Beyond 62

I have looked at many similar projects online and one of the things I noticed was that the payload and therefore the camera is tilted vertically and sideways most of the time.

From Alexei Karpenko’s Flight 2.

This payload is pushed by the wind, which is more or less strong depending on the altitude. The Jet Stream for example usually blows from 20,000 to 50,000 feet AGL (About 6,000 – 9,000 meters). At max altitude, the air pressure has dropped so much that I don’t believe there is much wind. Am I wrong?
The payload movements come from its balance, which is usually mediocre.

The good thing about it is that you can get good pictures at different angles (straight down or straight up) and get very valuable information on how the flight went. But that’s only a couple of pictures out of hundreds.

Most people have built it with a regular foam insulated box hanging from a balloon.  I don’t think it’s the way to go. To take great shots, I need to keep the camera stable. The camera’s EIS Stabilizer will help, but I can’t just rely only on it.

Now How can I get the camera from moving too much?

This is where Aerial Photography shows its nose. Pierre Picavet invented a greatly used suspension system called after him Picavet. The Picavet suspension or Picavet cross provides a stable, self-leveling platform that resists twisting and swinging movement of a kite/balloon line.

Picavet Suspension Principle

Then for a balloon, I would need a spacer to control the level of the payload.

I don’t think I necessarily need the Picavet cross. I can attach it to the payload directly such as:

Each part must have a specific size for the stabilization system to work at best. It’s pretty easy to build or cheap to buy. You can find some simple kits here and there.

Now my only concern is … once the balloon explodes.

What will happen during the descent?

Have you see all those lines? The payload’s weight will drive the whole system down (picavet, spacer, radar reflector and parachute). I am afraid that this becomes a giant shitty mess during the way down, tangling the parachute and making it  crash at full speed.

I think it’s worth the shot and that a problem with it should be easily identifiable during the tests.

What do you guys think?

Picture from Flight 2

I looked over and over again at some of the products that I saw online. None were meeting my needs.
So this is how I made my decision:

Need: I need a GPS tracker to retrieve the Payload

Optional Bonus: Working above 60K ft ASL would allow me to:

• Follow it in real time
• Record the Flight Path and Max Altitude Reached

Facts:

What if the payload lands in a zone without signal coverage?

• I cannot trust GSM.

Why using GSM in the first place?

• Because it’s way cheaper than any other technology.

Does it work above 60K ASL?

• The GSM transmissions won’t work above a couple of miles high but it doesn’t mean that the GPS of the phone will stop working.
  (Additionally It’s illegal to operate a cell phone in the air)

Will the phone be able to record the flight path and altitude?

• That’s the great unknown. Some people claim it did.
  I am skeptical but have no other solution.

What if the phone dies (bug, cold, battery, hard landing, …)?

• I want a backup system that doesn’t use GSM.

Why not using only the backup system then?

• Because it’s the most critical feature of the payload. For my first flight, I must have a backup tracking solution.

Will the backup system work above 60K ASL?

• Ideally yes, but I haven’t found one able to do it so far.
  It only needs to work once the payload has landed.

Conclusion:

I need two autonomous and independent tracking systems. Each system must have its own power source, GPS and a different communication technology.

Primary system: GPS Phone + Battery Charger + External Antenna (optional)

Backup system: SPOT personal tracker + Track Progress

Details:

An Apple Iphone/Google Nexus One would be a first but they don’t meet the environmental requirements. The GPS Phone can be any GPS Phone that can be powered by lithium batteries. Most people have used the Motorola i290. Activated with Max Cache Size, it seems possible to record the whole flight path.

I will use the SPOT personal tracker for 4 reasons:

1. It uses Globalstar’s communication satellites, it’s not limited by cellular coverage;
2. It works under tough operative conditions (-45C, shockproof, waterproof, floating)
3. It uses lithium batteries
4. I can personally reuse this device for my next adventure.

Both devices should be trackable online through instamapper and spotadventures.

Total Cost: $300

Next: The Camera and Stabilization System!

When I found GPSFlight’s tracking system, I thought that it was it. They provide a complete solution with a GPS Integrated Wireless Transmitter, a USB Base Station Receiver and a Telemetry Software. They include even cooler features like an accelerometer and a temperatures probe.  But most of all they sell a complete turn key solution, hardware and software, working above 60.000ft ASL at rates up to 4 Hz.

I really like their ST900e Transmitter .  I contacted them and each piece or hardware comes in different versions: 100mW, or 1000mW with and without additional options. It seems that 1000mW would provide a safer range than the basic option. But what’s the max distance for a 1W transmitter and 1W receiver? It’s not clear yet. I think that I need a 30 to 40 mile line of sight range. This distance seems reasonable. A better understanding of the performance would be essential.

