink transmissions between the two payloads as to allow a brief ‘quiet’ period for the uplink transmission to get through. This is probably the most ambitious bit of the flight.
- Extending cameras out on a boom so they face inward, looking at payload(s) with the backdrop of Earth/Space.
I will be using a Pawan 1200g balloon, hopefully this one won’t fail on me @ 23km in altitude like the last one did. Hydrogen will most likely be used instead of helium due to the significant increasing cost of helium (that will be a first for me). New parachutes will be tested – old one that lasted 6 missions is stuck in a big tree!
Whilst I have been busy over the past few weeks with University work, work has continued with various bits & pieces. A brief summary below:
The response so far has been very positive – many schools have been in touch and expressed an interest in sending experiments up to near space on board the HABE Lab, especially primary schools. Hopefully this will inspire the young children to think differently and dream big! I am still looking for more people to get involved so if you’re interested, or know someone who would be interested please register interest here.
I’m in the process of building the system that will allow people to book slots on the first mission. I hope to have this completed asap; those who have registered interest will receive an email when the system goes live. You’ll be able to specify location preference (inside and insulated or outside and exposed) for each experiment. Keep an eye on my twitter: @adamcudworth for more updates about this…
HABE Flight Computer v2.0
After many stressful hours using Eagle (CAD software for designing PCBs) I have finally completed the next major version of the flight computer! Almost everything is different about this version compared to my last version – everything has shrunk in size: smaller resistors, smaller GPS module, smaller radio module which is capable of uplink too (with some work), smaller microprocessor… The end result is a flight computer/tracker that is just 3×3.5cm – a tiny bit bigger than a 10p coin. I would like to say a big thanks to Anthony Stirk for helping me out with various aspects along the way.
This new board will replace the old 5x5cm board (seems big and bulky in comparison!) for use on future flights including the HABE Lab and HABE Glider, forming the main track and control mechanism for the flight. One of the most exciting features is the new radio module; being a transceiver it supports receiving as well as transmitting. Using powerful uplink radios on the ground it should be possible to send commands to the balloon in flight – a major improvement.
The final PCB design is below (yes, it was a nightmare to route the various tracks – it is all done manually). I will upload some photos when the manufactured board arrives.
Now that I have a few minutes free here’s what happened during the day:
The first thing I noticed after waking up was just how windy it was on the ground outside, in the past I had carried out a launch in reasonably windy conditions and it proved difficult so I was concerned whether I would be able to get it underway. After packing the car with radio equipment, chargers, duck tape, batteries (can never have enough batteries in the chase car!) etc, I headed off to the launch site – only about 150m down the road.
I arrived about an hour before I planned to launch as in the past I have ended up underestimating the time it would take me to set everything up. Out came the ground sheet to protect the balloon from the stones on the ground during filling – it actually proved difficult to get the ground sheet pinned down due to the wind – at this point I really began to doubt whether I would be able to get the balloon filled and launched successfully. Fortunately help was on hand, another “HABist” who lives close to me in Worcester (Will Duckworth) came along to help out with the launch; also a few friends and family joined in.
After I had rigged up the payload (the box that contained all the equipment), powered on the radio tracking device I had built and checked I could receive and decode the telemetry via the laptop, the all clear to begin filling the balloon was given. As expected, filling proved extremely tricky due to the windy conditions, despite the many hands trying to keep the balloon in one position it bounced around all over the place, narrowly missing the ground on a couple of occasions. Once the balloon was filled, I quickly switched on the gobandit video camera and initiated the script on the Canon A570 camera to capture stills. I popped the lid on the payload box and tapped it up (duct tape is probably the most useful thing in HAB – solves almost every problem!) then proceeded to slowly let the balloon out on the string. A brief lull in the wind allowed me to launch – off it went, just missing a nearby tree!
Fortunately everything was working as it should – telemetry was being received and decoded successfully by the in car laptop. By the time I had packed everything up from the launch site it was already over 1km in altitude and about 10miles away. I took along a friend in the chase car – always a good idea to have someone else in the car operating as a ‘co-pilot’ – we immediately headed off towards the predicted landing site (approximately 35miles away).
