[Ground-station] Satellite program
Jonathan Brandenburg
jonathan at jonathanbrandenburg.com
Wed May 30 04:55:16 PDT 2018
I'm available for the proposed meeting,
jb
On 5/28/2018 2:50 PM, Michelle Thompson wrote:
> I think this is very good news and has enormous potential across many
> projects.
>
> One of the action items from Hamvention was to set up a repository
> structure for P4S that mirrors the payload projects we are beginning
> to become associated with (UPSat, etc.). One of the top level
> divisions is, of course, IHU. No time like the present to get that done.
>
> We will set this up today and invite everyone referenced here as
> maintainers. If we can get a copy of the documentation pegged, then we
> can start moving forward from there. Other options, like the Vorago,
> can be documented and discussed in parallel.
>
> Wide review and evaluation can further improve an already good design.
> I know there's a lot of opinions and feedback surrounding this design.
> I know some discussions happened at 2017 Symposium and there has been
> plenty of work done since then.
>
> Jonathan et al, do you think a conference call about the IHU would
> help? I was thinking Thursday 6pm Pacific might be good.
>
>
> -Michelle W5NYV
>
> "Sit vis vobiscum."
>
>
> On Mon, May 28, 2018 at 10:14 AM, Jonathan Brandenburg via
> Ground-Station <ground-station at lists.openresearch.institute
> <mailto:ground-station at lists.openresearch.institute>> wrote:
>
> [I'm speaking a bit for Zach Metzinger, so I've copied him on this
> email. I'm not sure if he's on this mailing list or not and want
> him to be in a position to expand or correct my statements, or
> even disavow anything I'm saying, if he desires.]
>
> A small team, primarily Zach Metzinger with the assistance of
> others (Bill Reed, Jordan Trewitt, me), is designing an IHU based
> on the TI Hercules safety-critical processor. While the Hercules
> is not necessarily radiation-hardened, the processor is designed
> for operation in very noisy environments. It's also designed to
> detect faults, by executing instructions on two cores in lockstep,
> detect when the result differs, and signal a failure. (I imagine
> there are other features, but this is a high point.)
>
> So, we've been designing an IHU with two Hercules processors and
> two digital transceivers configured in a fail-over configuration
> along with redundant power circuits. There's still work to be
> done, but Zach has begun laying out this board in a 1U footprint.
>
> [This is the part where I'm speaking for Zach...] I believe Zach
> is committed to ensuring this design is open and available. As a
> result, I expect we'll be quickly publishing this work (by
> ITAR/EAR definitions) as we achieve milestones. This IHU work was
> begun before the AMSAT Golf program was kicked off and is now
> being integrated into Golf. I don't know of any reason this work
> couldn't be leveraged and used in other satellites.
>
> Thus, I submit this IHU-in-progress for our consideration...
>
> Jonathan Brandenburg
>
>
> On 5/16/2018 1:54 PM, Bruce Perens via Ground-Station wrote:
>>
>> Legal stuff first: Image credit: XKCD #1992: "SafetySat" at
>> http://xkcd.com/1992/ Creative Commons Attr-NC 2.5 license.
>>
>> Yes, we should have a satellite program and do what AMSAT is not.
>> Everyone I have heard from so far is asking for a "DX Satellite",
>> "like AO-13" and not LEO.
>>
>> Mission should include digital communications using Michelle's
>> design. I also have some blue-sky ideas that we can discuss at
>> Hamvention, some of them might be good grant candidates. Think
>> grant. Money is out there, we will start soliciting as soon as we
>> have a mission plan.
>>
>> Build the satellite (and maybe P-pods) first, approach launch
>> providers with flight hardware in hand and ready to go.
>> Satellites are cheap, launches are not. Be prepared to take
>> advantage of opportunities on very short schedules.
>>
>> I think we should fabricate extras of parts we design, and sell
>> them as TAPR does to supplement their budget, but right off of
>> Amazon Prime. Make them really easy and fast to buy, and someone
>> else does the shipping. Aim at flight-quality but mostly going to
>> classroom use rather than flight, to start. Nicer for the class
>> than the PLA 3-D printer stuff that is so obviously non-flight
>> that they are using now.
>>
>> Aim for 100% to 200% markup over cost, Amazon gets around 18% of
>> the order and a warehouse fee and fulfills from their warehouse.