The cost?  Transmitter+Receiver+Software:

$1430 for 1W

$985 for 100mW

I can’t decide if it’s crazy expensive or a bargain compared to the time that I would need to achieve this on my own. Part of it is because I’d choose the advanced transmitter. The features look really really cool and give me ideas beyond MSP-1/2.

Sounds Great, right?

It is, except that I have an major unexpected money outflow coming soon. The bad news came this week and it makes me rethink my entire strategy. By looking on the market, I found great tools and ideas but I have to keep in mind the goal of MSP-1:  Launch asap a balloon to near space, get it back safely and learn as much as I can from this first experience. BIG WINS!

So even though I kind of hate it, I need to go with the GSM solution that is 10 times cheaper and inaccurate.  Plenty of people made it that way. It also means that I probably won’t have a record of the max altitude reached. I am back at square one but failure’s not an option.

Designing a space balloon is not such a simple thing. Ideally I would like a simple, cheap and reusable system.
Using off the shelf components and subsystems is by far the easiest and fastest way to build it. But like everything, you don’t necessarily have it for a good price, with all the cool features and options.

I spent some time studying what would the payload need this weekend and I ended up with more questions than answers.

Where The Hell is My Balloon?!

The top priority is to retrieve the payload after its launch. To do so, I need to :

1. Log the balloon location (latitude, longitude, altitude)
2. Send this information to the recovery team on the ground on a regular basis

Problem#1: Location

The best way to track the balloon is to use a GPS. But most GPS receivers seem to have hard limits at  60,000 feet ASL (18km). DoD regulations prohibit standard consumer GPS receivers from functioning above 60,000 feet and 999mph. It would be considered as a ballistic missile.

I would like to reach 100.000 ft ASL so I need to find a GPS that work above that threshold. Multiple lists of GPS working above 60K ASL are available on Internet and specialized forums. However almost all of them are single devices that need to be integrated with electronic boards. Yes you can tell that I really don’t know anything about all this…

But what does that mean Not Working Above 60K ft?

Does that mean that the GPS literally stops functioning? Or does that mean that it just doesn’t calculate the altitude? A potential workaround would be to use a barometric altimeter but it tends to not be accurate at high altitude. How inaccurate are we talking about? 1000 ft or 10.0000 ft ? Am I wrong or is the formula just more complex at high altitude?

So basically,

• I need to find a GPS working above 60.000 ft ASL
• I need to find a way to determine the max altitude reached

Problem#2: Communication

GSM can work up to 10 miles high  for old phones (about 50.000 ft), newer phones work about up to about 6 miles (31.000 ft). So tracking a balloon using GSM communications implies losing contact during the ascent and hopefully getting it back during the descent. The main consequence is that the recovery team may end up very far from the balloon or worse, lose contact and never find the payload.

I tried to deny it and find another solution but apparently the only way to track the balloon during the whole flight is using ham radio (amateur radio). A radio transceiver needs be connected with the GPS to send the location on a regular basis to a receiver on the ground. Unfortunately I haven’t found any out of the box solution yet and I don’t know enough about ham radio and electronics to build it myself.

So it all comes down to compromises:

• Either spending some time building my own tracking system
  Pros: It will do what I want and it’s not very expensive
  Cons: It will take forever to build it and test it

• Either using a GSM phone but risking losing the payload
  Pros: It’s super easy to put in place and is the cheapest solution
  Cons: The payload may land 250 miles away from us or we may never find it

• Or finding the appropriate turnkey solution
  Pros: It will do exactly what I am looking for
  Cons: Usually very expensive

So I have a couple of options that I need to study in greater details. I just wanted to give you a brief overview of my main questions.

Welcome to Beyond 62!

I am officially starting this project and I am really excited to write this first blog post. I will refer to this project as MSP and this is MSP-1.

During the next couple of weeks, I will share with you my questions and problems, the solutions I found and my progress to send a balloon above 100.000ft. After doing some preliminary researches, I found out that most people have 2 ways to do it.

1. Either use as many out of the box devices as possible
2. Either build everything themselves

Despite many hours spent studying electronics in college, I can say that I pretty much know nothing about it.
Building a custom system such as a GPS connected to a circuit board with a temperature and pressure sensor seems out my league for now.

I want to go simple. I want big wins with the least efforts. I may have to approximate the altitude reached for example but if that saves me hours and hundred of dollars, well for my first trial, so be it. I didn’t set a deadline or any time frame yet but I expect MSP-1 to be launched by the end of January.

If you have some questions about all this, I suggest that you check here. Otherwise feel free to leave a comment or to contact me.