The SDUTTsat, a tiny satellite system of my own design!

[KAL 9000]

If you haven't already, see the Femtosats thread where I came up with the idea. This thread is for you guys to offer suggestions and criticisms for the idea and its details, as well as to comment on my proposal in general.

The SDUTTsat is a tiny satellite. (SDUTTsat stands for Super-Duper-Ultra-Teensy-Tiny-satellite) It's really just a computer chip with a tiny solar panel for power and a small antenna for communications. It could carry small sensors, more antennas to make it a tiny communications satellite, or anything really within the size limit. A Cubesat could release it, or it could be mounted on a tiny rack with springs on an upper stage, to be jettisoned once it reaches orbit.

[PB666]

2 hours ago, KAL 9000 said:

If you haven't already, see the Femtosats thread where I came up with the idea. This thread is for you guys to offer suggestions and criticisms for the idea and its details, as well as to comment on my proposal in general.

The SDUTTsat is a tiny satellite. (SDUTTsat stands for Super-Duper-Ultra-Teensy-Tiny-satellite) It's really just a computer chip with a tiny solar panel for power and a small antenna for communications. It could carry small sensors, more antennas to make it a tiny communications satellite, or anything really within the size limit. A Cubesat could release it, or it could be mounted on a tiny rack with springs on an upper stage, to be jettisoned once it reaches orbit.

Launch it with a blimp, heh-heh, use anti-hydrogen, once the blimp reaches maxim volume, caboom your at alpha centauri.

Oh, you want helpful suggestions.

[wumpus]

The Devils in the details.  The obvious details from someone who has never built a [non-KSP] satellite:

How big is the antenna?  How far do you need to broadcast and what is your bandwidth, power, and s/n?  Is it directional?  If so, how do you maintain attitude* (or do you not even choose the direction of broadcast)?

How much power does it take to produce the above (I'll assume that other power requirements are *small*).

How much efficiency does your output amplifier, your power supply, and your solar cell have?  What are you doing with the waste heat? (i.e. how big are your radiators?)

* if you need to maintain attitude, don't count on any of the "other" requirements being *small*.  If you don't, remember that the ground is several hundred km away, and you aren't going to be talking to anything that isn't in a nearby orbit.  What is the antenna used to communicate with, anyway?

[Kryten]

Why bother when kicksats already exist?

[OrbitalBuzzsaw]

 

4 minutes ago, Kryten said:

Why bother when kicksats already exist?

Say what now?

[Kryten]

1 minute ago, OrbitalBuzzsaw said:

Say what now?

https://www.kickstarter.com/projects/zacinaction/kicksat-your-personal-spacecraft-in-space/description

It's not just a kickstarter, they sent up a carrier and over a hundred of these things in 2014. The deployment mechanism failed, but there's a reflight set for this year.

[KAL 9000]

26 minutes ago, wumpus said:

The Devils in the details.  The obvious details from someone who has never built a [non-KSP] satellite:

How big is the antenna?  How far do you need to broadcast and what is your bandwidth, power, and s/n?  Is it directional?  If so, how do you maintain attitude* (or do you not even choose the direction of broadcast)?

How much power does it take to produce the above (I'll assume that other power requirements are *small*).

How much efficiency does your output amplifier, your power supply, and your solar cell have?  What are you doing with the waste heat? (i.e. how big are your radiators?)

* if you need to maintain attitude, don't count on any of the "other" requirements being *small*.  If you don't, remember that the ground is several hundred km away, and you aren't going to be talking to anything that isn't in a nearby orbit.  What is the antenna used to communicate with, anyway?

It's going to be spin-stabilized. No reaction wheels or RCS, but the deployment mechanism will spin it up. Well, I'm guessing that an antenna could be miniaturized to maybe 1 cm by 1 cm by 3 cm? Power, probably ~1.5-3W. A small battery provides power in the night, and the solar panel has a passive radiator on the non-photovoltaic side.

