How to deploy parachute after balloon pops

[XxZHALO13Xx]

Hello, not sure if this is the correct forum to post this under, but anyway. I am planning on sending a gopro around 100,000 feet up. When the balloon pops, I want it to eventually open a parachute and fall down to the ground safely. Although if the parachute opens right away, it could drift miles away from the launch site. What would be the best way to make the parachute open? Thanks for your help

 

[CWatters]

Google altitude sensor? There are boards like this available...

http://www.maplin.co.uk/p/adafruit-bmp180-barometric-pressuretempaltitude-sensor-5v-ready-n55dq?gclid=CjwKEAiAuKy1BRCY5bTuvPeopXcSJAAq4OVsG91LU1QPef6LFA4hiLMJf27BB5uDyEzHKnrLED-t-RoCBXHw_wcB

Would need a micro and perhaps a servo as used on model aircraft to release the parachute.

 

[CWatters]

Read this...

http://www.thefintels.com/aer/hab.htm

Has some comments on parachute size.

 

[gatopardos]

You could put a gas sensor inside the balloon and fill it with the particular gas i.e. hydrogen, or draw a strip of conductive paint on the balloon.

 

[mrspeedybob]

How about a simple mechanical switch held open (or closed) by a weight. When the balloon pops the camera will be in free fall (weightless).

 

[berkeman]

Hello, not sure if this is the correct forum to post this under, but anyway. I am planning on sending a gopro around 100,000 feet up. When the balloon pops, I want it to eventually open a parachute and fall down to the ground safely. Although if the parachute opens right away, it could drift miles away from the launch site. What would be the best way to make the parachute open? Thanks for your help

If it were me, I'd use a microcontroller with a GPS module and a steerable parachute to guide the vehicle back to the launch point. Why have to drive around looking for your payload? The balloon is going to drift a lot on its own, so using a steerable parachute to glide back to the launch point only makes sense, IMO...

 

[Daz]

Since when did PF encourage dangerous activities?

To the OP: don’t even consider doing what you describe until you have obtained approval and authorization from the relevant regulatory authority. In the US that would be the FAA, in the UK it would be the CAA.

Since your aerial vehicle (balloon) will be operating out of line-of-sight it will, of course, be required to carry the relevant PSR reflectors and probably anti-collision lights, too. And in most parts of the world, everything above 10,000 feet is designated category C airspace. If you’re planning to fly your vehicle in cat. C airspace, then in most countries it will be required by law to carry a mode-C transponder. And to operate the mode-C you’ll need a GPS and a barometric altimeter.

If you ignore the rules and your GoPro ends up in the engine of a commercial airliner at 38,000 feet, you’ll need a spare thirty million or so lying around to pay compensation. And if it smashes through the cockpit of an airliner flying at 500MPH, killing hundreds of people, then I wouldn’t rate your chances of avoiding prison very highly.

In short, don’t fly anything above 10,000 feet unless you know the legal and regulatory landscape. Even below 10,000 feet you can still get into trouble. For example, did you know that if your balloon passes within a 30 mile radius of a primary airport in category-B airspace you’d also be committing a criminal offense?(At least in Europe, probably the same in the US.)

 

[berkeman]

To the OP: don’t even consider doing what you describe until you have obtained approval and authorization from the relevant regulatory authority. In the US that would be the FAA, in the UK it would be the CAA.

Good point. We've had threads here before about amateur high-altitude balloon flights, but I don't remember offhand what approvals are needed. Thanks for bringing up this aspect.

 

[CWatters]

Do check with the FAA but the link I posted above says...

http://www.thefintels.com/aer/hab.htm

If you keep you balloon/payload within the FAA exempt specs, such as payload under 6 pounds, payload under the density limit, 50 pound break force on the payload line, etc. The flight is FAA exempt and you don't need a back up cut down system, radar reflector, FAA waiver, etc. You can just fly the darn thing!

 

[CWatters]

You could put a gas sensor inside the balloon and fill it with the particular gas i.e. hydrogen, or draw a strip of conductive paint on the balloon.

How about a simple mechanical switch held open (or closed) by a weight. When the balloon pops the camera will be in free fall (weightless).

Ok so both of these suggestion will tell the on board electronics that the balloon has popped but then what? The OP doesn't want to deploy the parachute immediately because it will drift a long way.

You can't safely use a timer to delay the opening. What happens if the balloon bursts at 50,000 ft instead of 100,000 ft ? The time delay might still be running when it smashes into the ground.

 

[mrspeedybob]

...The OP doesn't want to deploy the parachute immediately because it will drift a long way.

Maybe.
A longer decent would mean more photos or video gets taken. That would mean more options available for whatever he's using it for. Having several times more raw material to work with may be worth a longer retrieval drive.

 

[CWatters]

He seems quite clear in his OP.

 

[XxZHALO13Xx]

Thanks to all who commented. I do know I will need to contact the FAA for this. But also, where I live there are roads and woods. I like what @berkeman said about being able to control the parachute. This would be very very useful. I'm not quite sure how to go about doing this though. If you can, could you send me a pm and help me figure it out? Thanks

 

[A.T.]

