GoPro on a Rocket! [VIDEO]

[BagelRabbit]

So.

I'm into high-powered model rocketry. If you don't know about this branch of rocketry, it's sort of like model rocketry but... bigger. You can fly big, heavy payloads a long ways into the air, and return them safely. It's one of the closest real life equivalents to KSP, and I strongly recommend that you check it out.

Anyway, I've created a rocket that can safely loft a GoPro video camera about 1300-1500 ft. into the air, and the results are surprisingly beautiful. I wanted to share this video with everyone, and also to ask: Who's interested in model/high power rocketry?

In the future, I really want to affix one of the Shapeways Kerbal models to the rocket, and watch it go into the wild blue yonder in glorious HD. But I'm getting ahead of myself.

Enjoy --

[The Destroyer]

That's pretty cool!

[astropapi1]

Could... could you help me out with something?

I'm slowly pushing my way into model rocketry, and I want to start making Kno3 rockets, but the nozzles... I haven't seen any good and simple tutorial videos for them. All tutorials either over-complicate them, or simply assume you already know how to make them.

Could you guide me to a nice nozzle tutorial, pleaseeee?

[BagelRabbit]

I want to start making Kno3 rockets, but the nozzles... I haven't seen any good and simple tutorial videos for them.

See, KNO3 rocket motors are technically illegal, unless you get some permits. But, I ask, why even make KNO3 motors? There are a wide variety of motors that you can purchase online or at your local hobby store. They offer a wide variety of different thrust levels. There are even motors that you can purchase, legally and without a license, almost as powerful as the one I flew this rocket on. And, if you get a 'high power certification,' the sky is no longer the limit: Bigger high-power rockets can track up to the edge of the atmosphere, with motors that have been legally made by a prominent manufacturer. (Try Estes or Quest for your smaller motors, and Aerotech/Animal Works/Cesaroni for your higher-power motors.)

Here's my advice to you. Join a rocket organization called the NAR (National Association of Rocketry). Fly your rockets at one of the model rocket clubs that is likely not too far from your home. Look at the rockets they fly there, the ones that are bigger than yours. Ask lots of questions. Gradually, work your way up, until you are flying rockets around the size of the one shown in the video. At this point, you can legally get the permits from a rocket organization called Tripoli. Get into a website called The Rocketry Forum; they have a great 'research motor' section. But as you rise through the ranks of rocketeers, you may find that commercially produced model rocket motors are just as good and fun as their KNO3 counterparts.

Have a nice day.

[Firov]

Could... could you help me out with something?

I'm slowly pushing my way into model rocketry, and I want to start making Kno3 rockets, but the nozzles... I haven't seen any good and simple tutorial videos for them. All tutorials either over-complicate them, or simply assume you already know how to make them.

Could you guide me to a nice nozzle tutorial, pleaseeee?

Heh. These are fun to make. I assume you're talking about KNO3/Sugar rockets, AKA candy rockets?

I made a rocket powered by a "G" class KNO3/sugar engine for my senior project in high school. It actually worked extremely well, considering how I had to machine the motor, design the rocket, and cast the fuel grains. Now that I think about it, I'm kind of amazed my teachers allowed that.

Anyway, what are you making the rocket casing out of? Metal? Or are you trying to use a PVC casing with a graphite nozzle? I used low carbon steel (AISI 1018) for the nozzle and forward bulkhead. I used electrical metallic tubing for the motor casing. However, it's also possible to make "disposable" rockets using a graphite nozzle. Just don't expect it to last through multiple launches.

Take a look at the following link. It's a site run by Richard Nakka, who's about the closest thing to an expert on KNO3/sugar fuel you'll find. I'd suggest taking a close look at the A-100M rocket motor design and test data on there too. It's an excellent starting point for making your own KNO3/sugar rocket motors. Plus, when you're getting started with these, you don't want to jump straight into a large motor. It takes time and practice to perfect your methods for casting fuel grains into the motor casing. Plus, as long as you've got a good recovery system it's reusable, and actually really cheap to run unlike commercial rocket motors.

http://www.nakka-rocketry.net/

Heh. Looking over it now, it looks pretty much the same as when I referenced it for my high school project back in 2006. Still, the information on there is excellent, no matter how old.

Finally, I would be very careful with the fuel mixture when you're casting it. While it might be called "candy rocket fuel", it's not something to be trifled with.

[Halsfury]

Could... could you help me out with something?

I'm slowly pushing my way into model rocketry, and I want to start making Kno3 rockets, but the nozzles... I haven't seen any good and simple tutorial videos for them. All tutorials either over-complicate them, or simply assume you already know how to make them.

Could you guide me to a nice nozzle tutorial, pleaseeee?