The antenna is omnidirectional, and would broadcast on any frequency that's accessible and not already taken. Probably not a lot of bandwidth, but you could probably get an image in a couple of seconds and basic data/readings in less than a second.

Edited April 19, 2016 by KAL 9000

[PB666]

3 hours ago, Kryten said:

https://www.kickstarter.com/projects/zacinaction/kicksat-your-personal-spacecraft-in-space/description

It's not just a kickstarter, they sent up a carrier and over a hundred of these things in 2014. The deployment mechanism failed, but there's a reflight set for this year.

Not sure if I want to put my name on 100s of pieces of spacejunk. 

[fredinno]

6 hours ago, KAL 9000 said:

If you haven't already, see the Femtosats thread where I came up with the idea. This thread is for you guys to offer suggestions and criticisms for the idea and its details, as well as to comment on my proposal in general.

The SDUTTsat is a tiny satellite. (SDUTTsat stands for Super-Duper-Ultra-Teensy-Tiny-satellite) It's really just a computer chip with a tiny solar panel for power and a small antenna for communications. It could carry small sensors, more antennas to make it a tiny communications satellite, or anything really within the size limit. A Cubesat could release it, or it could be mounted on a tiny rack with springs on an upper stage, to be jettisoned once it reaches orbit.

What happens if it gets hit by a speck of Space dust?

Also, it's almost certainly useless at our tech level. A computer chip by itself does not have enough capability to do anything major of note other than fly around and send a signal every so often, especially space-hardened computer chips.

[Kryten]

58 minutes ago, PB666 said:

Not sure if I want to put my name on 100s of pieces of spacejunk. 

They're deployed to ISS orbit, and have high surface-to-weight ratio, so they're very short lived. Worst case is estimated at six weeks.

Edited April 20, 2016 by Kryten

[RainDreamer]

Well, aside from what has been mentioned, if there's one thing I learned from people dealing with space stuff, is that they have awesome acronyms naming sense. SDUTT is not going to cut it, I am afraid.

[kerbiloid]

13 hours ago, KAL 9000 said:

A Cubesat could release it, or it could be mounted on a tiny rack with springs on an upper stage, to be jettisoned once it reaches orbit.

Why that rack? It can just spray them into orbit through a tube. Spore-sat.

[p1t1o]

I'd rather 1 mega-sat than a cloud of tiny ones

[KAL 9000]

10 hours ago, RainDreamer said:

Well, aside from what has been mentioned, if there's one thing I learned from people dealing with space stuff, is that they have awesome acronyms naming sense. SDUTT is not going to cut it, I am afraid.

How about KERBAL? racK-stored-EaRth-orBiting-smALl-satellite.

[PB666]

Why not do one of something that would survive,

Put the satellite into an aluminum polyhedron and put solar panels on each side.

Put a small cannae drive out of one face (-Y), 4 photon thrusters oriented on the XZ axis sun orient to the +Y Orient it to the sun, every time it comes around the earth have it pulse the cannae drive. See if you can kick it from earths orbit. lol. That would make communicating with it a whole lot easier. lol. What you need in a situation like this is a burst communicator, something that puts out alot of power for a breif period of time. Use one face (the face that points at the earth will it is receding from the earth and blast the communicatoy. 

 

[fredinno]

3 hours ago, PB666 said:

small cannae drive out of one face

And thus you destroyed any sense of this proposal being taken seriously.

[wumpus]

20 hours ago, KAL 9000 said:

It's going to be spin-stabilized. No reaction wheels or RCS, but the deployment mechanism will spin it up. Well, I'm guessing that an antenna could be miniaturized to maybe 1 cm by 1 cm by 3 cm? Power, probably ~1.5-3W. A small battery provides power in the night, and the solar panel has a passive radiator on the non-photovoltaic side.

The antenna is omnidirectional, and would broadcast on any frequency that's accessible and not already taken. Probably not a lot of bandwidth, but you could probably get an image in a couple of seconds and basic data/readings in less than a second.