I like what @berkeman said about being able to control the parachute.

I doubt a "steerable parachute" will make it all the way upwind, back to the lunch side, so you have to drive for miles anyway. Unless you plan to do this many times, the time you will spend on building and testing the steering will be more than the potential time saving during retrieval.

 

[XxZHALO13Xx]

@A.T. That's also a good point. What's the farthest distance it could travel?

 

[CWatters]

That depends on how fast it goes up and the wind speeds. Flights of >50 miles are possible...

 

[XxZHALO13Xx]

That depends on how fast it goes up and the wind speeds. Flights of >50 miles are possible...

Thanks, also. Can anyone help me out with a tracking device? What is a good way to be able to locate it after it lands?

 

[Nick tringali]

Go-pros are light, I'm not a physicist but it will probably blow around with the parachute a lot. I suggest gps

 

[berkeman]

Thanks, also. Can anyone help me out with a tracking device? What is a good way to be able to locate it after it lands?

What has your reading indicated would be a good tracking mechanism? What research have you been doing on your own outside of asking questions in web forums?

 

[mrspeedybob]

Why a GoPro?

You can get a no-contract cell phone fairly cheap.
Put an app on it that will take pics or video and save to a cloud service over the cell phone network.
Put another app on it that will allow you to track it remotely.

Send it up with a balloon and parachute system. When it comes down, log on and see where it landed. If it winds up in the top of a tree or someplace inaccessible, you can still get the pics/video from the cloud service.

No pun intended on the "cloud" thing ;-)

 

[Nick tringali]

Why a GoPro?

You can get a no-contract cell phone fairly cheap.
Put an app on it that will take pics or video and save to a cloud service over the cell phone network.
Put another app on it that will allow you to track it remotely.

Send it up with a balloon and parachute system. When it comes down, log on and see where it landed. If it winds up in the top of a tree or someplace inaccessible, you can still get the pics/video from the cloud service.

No pun intended on the "cloud" thing ;-)

Those cell phones will not capture a fraction of the image a go-pro will, if he is sending a big balloon up in the sky he might as well go the extra mile and buy a go-pro, I would hate to be him if he gets a hold of the video and it is garbage.
Even the Iphones wouldn't do the trick in this situation, a go-pro is necessary.

 

[anorlunda]

Based on the video below, I conclude that a Gopro can be dropped from nearly any height without a parachute and survive (maybe). At least the chance of survival won't increase much with a parachute.

That still leaves you with the tracking problem, but you can forget the parachute and simplify your project.

P.s. Be sure to watch the video to the end, it will make you smile.

 

[A.T.]

I conclude that a Gopro can be dropped from nearly any height without a parachute and survive

The question is if you would like to get that falling camera on your head or car.

 

[anorlunda]

The question is if you would like to get that falling camera on your head or car.

A very good point, but a small parachute might not mitigate that risk very much.

 

[XxZHALO13Xx]

A very good point, but a small parachute might not mitigate that risk very much.

Right, which is why I think a parachute would be needed. I plan on putting it inside a Styrofoam container with a cut out for the lens of the gopro. I also want to include the GPS system which it seems like a phone would do. And a battery pack to power it all to make sure it lasts. Out of the box, I want to have a small parachute that will slow the fall but not completely blow it far away; also the weather balloon to carry it up there. I found this link helpful http://space.1337arts.com/hardware/comment-page-10#comments My question is how to slow the fall while not majorly changing how far it lands

 

[mrspeedybob]

You could use a collapsible Rogallo style wing, like an old 60's era hang glider, instead of a parachute. Spring load it to open when a solenoid activates or something like that. The advantage here is it has a frame and a direction of flight. if the prevailing winds at your launch site are west to east, for example, you can magnetize the cross bars so that the right side wants to point north, and the wing will want to fly west, into the wind.

 

[XxZHALO13Xx]

You could use a collapsible Rogallo style wing, like an old 60's era hang glider, instead of a parachute. Spring load it to open when a solenoid activates or something like that. The advantage here is it has a frame and a direction of flight. if the prevailing winds at your launch site are west to east, for example, you can magnetize the cross bars so that the right side wants to point north, and the wing will want to fly west, into the wind.

That sounds cool, although it seems a little hard to set. What about making a parachute deploy about 500ft up? Would that be enough time to slow it down?

 

[CWatters]

There is a lot on that link I posted earlier..
http://www.thefintels.com/aer/hab.htm

Including info on..

Why he thinks larger parachutes are better.
GPS solutions that don't rely on the phone network

 

[Nuke]

Use a paper streamer (ribbon) to slow the descent and help find you capsule. Much simpler. Use air resistance to unfurl it.

 

[XxZHALO13Xx]

Use a paper streamer (ribbon) to slow the descent and help find you capsule. Much simpler. Use air resistance to unfurl it.

That's a great idea! I never thought of that, thanks! Now, to deploy it, should I put it inside the balloon coiled up? When the balloon pops it would deploy.