It took about an hour to get near the predicted landing, at this point the balloon was around 25km in altitude and still ascending at a rate of ~5m/s. I was expecting a burst around 31km in altitude so pulled over at a service station and grabbed some lunch. Returning to the car we were surprised to see the balloon was still ascending and about 33km in altitude! Could this be a new altitude record for me?! I spoke too soon.. a few minutes later (at ~14:15 UK time) the balloon burst and the payload started plummeting back to Earth, reaching speeds of over 150mph initially due to the lack of atmosphere.
Time to mobilise – with about 30mins until landing it was time to head closer to the predicted landing site and see if we could get a visual when it came through the cloud layer. I’ve only ever been able to get a visual on 1 payload descending before and that was one of Will Duckworth’s a few months back, it’s very tricky to get in the right place as landing predictions often change around within a mile or so due to varying wind speeds at different altitudes. After scouring Google maps, we decided on a location that was just off a main road – what the satellite view did not show was a huge ditch filled with water! Put it this way.. I was fortunate the car survived the escapade. Unfortunately the landing prediction changed at the last minute to a location about 700m away, despite scanning the skies in search of a box falling by parachute we were unable to see it.
Confirmation came through over the radio that it had landed and after a short drive and about 10mins walking through farmer’s fields HABE 5 was recovered!
The payload had no damage apart from the straw antennas bent and the balloon burst cleanly leaving only a small amount left. When we recovered it the camera was still taking photos! At this point over 1000 photos had been taken – I was surprised the batteries were still going strong. We collected up the remnants then headed back to the car. First thing, get the SD card out the camera to see the photos! It took a while to scroll through the many 100s of photos but wow – as the altitude increased the photos just got better. One of my favourites below (taken at 33km in altitude over central England):
A selection of the best photos can be found in my Flickr set. The gobandit video camera also captured some good footage however it fogged up considerably at higher altitudes due to moisture trapped in the lens casing. I will fly the gobandit again this time with an antifog accessory that gobandit are sending me. The footage captured near the ground however was very clear – all in all a great product, it’s not everyday that you send one up to near space!
A final note – I’ve been surprised just how worldwide the coverage of HABE 5 has gone! Many people have got in touch either via email or twitter - thank you all for your great comments, it has been really good to hear from people all around the World. If you haven’t got in touch – feel free to, I’ll try and respond as fast as possible!
Stay tuned for future launches coming soon… (best way to keep up to date is follow my Twitter: @adamcudworth)
I’ll get around to writing up what happened on launch day with HABE 5 sometime soon – photos here. In the mean time here’s some of the worldwide media coverage it has received (much to my amazement!):
CNN – aired on CNN 3 times so far
Live on ITV (in the studio)
BBC Midlands Today
- ABC Radio Melbourne, Australia
- ABC Radio Perth, Australia
- BBC Radio Nottingham
- BBC Radio Hereford & Worcester
- Hermitage FM
Thanks for all the great comments.
It’s been ages since I’ve updated the blog, so here’s a quick look at what I’ve been busy doing on the HAB front.
Whilst I haven’t launched a HAB solely for my own purpose since HABE 2, I have launched 2 HABs for others – documented below:
HABE 3 – Launched April 2012
This was a launch with Lee Kern for a new Channel 4 production. As the program is yet to air I can’t say too much. Inside the payload there were 3 GoPros that captured some fantastic footage (1 pointing up at the balloon, 1 pointing down at Earth, 1 pointing at…..top-secret….. (horizontally).
There were some issues with the tracker during the flight. I had knocked together a “pico” – tiny, lightweight (just 30g) tracker which consisted of a uBlox 6 GPS module, Arduino Pro Mini (thanks to RoboSavvy!) and an RFM22B radio module (thanks to Proto-Pic!). I opted for a small ceramic chip scale antenna for the uBlox 6 and as a result the signal wasn’t comparable to the strength of a larger sarantel antenna. Straight after take off the altitude froze at ground level indicating a lack of 3D GPS fix however the altitude was reported correctly after approximately 30mins. Then, the whole GPS decided to cut out completely at around 18km in altitude so I had no location for the payload whatsoever – nightmare considering this payload contained 3 GoPros worth over £600! Initial thoughts were that the uBlox had failed to be set in the correct mode on startup meaning that it had cut out >18km due to the CoCom limits. Yet, fortunately this wasn’t the case as it came alive again around 25km in altitude!
