[0.19.1] "Stargazer" Segmented Orbital Antenna Array

[Temstar]

Weather you're doing radio interferometry, communication with spacecraft far far away or build sinister superweapons, you need some sort of large antenna.

The problem with large monolithic antenna is that they are difficult to design and even more difficult to install onto a working platform, either on the ground or in space. Aperture synthesis technology allows multiple small antennas to be combined into one large antenna, thus allowing large synthetic aperture antenna to be constructed in parts. Having attempted and failed to build a large one piece parabolic dish I decided to down this path.

First to launch is the framework of the new array, consisting of a frame to hold 13 independent antennas which will be installed later, as well as central section with large RCS tank, orbital manoeuvring engines and fuel, a lander can in case it needs to be manned and two docked RCS tugs which will be used for the construction of the array.

Array frame deployed on orbit.

Next to launch is the Antenna Carrier - a small robotic spacecraft carrying a single antenna to be installed on the frame.

Antenna installed. Installation of the antenna is relatively simple as the antenna is already orientated the right way with the base end forward. This first antenna is installed on the centre spot on the frame.

With the antenna installed, the carrier can now be deorbited.

But installing antenna one launch at a time will take too long. To facilitate rapid construction of the array I've designed a Heavy Antenna Carrier capable of launching four antenna to the array in one go

Heavy Antenna Carrier docked with the rear docking port of the array. We can now go about installing the antennas onto the frame.

Installing each antenna onto the frame is a little bit complicated. Since the Heavy Antenna Carrier carries each antenna with the front end docked to the ship both RCS tugs will be required to install an antenna. Each of those RCS tugs are equipped with 100L RCS tank, big stack battery, ASAS, four RCS quads and one large docking port on one end and one small one on the other end. The steps for assembling the antennas are:

1. Undock one RCS tug and dock with the rear end of an antenna with the large docking port

2. Undock the front of the antenna from the carrier

3. Manoeuvre the antenna + rug away from the carrier

4. Undock the other RCS tug and dock to the front end of the antenna with the small docking port

5. Undock the RCS tug docked to the rear of the antenna to clear that docking port

6. Manoeuvre the RCS tug still attached to the antenna to attach the antenna onto the array's frame, ASAS would be very useful here.

7. Attach the RCS floating around to the next antenna to be moved, refuel both RCS tugs.

Once all four antennas have been assembled onto the framework the antenna carrier can then be undocked and deorbited. Before you do you'll probably want to refuel the array and the RCS tugs with any left over fuel in the carrier.

The array, now dubbed "Stargazer" in various stags of assembly.

The Stargazer Array, fully assembled and operational in LKO.

Craft files:

Stargazer Array(frame): http://www./download.php?bnmcay52wm6p4k1

Antenna Carrier(x1): http://www./download.php?1t4x8cjjkqaiziu

Large Antenna Carrier(x4): http://www./download.php?do7h5u4sk1bv940

[Tada]

Well... I can see about 48 hours of siting in front of computer in future:

1. Building the whole thing in orbit above Kerbin (And then pushing it into higher orbit)

2. Building another one and getting it to Laythe - what is better idea: building the whole thing above Kerbin and then pushing it to Laythe or getting the frame to Laythe and then the antenas and building it there? I think that moving the whole thing would be more efficient, right?

It´s gonna be a long mission

[Temstar]

I say move the whole thing assembled to Laythe. I think the whole thing is under 50 tons and with that rear docking port there it shouldn't be too hard to come up with a nuclear tug for it.

A lot of docking is required to assemble it though, you're going to be either pretty good at docking to be able to put it together, or you will become very good at docking after you put one together.

[Maxthrust]

That is simply amazing...one of the coolest things I've seen so far.

[Spanier]

Nice work as usual

But assembly gets screwed up as soon as we get aerodynamics

[Tada]

50tons is ok, that is well within capability of mothership... To be sure I´ll pack some extra fuel. Aerobraking that thing around Jool will be spectacular...

And as far as docking goes - I´ve become pretty good at it pretty quickly. Or maybe I´ll give that as a mission to othere member of my crew

Edit: Just watching it and letting the thoughts kinda float I´ve came up with and idea - that one day, when (godforbids!) re-entry heat is added we might use similar constructions attached to a nose of ship act as an aero-braking shield for our journeys

Edited May 5, 2013 by Tada

[Temstar]

For those who can't be bothered to put a Stargazer array together in orbit I present: Stargazer Array Prefab - a single piece fully assembled Stargazer with a Zenith VII launch vehicle capable of putting it in LKO:

Stargazer Array Prefab in the VAB, it's pretty big at 592 parts.

Lift off!

Gravity turn, it's pretty wobbly but rest assured I've test flight it and its pretty controllable and will stay together.

Last pair of booster jettisoned

Climbing to orbit on core stage

Core stage jettison. The Zenith VII can comfortably put the array into a 75km x 75km orbit. Alternatively you can aim for a 100km orbit and it will insert it to near that orbit and you can just finish the orbit with the array's orbital manoeuvring engines while the core stage can deorbit itself with its RCS thrusters.

Stargazer Array circularising the orbit with its orbital manoeuvring engines

Orbit insertion complete.

Craft file:

http://www./download.php?0anmecnbao5b65w

[Peekie30]

the dish-deliver probe thingy looks like a TIE-fighter

[Tada]

Wow... I guess I skip lunch today and go try this!

[Tristavius]

Y'know, I saw the first screenshot and thought 'hmmm, some antenna mod or something'. Then I saw the next one and realized what they were made of and how big they were and man, that is awesome! I may have to build something similar. Though I think it may have to be launched in one piece... I was wondering all the way through why you didn't!

[Tada]

My impressions:

Launching was pretty easy, but I did mistake somwhere and I had to use some of the array fuel to get circuralized. I´ve tried undocking and docking back with one satelite dish - it was hard... I´m glad for that pre-fab But possibility of replacing damaged segments its great!

Only two questins are remaining for me - will be my mothership powerful (have enought dV) to push it to Laythe? And what is the best placement of arrays for Kerbin-Laythe com-link?

[automcdonough]

i like it

[3_bit]

Inset Doctor Evil Laser meme picture here.

I'm sure you could start fires from space if all those arrays were refracting adjustable mirrors.