It was posible to launch Apollo 11 with less powerful electronics. Mechanicaly it is a bit expensive but many 'amater' clubs achive controled flight, a few to the edge of space.
Ask HN: Is it practical to create a software-controlled model rocket?
11–20 of 78 posts
Re: Ask HN: Is it practical to create a software-controlled model rocket?
#12You may be interested in following Tom Stanton on YouTube. He built a radio controlled SpaceX model a few months ago.[1] It was barely controllable, and wasn't designed with actual propulsion engines, but still very cool.
As others have been commenting, it's a completely different ballgame if you want to use propulsion engines and still be able to land it. At that point, you're just building a smaller version of the real SpaceX rockets, and that sounds much more difficult (not to discourage anyone from trying!).
Re: Ask HN: Is it practical to create a software-controlled model rocket?
#13I can't speak to anything legal, that's its own topic.
But for all the model rockets I've seen, their mass ratios are quite small, and their motors don't allow for throttling. They blow their load as fast as they can and then drift down.
Software is not the biggest problem, you need a hobby quality throttling and gimbaling rocket motor, and I'm not sure if they even exist.
Re: Ask HN: Is it practical to create a software-controlled model rocket?
#14I’m pretty sure that your problem isn’t going to be the software but rather the engine and the rocket itself. Hobby rockets use simple solid fuel engines you’ll need to build an actual liquid rocket engine with controlled thrust that can be reignited the rocket it self also need to be large enough to be aerodynamically controlled and hobby rockets tend to be too light so they’ll simply tumble in the wind. While you d…
It’s undesirable for many reasons but could a small rocket be made to work if you made it really heavy? Of course one would be just pissing away efficiency but would a small heavy software-controlled model rocket work?
Define small, you still need a rocket with some sort of liquid fuel engine with some sort of throttle control and I'm not sure how small can you actually scale those to be.
You might be able to do it with a hybrid rocket engine where the oxidizer is liquid or gaseous but the fuel is solid but I'm not sure.
As for the weight if you make it small but heavy then you are likely to lose aerodynamic control since it essentially will be a free falling brick.
You need something that is massive enough to resist the wind but have a large enough surface area to be aerodynamically stable and controllable, I'm not saying it's not possible I'm just saying that the time and money that you'll have to invest in it is going to be quite likely astronomical and while I don't doubt that there might be individuals that might be able to do it on their own this likely would require a pretty large team of dedicated people to solve.
If you are capable of building a rocket engine I would actually focus on simply building a hovering rocket rather than trying to land it, or at least you better off trying to build a hobbyist grasshopper https://en.wikipedia.org/wiki/Grasshopper_(rocket) than a Falcon 9.
But realistically even for something like this you should be better prepared to spend the better part of a decade building it and likely at least a few $100K's in funding since none of this is going to be cheap to produce.
Re: Ask HN: Is it practical to create a software-controlled model rocket?
#15Be really careful. Adding guidance to a hobby rocket may classify it as a missile, and you will need to start looking into ITAR.
This is immediately where I jumped to as well. A little too close to missile guidance if you ask me... likely to be illegal.
Re: Ask HN: Is it practical to create a software-controlled model rocket?
#16Be really careful. Adding guidance to a hobby rocket may classify it as a missile, and you will need to start looking into ITAR.
A hobby grade throttling and gimbaling rocket engine, with free documentation and open source guidance software sounds like an absolute proliferation nightmare scenario.
Re: Ask HN: Is it practical to create a software-controlled model rocket?
#17If you dig up archives of Armadillo Aerospace - John Carmack's rocket company - you'll see videos of smallish rockets doing just that. "Smallish" as in "you can lift one from the ground, fueled, with your hands... perhaps".
Re: Ask HN: Is it practical to create a software-controlled model rocket?
#18Be really careful. Adding guidance to a hobby rocket may classify it as a missile, and you will need to start looking into ITAR.
Indeed. I have not looked into rocketry for a while, but my recollection is that an active guidance system, active control surfaces, an IMU, all place you squarely under ITAR. Building, much less exporting, without a license is likely a Bad Idea unless you are looking for a Club Fed vacation.
Re: Ask HN: Is it practical to create a software-controlled model rocket?
#19Maybe try with electrical propulsion like this one [Ikarus electric "rocket" - Thrust-vectored flying ducted fan] https://www.youtube.com/watch?v=RMeEh5OUaDs
Re: Ask HN: Is it practical to create a software-controlled model rocket?
#20You will blow up several engines if you try to make a liquid fueled engine. Get yourself a copy of
https://www.amazon.com/Rockets-Missiles-Men-Space-Definitive...
which is the story of a German rocket club which first got shut down by the Nazis because "somebody could get hurt" and then the Nazis thought it over...
Probably your best bet is a hypergolic monopropellant such as hydrogen peroxide.