[Ground-station] Call for discussion: ORI satellite program

[Phil Karn]

On 4/22/18 19:00, Bruce Perens via Ground-Station wrote:

> I don't know anything about satellites. I am trying to rectify that
> issue as fast as possible,

Don't underestimate the value of experience. As hidebound as AMSAT may
have become, they do have a track record that began long before the
cubesat era. In fact, the cubesat idea was invented by Bob Twiggs
operating more or less under the broader amateur satellite umbrella.

Satellite engineering is inherently multi-disciplinary; that is in fact
a lot of its value to engineering education. Lots of skilled people are
needed beyond the obvious electrical and computer engineers. A gap in
expertise can cause an entire project to fail because of overlooked
problems. Classic example: thermal design. A satellite in space is its
own little planet with its own radiation balance, just like the earth.
The physics is well understood, it just takes an engineer who
specializes in that stuff (usually mechanical or aerospace) to apply
their skills. I understand the basics, but EEs at Cornell were not
required to take thermodynamics so I didn't.

> One thing that has struck me about AMSAT is that they have so far
> operated with only NASA as their launch partner,

That's not actually true. Several major satellites with major AMSAT
North America involvement flew on the European Ariane, such as Phase
III-A, Oscar-10, Oscar-13, the Microsat constellation (Oscars 16-19),
Oscar-40 and probably some others I've forgotten. Numerous cubesats with
various degrees of AMSAT involvement have flown from Ukraine and
probably Russia, India and Japan. Only China (and North Korea) are
excluded for political reasons.

I did the telemetry system for ARISSat-1, deployed from the ISS in 2011.
It was designed and built in the US but launched to the ISS on a Russian
Progress, deployed by Russian cosmonauts during an EVA and operated
under a Russian name (Kedr), license and callsign. (And the Russians
gave us virtually no credit, which really pissed me off.)

But cooperation between US AMSAT and the rest of the world has
definitely diminished in recent years because of ITAR phobia.


> and they've always
> built a satellite only after there was a clear launch opportunity.

This *is* a problem. Traditionally they get a launch opportunity with
*just* enough time to build something *if* the launch schedule slips (as
it almost always does). Then there's a mad rush to get the hardware to
the launch pad. Software is invariably an afterthought, often literally
sent up after the hardware.

So AMSAT rarely does anything truly new, because they never allow
themselves the opportunity to develop stuff so it can be ready when the
launch opportunity appears. Like interesting digital stuff. (I've
already let it be known that I'm simply uninterested in doing another
telemetry system for a primarily analog satellite.)

> So, my idea was to run an "Opportunistic" satellite program, in which we
> would construct cubesats and P-pods without a clear launch opportunity
> in advance, and then approach commercial launch providers (and others)
> with ready-to-fly equipment in hand when opportunities come up.

I'd go farther than that -- an applied research program to develop and
prove (on the ground) novel (to hams) concepts so they can be ready for
actual development when the opportunity appears. The initial hardware
need not even be intended to resemble anything we could fly; it would
just be a proof of concept.
> We can also make better academic partnerships. Fully 50% of academic
> cubesats fail, due to lack of experience, poor component choice and
> engineering decisions, and because they don't understand radio well.

Or thermal engineering...or mechanical structures, or lack of knowledge
of aerospace design standards...

> There is also the issue that University projects aren't well equipped to
> continue to control the satellite over a period of years, and that FCC
> doesn't want paid employees as satellite licensees or operators if
> they're licensed in the Amateur service.

Correct. This has been controversial in some quarters but I can't think
of a more worthwhile use of the ham bands than to support science and
engineering education. I don't care if they're university students or
individuals puttering in their basements.

Where we have to be careful is when the main purpose of the satellite is
as a "bus" to support some large science project or commercial
engineering project, and the satellite operator is just after us for our
spectrum. There has to be a significant ham (and educational) component.

> So, my thought was to partner with universities and to provide them with
> finished cubesats with room for their experiment, using Karn's modem
> rather than the poor AX.25 implementations they usually use, and
> operating the satellite for them after launch. They would get the launch
> and run their experiment. The satellite would be a hamsat during or
> after the experiment.

There's already a flourishing cottage industry supporting cubesats. If
you've got the money, you can buy everything you need to support some
experiment.

For example, I think ISIS (bad name choice) will sell you a complete
attitude control system for about $200K (the last time I checked). This
is not only outside of our budget, it bothers my sensibilities as a ham.

What drew me to AMSAT in the early 1980s were truly clever hacks like
stabilizing satellites with bar magnets and painting measuring tape
antennas white and black to spin them with solar photon pressure. W1HDX
once designed a 137 MHz circularly polarized APT patch antenna out of a
4'x8' sheet of Home Depot polyurethane insulation with aluminum on both
sides. You lay it on your roof, paint it to match and nobody in your
neighborhood will even know you have a prohibited outdoor antenna. This
is ham ingenuity.

Unfortunately, these great hacks are getting a little long in the tooth.

Momentum wheels and control electronics simply shouldn't cost that much,
and we need to use our brains to figure out how to do it cheaper and better.

Phil


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