>> Most of the commercial cubesat companies, like Pumpkin, are
>> running 500% to 1000% markup in order to amortize R&D and
>> operational costs and still make a profit, but most of them have
>> flight heritage that we would not start out with. We use slave
>> labor :-) and can mostly base our final cost on fabrication and
>> sales costs.
>>
>> I have been looking at cubesat structures (because I feel
>> competent enough to make one, at least with your help) and I
>> really like Pumpkin's design. Almost all laser-cut 5000-class
>> sheet aluminum, bent on a brake, anodized corners on the sheet,
>> only the 8 corner pieces are machined, and that only simple
>> shaping and drilling of bar stock into a simple rectilinear shape
>> with specified-radius corners and edges and a place to put the
>> springs and cutoff switch pins. Most other designers seemed to be
>> more interested in showing their skill in CNC machining than
>> making a practical structure. If you look at Pumpkin's stuff, it
>> is clear that they put a lot of thought into mechanical
>> engineering. And they actually engineered for cost and
>> mass-production, while few others bothered. We will not ever
>> directly copy anything (I am an intellectual property specialist,
>> and will keep us legal), but we can and should learn from their work.
>>
>> Besides the structure, other non-mission-specific stuff we should
>> be building would include an IHU (computer) and the other general
>> bus components: lithium battery pack with heaters and per-cell
>> management, magnetorquer, solar panels (what cells, from where?),
>> maybe some heat distribution components like adiabatic heat pipes?
>>
>> Can we hear from volunteers for any of this?
>>
>> LIME mini might be a good flight candidate, besides Ettus and
>> Rincon. Their CEO and Open Source guy are very friendly and their
>> PCB design may already be licensed appropriately. No idea how the
>> chip would take radiation.
>>
>> We should look into the Open Source finite element analysis and
>> CFD programs. We should simulate as much as possible before going
>> to thermal vacuum, vibration and shock, etc. And publish all
>> input data so that it can be reused along with our part designs.
>>
>> I saw a really nice indium electronic thruster at Cal Poly. All
>> proprietary, of course. Goes up with the fuel solid, gets heated
>> in flight. No moving parts, works by wicking through a sintered
>> tip. Probably very patented. But a source of ideas.
>>
>> Thanks
>>
>> Bruce
>>
>>
>> On Wed, May 16, 2018, 09:23 Michelle Thompson
>> <mountain.michelle at gmail.com
>> <mailto:mountain.michelle at gmail.com>> wrote:
>>
>> Heh! The SDR really ties it all together in your sketch there.
>>
>> Yes, there's interest in building an open source satellite.
>> The time is right and we have the best chance of making it
>> happen that I've seen in a long time. There's a variety of
>> forces at work in the industry, in academia, and in open
>> source culture and achievement that help make a modern,
>> innovative, amateur, open source payload possible.
>>
>> I don't know enough about MEO but I'm game for supporting any
>> payload that enables an enduring amateur community through
>> reliable communications in space. I'm very happy we get the
>> chance to dig into this and I want to enable and support it
>> as much as possible.
>>
>> The Careful COTS of an Ettus USRP effort is one way to get a
>> capable SDR for space. This is a joint project between Phase
>> 4 Space and GOLF to get the E310 in play soon/now for GOLF
>> and the E320 later for Phase 4 Space. Business unit at Ettus
>> is reviewing it. Systems engineering lead for GOLF endorsed
>> it as an open source effort. Meeting minutes were posted to
>> the list. Next steps depend on what IP from Ettus. We'll
>> proceed with the E320 as far as it takes us regardless. I
>> expect to make a lot more progress here in late summer/early
>> fall, especially at GNU Radio Conference 2018.
>>
>> The Rincon AstroSDR is another option, and Rincon has reached
>> out with questions and clarifications in response to the
>> Kittens Weekly Report. There will be more talks after
>> Hamvention. Rincon will be a significant presence at GNU
>> Radio Conference 2018.
>>
>> Propulsion, attitude control, solar power, and a variety of
>> antennas all have open source flight-tested options at LEO. I
>> don't know much about navigation.
>>
>> I do know that we have a lot of support out there from
>> like-minded organizations and projects.