The rest of the flight was a keep the fingers crossed moment – with the GPS fluctuating from a 3D fix to a 2D fix to no fix at all, I hoped it would work on the final part of the descent so we could locate it on the ground. Fortunately – it landed with a 2D fix! Turned out to be very lucky as the backup SMS based tracker didn’t have signal where it landed so more than likely the payload would have been lost.
After some off-roading and help from fellow HAB enthusiast Dave Akerman we found the payload lying in a farmers field about 800m from some track. A successful recovery – much to the delight of the TV crew (and myself)! After a brief look at the footage, the SD cards were handed over to the TV crew and I await the best bits on Channel 4 very soon…
HABE 4 – Launched August 2012
When I was scouring the UKHAS mailing list back in June I came across a post written by Josh Taylor who wanted help to launch his next idea “Space Art”. He had done 1 launch previously with the help of a few other UKHAS people and clearly loved it as he was coming back for more. This time, I decided to help him achieve his goal.
He wanted a tracking solution so he could track his payload as it flew over the UK and then hopefully recover it successfully. Since early this year I have been designing and building with the help of Anthony Stirk (a fellow HABist) a custom flight computer PCB. After many many redesigns on Eagle (hardwork!), I sent the design files off to the factory in China to turn make 10 5x5cm printed circuit boards. A little over a month later they arrived – after destroying an expense uBlox GPS module due to my poor soldering I took up Anthony’s offer to solder it all up for me – what a great decision as it came back perfectly soldered – thanks Anthony! I’ll do another post sometime soon detailing the HABE PCB as it has quite a lot of tech packed into a 5x5cm footprint – it’s quite awesome.
Josh’s flight offered me an opportunity to test out the new HABE PCB, so I offered my help and after exchanging a few emails to sort out what we were going to do etc we were all set.
The launch day was nice and sunny (big surprise given the recent UK weather…) and the preps went smoothly. I strung my tracking payload containing the HABE PCB onto the “chain” of payloads and off it went to the edge of space. Inside Josh’s payload was a GoPro pointing down at a canvas where “Space Art” was being created – more details of that over at his blog. The tracking of the flight was flawless this time, everything worked great. We managed to get ahead of the balloon and were in a prime position near the predicted landing site. We were almost bang on with the landing site after moving locations a few times – unfortunately we couldn’t get a visual on it coming down. After receiving confirmation over radio that it had landed we moved in to retrieve. Once again, it was positioned in the middle of a farmers field and after trekking through some 10ft sweetcorn we spotted it in the adjacent field – my 4th successful recovery!
Despite my initial doubts that the “Space Art” canvas might get destroyed by the winds at altitude it was intact and looking great on recovery. We made our way back to my house where we reviewed the GoPro footage… wow.
Keep an eye out on Josh’s blog (and the TV..) for the footage!
Following last Saturday’s successful flight of HABE 2 and the new addition of a “black box” style SD flight logger I have collected a wealth of data. Having spent some of yesterday writing a C command line program to parse through the log file, earlier today I managed to extract the information and pop it into an excel spreadsheet.
Having plotted some fancy graphs etc the results where fantastic. All of the graphs offer a unique story and contain lots of useful information – a great success. I’ve decided to distribute the excel spreadsheet containing all the raw data and graphs etc so people can have a look at all the information. It may prove useful to some. The excel workbook can be downloaded here (xlsx) and an older (xls) version here.
I’ve posted the graphs below for all to see:
A few brief notes on the graphs:
- The temperature graphs have the ascent on the right (slightly warmer) and descent on the left (slightly cooler).
- It can clearly been seen that the coldest temperatures faced reside in the 10-12km altitude bracket. As the balloon rises above this altitude it actually gets warmer contrary to popular belief! The science behind this: the upper layers (stratosphere) absorb UV radiation far more efficiently than the lower layers, therefore this acts as a heating effect – it also prevents extreme UV readings on the surface of Earth.
