OpenRocket

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/

There is also the rocketpy framework. https://docs.rocketpy.org/en/latest/index.html

Essentially it can do the same thing as openrocket, but in python. You can even go as far as to simulate liquid fueled rockets during flight, modeling for example how the depleting tank influences the center of mass. My student rocketry team used this for the flight simulation of our Ethanol/Liquid Oxygen rocket which flew to over 5km

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.

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.

Tangentially related is NASA's open source GMAT[0] software which is more focused for calculating orbital transfers and the like. It's pretty fun to play around in.

[0] https://software.nasa.gov/software/GSC-18094-1

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.

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.

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 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.

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?

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.

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.

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.

What about misuse for weapon development? Does the project not massively cut R&D costs (hence lowering the entry hurdle) for potentially malicious actors on the planet?

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.

The miracle of 3D printing. First ghost guns, and now ghost rockets. Will be curious to see what prediction markets will have for these.

With CAE and flight simulation, this would be a game that I would actually enjoy playing.

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.

With the current wars this will only gain more interest.

Love to play "Useful program or random startup" with these titles.

I hope this is for students' project and for sending a gopro to the stratosphere?

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. ?

Is there a similar drone design simulator?

Its a nice project !

you gonna need them!

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Bookmarked :)