After a little googling it looks like you could probably get low dialup speeds (maybe *early* dialup speeds, like 110 baud).   Hopefully you wouldn't need fancy tracking antennas on the ground side (without which you might wind up on the low side).  Note that it will only be overhead of any one location for 1/500th or so of an orbit and depending on the inclination will go multiple orbits per time it goes overhead (and note that 1/500th assumes it is passing *directly* overhead.  Not the typical orbit.)

What would you be measuring, such that it could send everything back over the course of 10 or so seconds every few orbits?  Back in the day, I thought that some sort of relayer/chatterer (relay everything transmitted for an orbit) would be cool, but had no idea how limited it would be.  Still might be fun for a femtosat, but largely impractical.  I also suspect you would need some custom protocol/ECC/modulation so it wouldn't be just a "tune in and listen" for HAMs to hear, but maybe software defined radio (especially through your GPU) might change that.

What advantage would spin stablization have?  It makes sense during launch, but there doesn't appear for any need for this thing to be stable.  On the other hand if spinning it needs solar panels in all directions (since it doesn't know where the Sun is) and radiator panels won't work (the Sun will likely shine on them as not, defeating the purpose).  Anyone know if you had a larger solar panel "sticking out" and a larger radiator at right angles, would it ever (i.e. before it burns up) orient itself with the solar panels to the sun (due to the pressure of the light spinning it towards that direction)?  If you could (slightly) angle any of the panels, would it help?  Note that the Sun's position + clock + software should tell you the location to point the antenna, so it might be worth having something that can rotate and have directional gain, but I suspect that stiction would probably send you back to "just make it even more simple".

[Kryten]

49 minutes ago, fredinno said:

And thus you destroyed any sense of this proposal being taken seriously.

Just replace it with a Dean drive then.

[KAL 9000]

1 hour ago, wumpus said:

After a little googling it looks like you could probably get low dialup speeds (maybe *early* dialup speeds, like 110 baud).   Hopefully you wouldn't need fancy tracking antennas on the ground side (without which you might wind up on the low side).  Note that it will only be overhead of any one location for 1/500th or so of an orbit and depending on the inclination will go multiple orbits per time it goes overhead (and note that 1/500th assumes it is passing *directly* overhead.  Not the typical orbit.)

What would you be measuring, such that it could send everything back over the course of 10 or so seconds every few orbits?  Back in the day, I thought that some sort of relayer/chatterer (relay everything transmitted for an orbit) would be cool, but had no idea how limited it would be.  Still might be fun for a femtosat, but largely impractical.  I also suspect you would need some custom protocol/ECC/modulation so it wouldn't be just a "tune in and listen" for HAMs to hear, but maybe software defined radio (especially through your GPU) might change that.

What advantage would spin stablization have?  It makes sense during launch, but there doesn't appear for any need for this thing to be stable.  On the other hand if spinning it needs solar panels in all directions (since it doesn't know where the Sun is) and radiator panels won't work (the Sun will likely shine on them as not, defeating the purpose).  Anyone know if you had a larger solar panel "sticking out" and a larger radiator at right angles, would it ever (i.e. before it burns up) orient itself with the solar panels to the sun (due to the pressure of the light spinning it towards that direction)?  If you could (slightly) angle any of the panels, would it help?  Note that the Sun's position + clock + software should tell you the location to point the antenna, so it might be worth having something that can rotate and have directional gain, but I suspect that stiction would probably send you back to "just make it even more simple".

Good points! It would spin once every second, so the panel would see the sun for 0.5 seconds at a time, followed by 0.5 seconds of darkness. Hopefully, it wouldn't overheat completely during the day, because the radiator would get rid of the excess heat at night.

[PB666]

3 hours ago, fredinno said:

And thus you destroyed any sense of this proposal being taken seriously.

As opposed to dumping 100 pcbs into short lived orbit?

Why not, if you are going to shove something up that is going to expire. Lets show the space community what kerbal is about, taking unnecessary risks for the sake of  fireballing things up. Lets see if we can get a satellite to do a flyover the curiosity rover and drop a spare tire down for it, or maybe do a crashing descent onto miemos.