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The miracle of 3D printing. First ghost guns, and now ghost rockets. Will be curious to see what prediction markets will have for these.
I wonder how crazy the scale here can get. How far can I go? The bps.space guy is heading into space. Can the community hit the moon? Literally.
I hope this is for students' project and for sending a gopro to the stratosphere?
With the current wars this will only gain more interest.
But hopefully not that kind of interest.

Model rocketry, as a hobby, enjoys a limited amount of regulation, at least in the US. In large part, that is because the community has been very good about self-policing. Most folks who are serious about the hobby closely follow the safety guidelines published by the two national organizations (Tripoli and NAR), and steer newcomers to as well. Serious accidents are few and far between, intentional damage even more so. Compare this to, say, drones, which seem to be more widely embraced by the public, but are much more closely regulated and have been implicated in a number of serious incidents like https://abcnews.com/US/drone-operator-charged-hitting-super-... . Model and amateur rockets are cool. Folks mis-using them are going to run into a lot of pushback from pretty much every direction, because it'd only take an incident or two to ruin the hobby for everyone.

This is pretty cool. I remember having fun simulating my rockets using the BASIC programs from G. Harry Stine's "Handbook of Model Rocketry" when I was a kid. This looks like a way to recreate some of that fun.
Oh i've been looking for a project for my 11 year old... he's a very project oriented learner, which schools don't seem to do anymore.
Is there a similar drone design simulator?
Well THAT's cool. I was just talking about getting back into model rocketry... I'm not sure my 6yo daughter will like it as much as I did/do but I want to get back into it and launch a few and see if she's into it. Timing here is great as I need to start looking at starting from scratch with kits etc.
I read the name and the first logical thought that came to mind was that of a platform to have AI agents iterating on rockets design. How doomed am I?
Why would you put that evil thought into other people's heads? Now someone might do that
Generative AI iterating on design is being done with satellites in production already (and given that there's limited scope for real world testing so you're solving complex optimization problems against a set of models, actually represents one of the better use cases for generative design). Don't think the foundation models and physics based constraints solvers involved look much like LLM "agents", mind you..
I helped out with a user interface redesign of OR many years ago. It was pretty incredibly unintuitive back then, and many hobby rocketeers paid for Rocksim instead.
Im guessing that all the sudden interest in rocketry and drones is related to the war in the middle east? Because I have found that very interesting too, that a country as poor and as heavily sanctioned as Iran is managing to hold out the mightiest human forces the world has ever seen.
What do they hold, exactly? Leaders are dead and keeps dying, good chunk of their military is defunkt, while "mightiest human forces" don't even have boots on ground.
Only someone coming out of the US education system can have both the power to start such a war and the complete lack of knowledge needed to think it would go well...

> a country as poor and as heavily sanctioned as Iran

It's one of the oldest civilization in the world

It's not poor by any means, it's the 20th economy in the world

They produce as many engineers per year as the US, and they're not financial engineers or saas coders, fyi:

> mid-14c. enginour, "constructor of military engines," from Old French engigneor "engineer, architect, maker of war-engines; schemer"

Sanctioned for half a century means they developed other ways to live and survive

We used OpenRocket for designing our rocket for UK youth rocketry competition UKROC[1].

It is great for getting a 'spherical cow in a vaccuum' idea of likely altitude with different motors, centre of pressure, center of mass etc. But it obviously doesn't take account of detailed aerodynamics etc and we found the maximum altitude estimates were about 15% too high. But it was still very useful.

[1] UKROC is an amazing competition for UK school kids. And there are equivalent competitions in the US, France and Japan, with an International competition for the 4 country winners. If you know any kids interested in engineering I recommend you look into it.

https://www.ukroc.com/

> we found the maximum altitude estimates were about 15% too high.

this often happens when the wrong rocket finish is selected. Everyone chooses a polished finish when in actuality they've just sprayed the thing with paint.

Skin drag is real.

I can't find the French competition, ironic given that the front page of ukroc is full of French gov officials... Could you share the name if you have it?
Heh, UK tinkerer here :)

How hard is it to get started for amateurs? Are rules/regulations problematic?

Not hard. Buy an Estes kit. Go along to one of the regional meetings, fly your rocket and talk to people there - they are very friendly.

The UK regulations are fairly sensible and they won't let you do anything stupid at one the regional meets. Just start with something small (A/B/C motor) and work your way up from there. Don't try to start with a K motor, 2 stage or liquid propellant and you'll be fine.

Where are you based?

This application gets used a lot in the High Power Rocketry hobby. Most of the parts/manufactures are included as well as motor manufactures. The simulations are very good and accurate, I would sim my larger builds at the location where i was launching to get an idea of altitude and it was always pretty close ( within 5-10% i'd say ).

I use to have a website where you could upload an openrocket file and get back 2d drawings for your fins that could then be sent to my lasercutting service. The idea was design the rocket in openrocket, send me the file, and get back the wooden pieces you need cut per the design. Similar to sendcutsend but for the rocketry hobby.

Really cool seeing it show up on HN.

Does anyone know of something similar, but for aircraft and/or drones? I’ve been 3D printing model aircraft with my 8-year old but would be great to take it to the next level.
Love to play "Useful program or random startup" with these titles.
There should be an agent for this :D . What kind of tooling do you folks use for simulation ? Maybe there is something to be done there. ?
Software developers: I am begging you to put representative screenshots on the home page. This has become a real widespread problem.

I know you want to tell us all about the amazing (sincerely!) stuff under the hood, but to users, the interface is the product.

Its a nice project !
With CAE and flight simulation, this would be a game that I would actually enjoy playing.
I would recommend checking out your local laws on export of software with military applications. I believe this would be illegal to release in my country (whether that's the right thing is worth discussing, but protect yourself first).

Looks like a pretty mature project though so I suppose it must be on solid ground.

It might also run the risk of breaking IMPORT laws in your respective countries, worth being sure of because that is not a realm of law you want to be messing with.

Our university rocket team uses openrocket extensively for doing fast design iterations early in the design phase. We have also used Rasaero II which is meant to be more rigorous above transonic speeds. We have an Ansys CFD too but that requires significantly more time to set up. We still use openrocket on launch days to do pre launch sims, but we override some of the parameters based on the more rigorous simulations.