[HN Gopher] Thrust Vectoring at Model Scale
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Thrust Vectoring at Model Scale
Author : tosh
Score : 127 points
Date : 2020-10-25 17:00 UTC (6 hours ago)
(HTM) web link (bps.space)
(TXT) w3m dump (bps.space)
| 60Vhipx7b4JL wrote:
| $350 for the controller PCB is a bit high. Is the software even
| open source or not?
| wtallis wrote:
| The $349 price shown at https://bps.space/shop/signal-r2 is for
| more than just the controller PCB. See the "IN THE BOX" section
| of https://bps.space/signal/
| marcinzm wrote:
| Seems to be a commercial product, given the small market the
| price seems reasonable since development cost doesn't go down
| but the number of units it gets spread across does.
| 542458 wrote:
| Is it a commercial product? I'm under the impression that
| what this enables (slow thrust vectored ascent of small
| rockets) is extremely cool from a hobby perspective as it's
| more "accurate" to how large rockets work - but from a raw
| functionality perspective for small rockets you're probably
| better off just using faster motors and fins to stabilize.
| marcinzm wrote:
| Commercial meaning it's being sold for profit and
| manufactured to be sold for profit. The market is die hard
| hobbyist but the product is a commercial venture selling to
| those hobbyists.
|
| edit: Versus an open source project or someone's hobby
| project just being sold at cost.
| jcims wrote:
| That's probably $.10 per hour for his time in it if the
| hardware was free.
| showerst wrote:
| I can't seem to find a cite for this (may have been in a video)
| but I remember Joe being asked about open source, and he
| responded that he'd like to but rocket stability and especially
| guidance software is an absolute legal minefield in the US.
| bri3d wrote:
| Yes, he mentions frequently that he's concerned about ITAR.
| Under a strict reading of the Munitions list and ITAR
| regulations, rocket guidance software is a Category IV
| Munition and can't be exported. Unfortunately (as we learned
| from the crypto wars of the 1990s, when strong encryption was
| also a Munition), the US government takes quite a strict view
| towards the consideration of online-available source code as
| "export."
| noir_lord wrote:
| Print it in a book and take the physical copy with you on a
| plane, iirc that was how they did it with GPG back in the
| day because 1st amendment protection.
|
| Been a while so I might be wrong.
| arthurcolle wrote:
| Aren't you not allowed to add guidance to model rockets because
| it starts to be considered a guided munition, i.e. missile?
| dragonwriter wrote:
| If you don't put guidance on it, it's a ballistic missile.
|
| Though for any reasonable model rocket a _very_ short-range
| ballistic missile.
| pietroglyph wrote:
| Joe Barnard (the guy behind BPS.space) has some great videos
| behind the controls involved in this project on the BPS.space
| channel: https://www.youtube.com/channel/UCILl8ozWuxnFYXIe2svjHhg
|
| He also has a ton of other really great talks on controls
| engineering on his main channel.
| roughly wrote:
| I love these kinds of projects. Think about how much of the
| technology in use here was out of reach for the average person
| even a decade ago - the sensors, microprocessors, 3D printer &
| rapid prototyping. The amount of magic we can leverage for hobby
| projects these days is genuinely inspiring to me.
| s4n1ty wrote:
| I've been following Joe Bernard's YouTube videos for a few years,
| he's really great. Goes into a lot of detail about how he
| designs, builds, and flies thrust-vectoring model rockets.
| nyx_ wrote:
| You know the toys you're shopping for are the coolest when the
| webpage says their sale is restricted to US citizens and
| residents only. Is that an ITAR thing?
| microcolonel wrote:
| The Trump Administration seems to have significantly loosened
| ITAR for almost everyone (IIRC primarily intended to make it
| less onerous for small arms researchers and manufacturers),
| including individuals, and specifically addresses removing some
| forms of software and designs from the USML. If it's firmware
| or designs as far as I'm aware there may be no problem with
| that now, even if it's rocketry or guidance software.
| chrisdalke wrote:
| Yeah, ITAR restricts export of guided rocketry systems, which
| this qualifies as. He's mentioned ITAR in some of his videos as
| one of the reasons he doesn't distribute his firmware or
| schematics.
| Animats wrote:
| Here's a 13 year old girl's guided model rocket.[1] It's a moving
| fin system, so there's not much control until it picks up some
| speed after launch. Then it stabilizes and goes straight up.
|
| [1] https://youtu.be/kTND_wot9zI
| tjomk wrote:
| All of the comments under video say it's not guided but rather
| stabilized.
| bronco21016 wrote:
| Yeah, pesky .gov has a problem with "guided" projectiles.
| Stabilized systems rather than guided systems keep you out of
| legal trouble.
| Animats wrote:
| That seems to be an urban legend. There are regulations on
| size and power of model rockets, but not on guidance, at
| least in the US.[1]
|
| [1] https://www.nar.org/find-a-local-club/section-
| guidebook/laws...
| bri3d wrote:
| The regulations are not rocketry/FAA/explosives
| regulations that the NAR deals with, but rather munitions
| export regulations. Specifically, guidance systems are
| munitions and therefore are regulated under ITAR Category
| IV, which means a US resident cannot export the
| technology by, for example, putting it in a public GitHub
| repo.
|
| https://www.govinfo.gov/content/pkg/CFR-2016-title22-vol1
| /xm...
| handol wrote:
| Is this missile guidance system a weapon in the eyes of
| the law?
|
| The feds haven't busted down my friends door for
| contributing yet.
|
| https://github.com/MuMech/MechJeb2
| jcims wrote:
| If you're into any of the stuff at all, I'd highly recommend
| Joe's YouTube channel. He's just a consummate professional, very
| high standards of quality, and very deliberate and methodical
| about development of this technology.
|
| He's since started working on the next generation flight
| controller/avionics platform: AVA. He's wrapping up the first
| iteration of a dual motor retro-rocket landing capability and
| it's possible we'll see the first propulsively landed solid-fuel
| (!!!) rocket flight yet this year.
| detritus wrote:
| Seeing these attempts at model-scale, I'm minded of Elon Musk's
| assertion that 'things get easier to control the larger you go'.
| If that's the case - and intuitively it certainly seems so - the
| future looks fairly bright where orbital insertion, and returns,
| are concerned.
|
| - ed
| [deleted]
| lawrenceduk wrote:
| Really enjoyed the video showing the spectacular failures in the
| build up to getting it right.
|
| Turns out rocket science is hard.
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