LSF Rocketry Librelaunch!


#1

Hi. For those who don’t know me I am Jo aka concretedog and I am passionate about rocketry. I do lots of stuff on rocketry from designing opensource low and high power rocket designs https://gitlab.com/concreted0g/ODR to running workshops on rocketry, design and simulation for free in UK maker spaces. I also sit on the UK rocketry council (cross certified equivalent of NAR or Tripoli in the UK) which maintains the UK safety codes and insurance for high power rocketry and runs the certification schemes etc.

I am totally inspired by projects such as Copenhagen Suborbitals and the DARE rocketry team at TUDelft but I feel that we should build an opensource rocketry movement. Copenhagen Suborbitals do push the development of opensource tools (as evidenced by @csete great talk at OSCW18) but they aren’t open sourcing the designs of the rocket airframes and hybrid motors. DARE are an amazing example of student rocketry and but equally they are not open source and also take a lot of sponsorship from prime aero companies (airbus, thalia etc) which means that (to my mind) they are supported and by implication supportive of the development of space technologies using defence company funding.

I think it’s high time for a real push to build on the excellent work already undertaken by the LSF core team activities on building the LSF rocket avionics boards and the cansat rocket launches they undertook some time back. I am totally up to offer whatever knowledge and experience I have gained and have also offered that I am happy to integrate any tech we develop into my personal high power launches so stuff can be tested at high g and with some altitude.

I’m also prepared to write some posts and collate links and reading on rocketry if people from the community want to engage but need to know some fundamentals… suggest to me what would be useful to know and I’ll endeavour to find resources for you.

I’d love for this to lead to a long road-map where we create a decentralised community pulling together and working on launch vehicles that are open source and outside of the defence development model… you know… getting to space the libre way :heart_eyes:


#2

Thanks @concretedog for this call to action! I’m +1000 on starting to do real open source rocketry. Regarding Copenhagen Suborbitals, I found a news article from 2013 that links to a download file, but returns 404 even on web.archive.org:

Do you think some of the work from Portland State Aerospace Society can be reused? It even has CAD files, although in SolidWorks format (I’ll open a separate thread for the tooling):

While Googling, I found a couple of other interesting links, although these efforts seem abandoned:

I understand that ODR is a solid fuel rocket. From your experience, what would be the most important/challenging part to begin with? The structure, the nozzle?


#3

Hey @astrojuanlu thanks for responding. The PSAS stuff is great and I have seen it before and keep an eye on their developments. I have fixed the ODR link in the original post so you should be able to click through now!

ODR is designed to fly on 38mm COTs motors by either Cesaroni or Aerotech which are currently the only manufacturers of motor available for high power rocketry in the UK. In the UK it is totally illegal to try and make any type of solid rocket motor and therefore we don’t! In the US this is different and I often see homebrew solid rocket propellants (SRP’s) being developed tested and flown. Here in the UK we are allowed to develop experimental hybrid motors (where you push an oxidiser through a solid fuel grain), this is essentially what the TUDelft DARE rocketry team are doing. Hybrid motors are interesting and pretty safe to develop and have the advantage over solid motors in that it is possible to throttle them.

It’s also possible in the UK to develop, test and fly bi propellant engines (what many commercial rockets fly) these are invariably more complex but again have the throttling capability and a range of oxidisers and fuel types that can be utilised. I have done some works using a paper https://www.amazon.co.uk/DESIGN-BUILD-LIQUID-FUEL-ROCKET-ENGINES/dp/B005D3P30Q (this paper widely available as a pdf online) and have a spreadsheet that can give you dimensions and other variables of an engine design if you throw the chamber pressure and thrust you desire in! Its here if you want to play! https://gitlab.com/concreted0g/FOS_Engine_design

Regarding nozzles… it depends what we are building… for simple laval type nozzles they are simple to turn on a lathe from steel or from graphite and for bell type nozzles they can be realised via a cnc lathe or in graphite by using form cutters… I’ve played with this on my machines with reasonable success.

I also have a few other resources online including a quick and dirty walk through getting started designing and simulating a small rocket in the brilliant Openrocket which is a great opensource tool for rocketry. repo here https://github.com/concretedog/openrocket_getting_started_walkthru

Happy to answer any and all questions!


#4

First Lego League this year is all about ‘Into Orbit’. I’m doing the STEM thing with the local primary school with their team. Anything we could offer for that?

Water rockets are fun but something with fire and flames is more fun


#5

Hey @g7kse totally up for helping you do something cool for the school… my kids often make me launch minifigs etc for them! Remind me in PM whereabouts you are based as also we might have UK rocketry people near you who might offer services. Even if not happy to discuss ideas and make suggestions on small rocketry stuff you might be able to do/launch.

In the UKRA we also have the Model Achievement Program (MAP) … its a progression route with a syllabus taking young people through varied model rocket activities… its quite a commitment for young people and organisers but some groups love working through it.


#6

I’ll have a look at the MAP stuff. This is the first time I’m involved with FLL, they have a project a code of conduct and some lego mindstorms stuff to do. I wanted to do a SatNOGS 70cms GS with them but I think that’s a bit too much so was thinking about designing and building their own rocket as an option. In the end they’ll decide what they want to do.


#7

I too am both a rocket and open source enthusiast. I currently build and fly model and high power rockets under NAR rules in the US. I hold a high power level 2 certification under those rules. I’d be very interested in joining a discussion regarding the advancement of open source rocketry projects including those already started by LSF.

Steve


#8

Hey @ssaner thanks for responding… Its great that we now have at least 2 HPR flyers here! I’m wondering if for example if we pushed on some avionics projects building on LSF existing platforms we then have some decentralised people in a position to do some test flights! Do you fly from a regular club/event? I’m jealous of the scene and availibility of stuff in the US…wish it was like that here! I’m currently on L1 but planning an L2 build and flight this summer.


#9

Hey Jo,
Just saw your tweet. I personally have no experience in rocket building but if you need help making an rocket guidance / general avionics & comms I would love to help. Some amateur liquid rocket tests would be awesome!

Let me know!

Cheers,
Julian