Balloon Aerial Photo Mapping

Currently here is not happening a lot and I like to explain why. I found out the the laws in Germany currently against me. My small balloon is handled like a big captive balloon. If you have it on a rope you are only allowed to went up for 30 meters what is by far not enough to get a good areal picture. I was told that the is a lot going on and the law might change to my favour soon but no one knows for sure. I could get a special licence to go higher than 30 meters but that costs between 25 – 250€ for one location not for moving around as I planed.

The funny thing is that if I cut the rope and just let the balloon fly wildly in the plan approach  corridor of Frankfurt airport above me it would be ok. For this I would need a cheap camera and some kind of tracking system to recover the pictures.

Another options would be to build a mix of balloon and kite like seen on the Helikite page. Kites are legal for a altitude up to 100 meters.

So far I have not decided what way to go but I sill having a lot of helium I like to put to good use.

UPDATE: Just to show that 30m is not enough a short calculation: From 30m altitude we could make pictures of an area of about 30m*30m = 900m². For a smaller city like Ingelheim with 50km^2 we would need to make over 55000 pictures. Each image has to be fixed on the ground by 4 GPS dots. So this is just impossible!

From 100m altitude we would still need 5000 areal pictures but the 50km^2 are with all the boring fields around the town. Still a lot of work but possible. Anyway, maybe it is clever to just buy the pictures. Digital aerial photos made from a air plane in black and white colours costs 1,6€ per km². So just 80€ for the whole city!

But maybe this is all not necessary because Bayern has already shared there areal photos with OSM in exchange for the manpower to map it. Hopefully others are joining in. I mean, who pay our government to make those pictures?

Still, I am waiting for better weather. Sure there have been some good days but none where I had time for this. Meanwhile my balloon has been waiting patiently in the shelter.

I left him filled with gas as he was, trying to save some of it. Today he was nearly empty so I decided to pack it back to a safer place. The balloon did not only looked very rumpled but also the plastic had formed concretions. I used a very impressive trick I found on the internet (where else!).

With a hair-dryer I headed the balloon up and the plastic morphed back to it’s original form. I should have mad a video because the morphing looked really amazing but you can still see the difference on the pictures.

Since January I am trying to find out if it is legal to launch a ballon in the way I want. The German law says it is allowed for kites up to 100 meters but with captive balloons on a fixed rope only up to 30 meters. I think my small balloon is more like a kite but unforgently no one wants to approve that. I wrote to the DFS “Deutsche Flugsicherung” who are responsible for whole Germany. The DFS forwarded me to mwvlw.rlp.de because I am in Rheinland-Pfalz but those send me back to DFS. So I wrote DFS again and explained they created a loop.

Now after 2,5 month I got an anwser. Guess what? They are writing that they are really not responsible.

Even if that is true, why did they need 2,5 month to find that out…

Yesterday the sun was shining and I used the Sunday for a new round of my experiment. Since I still don’t know what caused the explosion the last time, I was very careful during the filling. Unfortunately I only had a pink balloon left so it is a bit girly but who cares.

The balloon turned out to be more stable than the last one. Soon it hovered over the drill I used as anchor like last time. The camera box got mounted with some plastic robe under the balloon. I filled the balloon till it carried the camera and some stones. The stones provided some extra weight for the robe which the balloon had the carry later. I sealed the balloon clip from the kitchen and secured it with a knot.

On the first flight I didn’t want to use my camera so I put in some stones to replace the camera. This turned out to be a good idea because the wind was stronger than I expected.

At first the balloon lifted up very well. As it got high enough the wind was starting to push the balloon around. That was a problem because in my garden are many high trees and a house, of course. It looked a bit like a kite. Once the robe got stuck on the roof but luckily I got it free somehow. Still the wind was always pressing the balloon back to the ground. Once just a few centimetres over our pond. I was really happy that I used stones instead of the camera on the first flight.

Back in the hanger I redesigned the mounting and put in the camera. But oh no! The balloon wasn’t carrying the camera any more. The clip wasn’t holding properly and I had lost a lot of gas.

After refilling it was getting serious. I programmed the camera to start making pictures after 10 minutes in a 15 seconds period. So I had enough time to run down the street to a place with more space for manoeuvring. As I got there the camera got bored and turned off (Stupid power save). Since the camera was well secured I could not reach the power switch, so I had to untie the hole box. I should make a hole for the switch.

With the camera powered on I made a lot of pictures of my feet while I tied the box back to the balloon. But finally everything was flying but still not as high as I need to. I am guessing I got 10 meters so all the pictures showing beside my feet only bricks from different distances and altitudes. Not so amazing but still a good step forward. I was still leaking gas. So I need to fix this and I need more upwards lift. Maybe I use two balloons next time.

One thing is for sure: You get a lot attention if you running around with a gigantic balloon. It is perfect promotion!

I was guest in the Fnordfunk Radio of the Choas Computer Club Mainz. We talked about OpenStreetMaps and my balloon project. If you understand german you might want to listen to the podcast.

The good news first: The web page is online (as you see) and I did the first attempt to launch a balloon.

I finished the light width polystyrene case for the camera and started to fill one of my big balloons. Fully blown up it’s 2m long and 40cm thick, so it’s really a big thing. I bought a big 20L helium cylinder a few days ago and attached the balloon with some rope to get the helium in without losing any (picture on the way).

For security reasons I did the filling in a greenhouse so the balloon can’t float away while I am trying to tie my camera on it. I filled slowly and after the balloon was filled half it begins to hover but my cordless drill could hold it on the ground easily.

When the balloon was nearly full I saw a irregularity on the balloons hull but I didn’t look too bad. I wasn’t sure how much helium was already in there when the hole thing just exploded with a loud BANG!

But surprisingly I didn’t felt depressed. Ok, I lost a 2,25€ balloon and ~4€ helium but at least it happend on the ground and not in 100 meter hight with my camera attached. Maybe I should think about a parachute…