- The solar panel readings are extremely interesting and probably contain the most information. On initial observation I didn’t see that much information, but on closer observation there is a lot said. Firstly – why the mass scatter of points everywhere?! Well, I believe this is due to the swinging of the payload (due to winds); as the solar panels were mounted on top of the payload and the sun was relatively low in the sky (Winter), this would have caused differing levels of light falling on the solar panels, indeed at some point they were probably in shade hence the many near 0v readings. Secondly you may ask, ok, why isn’t that the case for the lower altitudes (<10km)? The answer to this – the payload was in the clouds through this part of the flight. Clouds act to diffuse the light from the Sun and therefore are bright all around inside them – so whether the payload was on it’s side or pointing upright the light falling on the solar panels was much the same. On close inspection (you made need to download the full quality versions – excel workbook) the readings seem to fall into rectangles at lower altitudes – I believe this is the case because of the different cloud layers. From the photos taken by the onboard camera it’s clear that there were multiple cloud layers and each layer would’ve had unique properties – hence differing voltage/power constraints. Interesting!
I have annotated the first altitude vs SP1 voltage graph illustrating the different “rectangles” – take a look:
I’ve also done the customary 3D Google Earth plot of the flight path. You can download the KML file here and have a play about with it in Google Earth.
Last but not least, here are some interesting facts about the flight:
|Max Internal Temperature:||19.6|
|Max External Temperature:||16.3|
|Min Internal Temperature:||-26.8|
|Min External Temperature:||-63.1|
|Max Altitude Recorded:||29958|
|Max Voltage (SP1):||7.67|
|Max Voltage (SP2):||8.96|
|Average Voltage (SP1):||1.88|
|Average Voltage (SP2):||2.51|
|Max Power/mW (SP1):||406.28|
|Max Power/mW (SP2):||419.23|
|Average Power/mW (SP1):||44.58|
|Average Power/mw (SP2):||58.92|
It certainly has been a hectic few days – from the moment, Wednesday afternoon, I obtained permission for the weekend it’s been non stop! I am delighted though that HABE2 was a great success! I will try and write a full rundown of the flight in the next few days, but for now I’ll just give a few quick facts about the launch.
After waking up Saturday morning, I checked the prediction and nothing had really changed, so I gave the launch the go-ahead. The extremely cold conditions slowed down the launch setup due to very cold, numb fingers! In fact, for the last 10mins of setup/launch it started snowing. Despite the slower than usual setup everything was going fine until it came to the last part – the filling of the balloon. We had a faulty adapter! No helium whatsoever was flowing out! This was devastating – with the payload all ready to fly and transmitting it’s location perfectly it was looking like the launch would have to be called off. A quick chat to the other guys on the IRC channel, my fellow HABer/ist (not sure the correct phrasing!) in Worcester, Will Duckworth, came to my rescue after he drove his helium adapter to the launch site! A big big thanks to Will who saved the day! His HAB project is here.
So finally, about 1hr later than planned HABE2 took to the skies! The flight lasted about 2.5hrs and was recovered from a horse field near High Wycombe. At this point I’d like to mention how accurate the predictor is – yet again pinpointing the flight path to within a few km – incredible. The highest reported GPS position was 29, 958m (just 42m shy of the big 30!) – but, if the refresh rate of the GPS and the length of the cord connecting the payload to the chute and onto the balloon is considered I may well have just hit the 30km mark. However – this launch was never intended to go as high as my previous one; I needed a quick ascent and descent (which meant compromising on altitude) due to the predictions.
The camera worked perfectly resulting in some fantastic photos and a couple of short videos! The best can be seen here in my flickr set. See if you can spot the moon and aircraft vapour trails! I’m very pleased with how these turned out.
All the other main components worked great, the SD “black box” style logger has resulted in a significant amount of data being logged – I am now trawling through it all and I hope to have some nice graphics soon(ish). One interesting fact so far – the coldest temperature recorded during the flight was -63.1C!! That makes our -5C temp look strangely warm!
