Solar balloon free flight contest

catman529 · Nov 01, 2007, 12:14 PM

I guess this is the right place to post this. I am running a contest on my solar balloon Web site this fall. If anybody might be interested, check it out. any questions about making or releasing balloons, just PM or email me.

http://www.solar-balloons.com/fallcontest.html

peter_ashland · Nov 02, 2007, 09:57 AM

Does anyone do RC control of these balloons? It would seem that you could rig a top valve and some ballast weights on a receiver and do more than tether and free flight.

BTW: Cool site. You need to add glitter tape to the kits so the UFO nuts go nuttier.

http://www.rense.com/general51/myst.htm

catman529 · Nov 02, 2007, 10:04 AM

I have been meaning to finish a UFO-shaped balloon. some silver mylar will add some metallic shine....

as for RC solar balloons - I have had the same kind of ideas, but no gear. What would be cool is a simple 2 or 3 channel setup - ducted fan at mouth to pump air into the balloon, servo to operate a top valve, and maybe anothe one to operate rotation vents on the sides of the balloon (this would be good for AP, so you could get panoramas, etc). maybe someday I will try this out. they do make RC hot air balloon models, which are like conventional hot air balloons and heated with propane.

oh yeah- I'm just getting ready to make a balloon for release right now... (not for the contest though, just to try to beat my own records)

peter_ashland · Nov 02, 2007, 10:28 AM

Gonna be hard to beat that 230 mile record.

I don't think you would need a fan. Just ballast and a top valve. A cheap full range receiver, 2 servos, and a lipo.

You can rig some of the cheap servos to move directionally instead of positionally. Put the weights on a screw mechanism and drop them off like a candy bar from a vending machine. The top valve could be fishing line driven from a spool on a servo.

catman529 · Nov 02, 2007, 03:31 PM

But with ballast, once you run out, you can't stop a fast descent anymore. It would be cheaper though. And the weight should be sand or something, cuz you don't want anything to go through a windsheild or something.

Oh yeah, you wouldn't need a spool of line, just enough length to fit. There are vents that open when you pull just a bit on them.

JWilliams2 · Nov 02, 2007, 04:23 PM

This is a cool idea (solar balloons).

peter_ashland · Nov 02, 2007, 07:42 PM

Quote:

Originally Posted by catman529

But with ballast, once you run out, you can't stop a fast descent anymore. It would be cheaper though. And the weight should be sand or something, cuz you don't want anything to go through a windsheild or something.

I know they use ballast on the He balloons. But they also can dump more He in to get more lift as well. I was thinking little sandbags of an ounce or 2 each. A half a pounds worth would give you 8 shots at changing altitude. It is really just to correct for dumping to much air out the top.

Quote:

Originally Posted by catman529

Oh yeah, you wouldn't need a spool of line, just enough length to fit. There are vents that open when you pull just a bit on them.

I was thinking you would probably need to wind the line more than an inch a servo is going to allow to get any valve at the top to open.

Can you point me to any of these valves?

peter_ashland · Nov 02, 2007, 08:05 PM

Quote:

Originally Posted by peter_ashland

Can you point me to any of these valves?

http://fireflyballoons.net/valve.html

I don't think a parachute valve will work on a balloon this size. Not enough air pressure to seal it. Have to look into a side panel vent.

catman529 · Nov 02, 2007, 08:48 PM

Quote:

Originally Posted by peter_ashland

http://fireflyballoons.net/valve.html

I don't think a parachute valve will work on a balloon this size. Not enough air pressure to seal it. Have to look into a side panel vent.

parachute vents on balloons of this size (5-10' tall) need to be sealed with small strips of velcro to stay shut. Look at how rotation vents work though, these will work even on a small balloon with no velcro. The same technique could be used for a top vent, only it would be circular rather than rectangular. I wouldn't use this on any balloon smaller than 7' tall.

peter_ashland · Nov 03, 2007, 08:37 AM

Quote:

Originally Posted by catman529

parachute vents on balloons of this size (5-10' tall) need to be sealed with small strips of velcro to stay shut. Look at how rotation vents work though, these will work even on a small balloon with no velcro. The same technique could be used for a top vent, only it would be circular rather than rectangular. I wouldn't use this on any balloon smaller than 7' tall.

I will keep my eyes out for it. Do you have any links to the design of these? I think the size of the balloon will have to be calculated based on the weight of the gear. But given most of the RC stuff can be pretty light a RC solar balloon should be doable.

catman529 · Nov 04, 2007, 10:41 AM

I have a page w/ instructions for a 7' tall balloon on my site. goto the homepage and click on the "make your own" link in the top menu. I could sketch a simple vent design on mspaint if you want.

peter_ashland · Nov 05, 2007, 03:36 PM

Quote:

Originally Posted by catman529

I have a page w/ instructions for a 7' tall balloon on my site. goto the homepage and click on the "make your own" link in the top menu. I could sketch a simple vent design on mspaint if you want.

Already got 1 made thanks to your instructions.

I assembled it on my wall. The neat part was since the wall was smooth I was able to assemble and cut without much taping in place. It just stuck up there by static and vacuum until the final assembly.

And of course the ceiling fan makes a nifty hanger for it. Just don't turn it on.