>>
>> I do know that a payload design is within the capabilities of
>> people on this list and within our extended
>> Slack/GitHub/phone/email/club/conference network. That does
>> not mean it's easy by any stretch, and it means that our
>> economic development team will be tested. I think we are up
>> to the challenge.
>>
>> What's the first thing that you think we need to do?
>>
>> -Michelle W5NYV
>>
>>
>>
>> ---------- Forwarded message ----------
>> From: Howie DeFelice <howied231 at hotmail.com
>> <mailto:howied231 at hotmail.com>>
>> To: "ground-station at lists.openresearch.institute"
>> <mailto:ground-station at lists.openresearch.institute>
>> <ground-station at lists.openresearch.institute>
>> <mailto:ground-station at lists.openresearch.institute>
>> Cc:
>> Bcc:
>> Date: Wed, 16 May 2018 04:16:15 +0000
>> Subject: Satellite Building
>> Just wondering if there is interest in putting together a
>> project to build a satellite. There is no particular
>> launch in mind and no particular mission at this pint
>> other than the generic Amateur Radio goal of furthering
>> the art of communication. I think most will agree that
>> the LAST thing we need another LEO. To simply exploit the
>> microwave bands I think we want to consider orbits that
>> allow hours of coverage at a time. A GEO would be great,
>> a HEO would be really good. An overlooked orbit, at least
>> in ham radio, is MEO. An orbit between 8000 and 10,000 Km
>> would provide about 2 hours of coverage and orbit the
>> earth about twice a day. The problem is that not too many
>> people fly there so we need another strategy. If we
>> aren't in a big hurry, maybe we can get there from LEO.
>> This means we need propulsion, attitude control,
>> navigation, lots of solar power and a really cool radio.
>> Does this sound reasonable? How long would this actually
>> take with a milli-Newton thruster ? I have attached a
>> sketch of my first ideas.
>>
>> - Howie AB2S
>>
>>
>> ---------- Forwarded message ----------
>> From: ground-station-request at lists.openresearch.institute
>> <mailto:ground-station-request at lists.openresearch.institute>
>> To:
>> Cc:
>> Bcc:
>> Date: Wed, 16 May 2018 00:16:18 -0400
>> Subject: confirm db1d86455ef4eb7857a41676b75024137549ff1d
>> If you reply to this message, keeping the Subject: header
>> intact,
>> Mailman will discard the held message. Do this if the
>> message is
>> spam. If you reply to this message and include an
>> Approved: header
>> with the list password in it, the message will be
>> approved for posting
>> to the list. The Approved: header can also appear in the
>> first line
>> of the body of the reply.
>>
>>
>>
>>
>> _______________________________________________
>> Ground-Station mailing list
>> Ground-Station at lists.openresearch.institute
>> <mailto:Ground-Station at lists.openresearch.institute>
>> http://lists.openresearch.institute/mailman/listinfo/ground-station
>> <http://lists.openresearch.institute/mailman/listinfo/ground-station>
>
> --
> Jonathan Brandenburg
> 1-214-213-1066
> jonathan at jonathanbrandenburg.com
> <mailto:jonathan at jonathanbrandenburg.com>
> -----------------------
> When possible, please sign and encrypt your communication. See https://ssd.eff.org
>
> I updated my PGP certificate on December 8, 2015. Please update your keychain:
> PGP certificate fingerprint: 824E 8871 5474 61F7 09D4 9B67 8AFC 1E70 924D B20
>
>
> _______________________________________________
> Ground-Station mailing list
> Ground-Station at lists.openresearch.institute
> http://lists.openresearch.institute/mailman/listinfo/ground-station
> <http://lists.openresearch.institute/mailman/listinfo/ground-station>
>
>
--
Jonathan Brandenburg
1-214-213-1066
jonathan at jonathanbrandenburg.com
-----------------------
When possible, please sign and encrypt your communication. See https://ssd.eff.org
I updated my PGP certificate on December 8, 2015. Please update your keychain:
PGP certificate fingerprint: 824E 8871 5474 61F7 09D4 9B67 8AFC 1E70 924D B20
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openresearch.institute/pipermail/ground-station-openresearch.institute/attachments/20180530/5aaeef9e/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: OpenPGP digital signature
URL: <http://lists.openresearch.institute/pipermail/ground-station-openresearch.institute/attachments/20180530/5aaeef9e/attachment.sig>
More information about the Ground-Station
mailing list