Keep tuned as in the next few days/weeks I’ll be providing a full analysis of the launch and hopefully producing some nice graphics.
For now – I’m very pleased with how it all went considering what could’ve gone wrong. If you have any questions please do drop me a comment below or email me or pop on the IRC #highaltitude
Well – what a frantic few days it has been… I’ll give a brief run through as the payload still need completing!
Wednesday afternoon: I was on the IRC and David Akerman (daveake) posted a link for the prediction for his launch this Saturday. It looked like a good prediction, so I decided to run one from my launch site; no intention at this stage to launch. It turned out to be a great prediction, actually landing in this country (the previous weeks had been landing in France or beyond!). There were two big issues at this point: 1) The payload wasn’t even completed and there were still some nasty bugs present in the code. 2) I didn’t have permission to launch.
After a quick call to the CAA I managed to obtain permission for this weekend (4th/5th Feb) – many thanks to David Miller at the CAA for getting this sorted in such short notice. As of yesterday evening, I now have permission to launch. The next big hurdle was getting the payload completed on time. Despite the huge number of hours I had put in the past 2 weeks, it still wasn’t stable – albeit a rather buggy beta version.
Over the last day and a bit I’ve fixed all the bugs I can see and built most of the payload stuff. Yesterday I ran a full systems check and everything worked apart from the camera – oh no, not this again… (you’ll probably remember that HABE1 was plagued by complete camera failure). This however, wasn’t linked to the HABE1 bug. Initially I thought it was a software issue as I’m running a modified version of CHDK that allows me to switch between photos and video (risky, I know..). However, it appears to be it was actually a failure of the alkaline batteries due to the cold temps outside. This meant I only got around 100 photos (only the 1st 30mins of flight) before the batteries conked out. For the flight I will be using lithiums which have a much better tolerance to cold temperatures thankfully… As I’m writing this the camera is outside with lithiums in running a final check. If it’s all positive then it gets the clearance to fly from me!
Lastly, I’ve just finished soldering all the solar panel logging equip up; I just need to pop the flight board in and solder up all the antennas (not an easy job at all). After – final checks, then time to pack the car for tomorrow.
The current prediction is ok – not great – but ok. I’ll be monitoring this throughout the day and tomorrow morning.
What’s new/updated on HABE2:
- Software rewrite – this has resulted in a fair few bugs as I didn’t test as I was going along (mistake), though it’s resulted in a more efficient and readable software
- Swapped old temperature sensors out for newer high precision ones
- Uplink is present – simply to test range (let me add at this point I’m not expecting great range)
- Camera now takes video as well as photos
- “Black box” present on the flight – SD card logging system should log everything for review after the flight
- Cutdown module – this can be activated via uplink and is automated by the flight computer should the payload stray outside a “safe” area
- Solar panels – 2 high performance small solar panels present; I’ll be logging data using two different loads.
- Launch site: Ombersley, Worcester.
- Estimated time of launch: 11am GMT (setting up around 10am)
- Flight time: approx 2.5hrs
- Check here, twitter (@adamcudworth) or the IRC for the most up to date information regarding the launch. If you would like to come along to the launch please drop me a line either by email or the IRC (#highaltitude and my nickname: cuddykid).
- Track the balloon live during the flight here
- I would really appreciated any help – whether it’s turning up to help out with setup/launch, or helping track by listening in – thanks!
Hopefully the launch will be underway within 24hours! Over and out…
Just a brief update regarding HABE 2:
I have just sent off for permission to launch the balloon from the CAA. I have specified the last weekend in February and the first 2 weekends in March. I have two main doubts currently:
1) Will I complete the payload on time. There is still a LOT to do and none of the code that I have written has been fully tested yet. If a fairly major bug is present in the code then it will require a significant amount of time debugging.
2) Wind conditions – It’s a very windy time of the year and the high altitude winds tend to blow in the wrong direction (west to east) at this time of the year. Hopefully they’ll be fine for given dates *fingers crossed*.
A note on the side; if you haven’t already noticed there is now a brand new page called “Checklist” where you can track my progress. “Check” it out …. (it’s in the toolbar at the top if you can’t find it!).