So what would a vent look like?

catman529 · Nov 06, 2007, 07:09 PM

balloon looks good - sticking it to the wall is a great idea! Can't wait to see it in flight. I'll try to draw up a vent sketch, it's kind of hard to draw.

catman529 · Nov 06, 2007, 07:23 PM

here's a drawing I just made...hope it makes some sense. I made the balloon sort of see-thru, with the outside being cyan and the balloon being gray. on the inside diagram, the vent is pulled open by the cord so you can "see out". the outside view just shows what the closed vent would look like.

basically, the vent is just an overlapping panel that is not sealed on one end on the inside, so it can be pulled open. when the cord is released, it automatically closes.

peter_ashland · Nov 06, 2007, 07:58 PM

Thanks, I see now how that works.

I will make a few variants of that. The key thing I was missing was the strings in that scalloped vent area. It will insure that the flap doesn't get sucked into it.

I suppose that I can make those from tape.

I am a little worried that the pull on the panel may cause the balloon to collapse and either have the vent not release air or worse not close well. But I suppose the right amount of tape or even an inflated tube of air.

Nov 01, 2007, 12:14 PM	#1
catman529 CPR (Crash, Pickup, Repair) Join Date: Feb 2007 Location: Tennessee Posts: 907	Solar balloon free flight contest I guess this is the right place to post this. I am running a contest on my solar balloon Web site this fall. If anybody might be interested, check it out. any questions about making or releasing balloons, just PM or email me. http://www.solar-balloons.com/fallcontest.html

Nov 06, 2007, 07:23 PM	#14
catman529 CPR (Crash, Pickup, Repair) Join Date: Feb 2007 Location: Tennessee Posts: 907	here's a drawing I just made...hope it makes some sense. I made the balloon sort of see-thru, with the outside being cyan and the balloon being gray. on the inside diagram, the vent is pulled open by the cord so you can "see out". the outside view just shows what the closed vent would look like. basically, the vent is just an overlapping panel that is not sealed on one end on the inside, so it can be pulled open. when the cord is released, it automatically closes. Attached Thumbnails vent is sealed on all sides except the side which the cord is attached to (cord shown in blue) 16.3 KB · Views: 55

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Nov 02, 2007, 09:57 AM	#2
peter_ashland Registered User Join Date: Jul 2006 Location: Grafton MA Posts: 89	Does anyone do RC control of these balloons? It would seem that you could rig a top valve and some ballast weights on a receiver and do more than tether and free flight. BTW: Cool site. You need to add glitter tape to the kits so the UFO nuts go nuttier. http://www.rense.com/general51/myst.htm

Nov 02, 2007, 10:04 AM	#3
catman529 CPR (Crash, Pickup, Repair) Join Date: Feb 2007 Location: Tennessee Posts: 907	I have been meaning to finish a UFO-shaped balloon. some silver mylar will add some metallic shine.... as for RC solar balloons - I have had the same kind of ideas, but no gear. What would be cool is a simple 2 or 3 channel setup - ducted fan at mouth to pump air into the balloon, servo to operate a top valve, and maybe anothe one to operate rotation vents on the sides of the balloon (this would be good for AP, so you could get panoramas, etc). maybe someday I will try this out. they do make RC hot air balloon models, which are like conventional hot air balloons and heated with propane. oh yeah- I'm just getting ready to make a balloon for release right now... (not for the contest though, just to try to beat my own records)

Nov 02, 2007, 10:28 AM	#4
peter_ashland Registered User Join Date: Jul 2006 Location: Grafton MA Posts: 89	Gonna be hard to beat that 230 mile record. I don't think you would need a fan. Just ballast and a top valve. A cheap full range receiver, 2 servos, and a lipo. You can rig some of the cheap servos to move directionally instead of positionally. Put the weights on a screw mechanism and drop them off like a candy bar from a vending machine. The top valve could be fishing line driven from a spool on a servo.

Nov 02, 2007, 03:31 PM	#5
catman529 CPR (Crash, Pickup, Repair) Join Date: Feb 2007 Location: Tennessee Posts: 907	But with ballast, once you run out, you can't stop a fast descent anymore. It would be cheaper though. And the weight should be sand or something, cuz you don't want anything to go through a windsheild or something. Oh yeah, you wouldn't need a spool of line, just enough length to fit. There are vents that open when you pull just a bit on them.

Nov 02, 2007, 04:23 PM	#6
JWilliams2 Registered User Join Date: Jan 2007 Location: NY State Posts: 2,822	This is a cool idea (solar balloons).

Nov 04, 2007, 10:41 AM	#11
catman529 CPR (Crash, Pickup, Repair) Join Date: Feb 2007 Location: Tennessee Posts: 907	I have a page w/ instructions for a 7' tall balloon on my site. goto the homepage and click on the "make your own" link in the top menu. I could sketch a simple vent design on mspaint if you want.

Nov 06, 2007, 07:09 PM	#13
catman529 CPR (Crash, Pickup, Repair) Join Date: Feb 2007 Location: Tennessee Posts: 907	balloon looks good - sticking it to the wall is a great idea! Can't wait to see it in flight. I'll try to draw up a vent sketch, it's kind of hard to draw.

Nov 06, 2007, 07:58 PM	#15
peter_ashland Registered User Join Date: Jul 2006 Location: Grafton MA Posts: 89	Thanks, I see now how that works. I will make a few variants of that. The key thing I was missing was the strings in that scalloped vent area. It will insure that the flap doesn't get sucked into it. I suppose that I can make those from tape. I am a little worried that the pull on the panel may cause the balloon to collapse and either have the vent not release air or worse not close well. But I suppose the right amount of tape or even an inflated tube of air.