I don't know too much about the specifics of homebuilt motors but I did out of curiosity look up some videos of how to make them

Someone suggested that the nozzle be made with "putty" the kind of stuff which some people are driven to repair dents in their cars with

He suggested that you sand the inside of the PVC pipe motor casing and apply the putty to the inside of the PVC (after you put the grain in) He said that you can use a 1/4 inch dowel or something to make a rudimentary nozzle and that for a short span of time you can shape the nozzle to your preference after the exhaust outlet has been established.

Don't take my word for it though, what you do with your own fingers is your own biz, and I'm not liable

(Insert More legal boilerplate as necessary here)

Edit: Just so you know, in the video he lit one of these things and I noticed the PVC piping was glowing orange and expanding slightly under the pressure

Also God only knows how you will come up with a chute ejection system with one of these things, that's the part which worries me most, that you would have to rely on an altimeter or a timer and not have the failsafe of the blast cap at the end of the rocket motor to push out the chute.

Edited December 16, 2013 by Halsfury

[Halsfury]

Forgot to compliment the original poster on his perfect flight,

There are so few high quality cameras on rockets, I enjoyed your little clip better than the hull cam on the Chang'e 3

I wish I had time and more clement weather (-6 C right now and snowy) for launching rockets of my own

Only ever owned one rocket, when I was a kid my dad got me an estes rocket which ran on C3-6's

Mine is still in the basement, I was looking it over the other day thinking thoughts about gutting the motor hold down and friction fitting a G motor muhahaha!

[BagelRabbit]

There are so few high quality cameras on rockets, I enjoyed your little clip better than the hull cam on the Chang'e 3!

Thank you so much These compliments mean a whole lot to me. Good luck on getting the rocket to fly on a G motor.

I'll be trying to launch this rocket at the same time as several others on Saturday - I'll see if I can get footage of the others going off. Wish me luck, and stay tuned!

[Halsfury]

Also after checking the internet for my rocket I noticed that it weighs only 113 grammes

Maybe I'll settle for an F motor, since apparently it has enough kick with a C6-3 to go up over 1000 feet :-)

[Stranded]

Awesome video. You have to love those GoPro's. I had one mounted to my rc glider and had it up high enough that a cloud got between me and the glider obscuring my view. Long story short I nosed it straight in from pretty high up, and the GoPro didn't miss a single frame. It hit the ground and kept on filming. I am guessing you aren't using the suction cup mount.

[BagelRabbit]

Well, I have good news and bad news for you.

The good news? I've got another GoPro video.

The bad news? It's of the rocket exploding.

Shortly after ignition, the forward O-ring could not contain the burning propellant any longer, for unknown reasons. This caused the rocket to separate in two prematurely, and to tumble out of control. As the burn progressed, the rocket began shooting fire out of both ends, burning the cord connecting the two halves. As the GoPro drifted down more-or-less normally under parachute, the other half fell to the ground, still belching flames. Fortunately, this didn't start a grass fire, and no one was hurt.

There's another, nearly identical rocket that I can stick the GoPro on top of. Hopefully, this kind of accident doesn't happen again, and I can safely fly the GoPro for a while longer.

And you thought these things only happened in KSP!

[Halsfury]

:-/ it looked cool though, did the rocket survive?

I had one question which I think you could help me with, I was thinking about what would be required to get a ~25/29mm or slightly larger diameter rocket to hit mach 1 or slightly greater, I've seen this done on youtube with E,F and G motors.

I really need to get drag down on the rocket in order to break mach 1 but I have never found a single thing to indicate what will do the best in terms of nosecone shape.

But what is really messed up is that for subsonic flight the ogive (a parabola) is the best shape, and apparently an ogive is the best shape for supersonic flight as well!

Do they mean that I should have an ogive with a sharp point?

wikipedia tells me that this is an ogive (at the top of the bullet)

But this is an ogive also? what is the best shape?

Edited January 1, 2014 by Halsfury
I'm confused nvm

[Halsfury]

Oh I almost forgot, you might find this interesting… I found a repository of old rocketry magazines from around the time of the Apollo missions.

I thought that a lot of the experiments which amateurs were performing then are interesting to examine, these guys were doing stuff as diverse as trying passive control with ram-air vents, 2 stage supersonic vehicles (on F motors, the biggest available), and building mouse capsules with breathing and heartbeat sensors (don't do it, pita would have a fit).

http://www.ninfinger.org/rockets/ModelRocketry/ModelRocketry.html

Some of it is very 70's and ridiculous but other stuff (like the ram-air vents research) generated interest in the air force

one of the better publications in terms of interesting stuff was July 1970, this is because MIT had a symposium of sorts on rocketry which was covered extensively, as well as drawings for an R-7 vostok/sputnik missile

Edited January 1, 2014 by Halsfury