In July 2014, I blogged about our mission to send a Superman Action Figure to the edge of Space and back for Mattel toys. - Hack Superman Blog The project was to recreate the record breaking freefall from 39km high by Felix Baumgartner in the Red Bull Stratus capsule. This record has subsequently been broken in late September 2014 by Alan Eustace, who travelled and jumped to from just over 41 km.
After a couple of planning sessions, the team went away to work on their tasks. Then in early September, we all got together for a long weekend at RLab to bring it all together and prepare for launch.
Here's the video of the launch!
Now for the behind the scenes account...
Below is the finished capsule and the key components.
The launch vehicle to send Superman and his capsule up to the Stratosphere was a Weather Balloon filled with Hydrogen gas. We chose to launch in Ross on Wye near Wales in the UK, as this was an ideal location that was well away from large cities and frequent air traffic. The British weather is some what unpredicatable!, so a summer launch window gave us more opportunities for a successful mission. The actual launch site was in a field ajacent to Dave Akerman, one of our team members, back garden. Dave is a High Altitude Balloonist and Radio Ham, and has scores of launches under his belt, so we were in good hands.
After applying for permission to launch from Air Traffic Control, we monitored the weather conditions via weather predictor software the few days leading up to our launch window. The weather patterns were predicting low winds and warm and dry conditions, so this was perfect, and also meant that Superman shouldn't drift too far from the landing site.
The software allowed us to monitor where the capsule and Superman were likely to land. The "habhub" website has some amazing tools that can predict where your payloads are likely to land based on the weather conditions, the weight of the payload and the size of balloon and parachute used. The predictors allowed us to adjust the payload weight, balloon and parachute size and then calculate the approximate height that the balloon will burst and the rate of descent. If the Superman or his capsule were looking like they were going to land in a city, near a motorway or in dense forest, we could change the balloon size or the amount of gas used, add or reduce the payload weight or have a bigger or smaller parachute.
When we were ready for lift off, we walked the capsule out to the open field. The capsule was connected to the balloon via a 10 metre nylon cord. Halfway between this was the parachute. The balloon was putting up quite a struggle! When inflated it as big as a small car and strong enough to lift a child off the ground. We let it go and watched it climb.
Both Superman and Felix travelled up to the Stratosphere. It took about 1 hour 40 mins for Superman to travel to his jump altitude of 29 km. Although this is not technically in Space, which starts around 100 km high, Weather Balloons burst in the amoshphere before they can get anywhere near the height you need to get into orbit. However, as you can see, the views from the stratosphere are stunning!
We decided to eject Superman at a height of 29 km. This was lower than Felix's jump altitude of 39 km. The Weather Balloon we used to carry the capsule was predicted to burst at over 30 km high, so we wanted to ensure Superman had left the capsule before the balloon carrying the capsule burst. The capsule continued to climb upto 34 km, where it burst. (see ballon fragments circled below)
The ejection mechanism was relitively low tech. We did experiment with a 3D printed mechanism, but we didn't have time to properly test it, so we substituted it with a piece of sponge.
In total we had 5 trackers. The main trackers were on Superman and in the capsule. We had 3 back up trackers in the capsule, 2 of which were powered by Raspberry Pi 's and were also taking pictures and sending them back to the ground. We used additional trackers to ensure we could find the capsule, although the trackers we designed worked perfectly! The radio modules we used were on the 433 mhz band. We used radio receivers tuned to the frequencies of the trackers on Superman and his capsule. We named the trackers after Superman related things, the tracker inside Superman was named "Kal-EL", the name in given to him by his parents on his home planet of Krypton.
The trackers regularly sent back their GPS position, and we were then able to position them on a map. When Superman jumped out, we got into our cars and continued to follow his signal. We then drove in the direction he was falling.
It took around 50 mins for Superman to fall to the ground. When we were close to the landing site, we had to continue on foot. In the picure above you can see us with hand held radio receivers and YAGI Antenna to pick up the signal transmitting from the trackers. We put the recived GPS co-ordinates onto a map on a tablet computer and went off in the direction to where they had landed.
It took Superman about 2.5 hours to travel up and back to the ground. Superman and his capsule landed less than 20 km away from the Launch Site. The wind speed was about 10 km per hour max, so they didn’t drift too far. If we had launched in the winter, Superman could have caught the Jet Stream and drifted and landed somewhere in Northern Europe.
We found the capsule first. It had landed at the end of Hope Lane. Coincidently, “Hope” is the meaning of Superman's “S” symbol to the Kryptonians (Superman’s home planet)... cue the Twilight Zone music...
Superman however landed in a very tall tree in the middle of a field full of Sheep! Ironically, it was the tallest tree within quite a few square acres!... What are this odds of that happening!...Anyway, we broke out the climbing gear and in the true Superman spirit of rescuing a cat from a tree, we reclaimed him.
How to build your own
So that anyone can recreate our mission, we have shared the project notes, including the open source PCB design files for the tracking units and the 3D printed components that we created in our DesignSpark tools. You can find these in our DesignSpark DesignShare Section under, Hack Superman - High Altitude Tracker. Jude Pulllen had also created an Instructable project, with details of how to create the Correx Capsule that carried Superman.
3D print your pieces with 3D printers from RS Components
Finally, I'd like to thank...
Dave Akerman - High Altitude Balloonist and Radio Ham for enabling us to do this.
Jude Pullen - Modelling Guru who helped us create an awesome capsule
R-Lab - with special thanks to Richard Ibbotson, Alex Gibson, David Price who designed the PCB's and 3D printed components.
Newbury Electonics - with thanks to Philip King for kindly donating the PCB's that we used inside Superman.