I want to see your Asteroid Tugs!

[Technical Ben]

I thought modular might be the best approach -- create a hub and add to it for larger class asteroids -- but on the way to high orbit with my first design, things seemed less than stable.

http://i2.photobucket.com/albums/y4/PokerTrann/KSP/ARM-beta_zps738910cf.png

So I decided to try a double-dock: this is a "wing" moving to mate with a center hub and another "wing"...

http://i2.photobucket.com/albums/y4/PokerTrann/KSP/ARM1_zps340f5ea2.png

I wasn't sure both would sync but after mating, I checked each dock and both offered 'undock' options so I'm thinking this is going to be pretty solid.

http://i2.photobucket.com/albums/y4/PokerTrann/KSP/ARM2_zps4d83aca4.png

Now... another pair of wings, a fuel top-off, and I'm off to find an E-class.

If docked correctly you can get multiple connections this way. I've made a few interplanetary tugs and ships like this. Though I go for central stacking now... might revisit side docking.

My next project involves 6-7 radially docked tanks... so will have to line those up really well!

[Trann]

If docked correctly you can get multiple connections this way. I've made a few interplanetary tugs and ships like this. Though I go for central stacking now... might revisit side docking.

My next project involves 6-7 radially docked tanks... so will have to line those up really well!

Yeah, I used the orange tank's rings as a guideline for the radial points when building the hub and wing ships. Looks like it worked out fine.

And that was my idea, too: if the first coupling aligned well, it should mean extended couplings could work. The current design was for something like this:

and I knew I'd not be able to dock the corners (red) so I'd decouple a row and re-dock as a row (green).

But now I'm wondering if I shouldn't have gone tighter...

(I'm using https://www.draw.io/ here; very useful quick app)

[Technical Ben]

No idea on the flex. Will need testing.

[TerLoki]

So far I've docked to two asteroids in career and captured one of them, the first conveniently already orbiting Kerbin.

That first rock was a class E behemoth in a highly eccentric orbit, so I sent this design, which I call Titan, to rendezvous with it.

With an orange tank plus an HGR service module worth of fuel feeding the highly efficient KW service propulsion engine this badboy has nearly 7 km/s of dV on its own. With the asteroid in tow that number is still an impressive... 40m/s. Yeah. I'm gonna need a bigger rocket.

But as luck would have it while the Titan was grabbing its quarry a little class B asteroid entered the system on an orbit that just barely escaped Kerbin's SoI. So I put together another tug with future exploration in mind: The Asteroid Docking Adapter, or "ADA".

After the debacle of my last asteroid mission I was hoping for 100 m/s max when docked, so imagine how surprised I was when I managed to not only capture this little asteroid, but completely circularize its orbit with around 300 units of fuel to spare! The ADA's engine module has since been jettisoned and it now serves as the docking port for a small orbital lab, the same kind I did my Mun and Minmus flybys with.

Edited April 11, 2014 by TerLoki

[Trann]

That's not a bad idea: the initial ARM component with a docking ring (sized appropriately) means you can line up fuel tugs and swap them out as you approach (think: cement trucks needed for a large pour).

[Elmetian]

Spotted an E type on my first 0.23.5 sandbox passing fortuitously close to Kerbin. Impatient as usual, so I sent Bill out there in a Mk2 Spider-class tug and some extra fuel on a very aggressive rendezvous. Fuel efficiency is for the weak and the faint of heart! Got there with 1 orange tankfull remaining, more than enough to do a scary aerocapture around Kerbin in 47 days time. However, I'm now regretting rushing out there without taking independent RCS tugs as I've seen others do...

... this thing wiggles like a pig that's just won a vodka jelly eating contest

[firegeek83]

My first string lineup.

Capture vehicle (ANCHOR)

Tug (left) and Alignment vehicle (right)

Alignment vehicle

[Matzilla]

Here's my contribution:

Very Mod heavy, uses at least KER, B9, RLA, NFPP, KW, and KAS

[Mekan1k]

Asteroid tug/retrevial vehicle, for my AAR

Propulsion:

4*mk1 differenetial sails

1* hyperdrive

[Othuyeg]

The part with the orange tanks is the tug. It has docking ports and can be extended by additional orange tanks.

[syfyguy64]

http://i.imgur.com/7Yqj7W2.jpg

The part with the orange tanks is the tug. It has docking ports and can be extended by additional orange tanks.

I don't know why, but this picture is as amazing as seeing the giant ring around the moon in Starship Troopers, probably because you can't see the entirety of the station.

also, the fact that it has a few things that make it lively, and not boring like this.

Edited April 14, 2014 by syfyguy64

[Vanamonde]

I use a two-step approach. First, a small ship

goes out to meet the roid in interplanetary space and guides it to aerobraking passes until it's in an eccentric orbit.

Then, my new big tug

meets the roid and adjusts the orbit to something more useful.

This tug, the M107 Shepherd, is the largest thing I've ever flown. It's 927 tons on the pad, which delivers the tug to orbit, nearly full of fuel, at 127 tons.

[Othuyeg]

I don't know why, but this picture is as amazing as seeing the giant ring around the moon in Starship Troopers, probably because you can't see the entirety of the station.

also, the fact that it has a few things that make it lively, and not boring like this.

Thank you. Here are the rest of my screenshots, if you are interested.

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[KerrMü]

The big goal is to put an E-class asteroid in Duna-orbit, for establishing a base. So I had to think quite big. and -okok- I intended practicing on a few smaller ones first, but the first asteroid ever appearing on the mapscreen was the following "light" E-class.

So here is my first approach to this problem:

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Now I will try it in my main-save. wish me luck

Edited April 15, 2014 by KerrMü

[DomDiaemus]

4 engines tug... 3 tugs holding a Class E

Establishing stable 500Km orbit

Latest version... 16 engines tug... hope this would speed up next Class E catch

Edited April 17, 2014 by DomDiaemus

[Taki117]

PFFT! Who needs the KLAW? I just use a couple of Tow Ropes! (KAS Winches) That's a D-class 'Roid by the way!

For the full mission report CLICK HERE!

[PidouX]

I'm also pulling those asteroids so far. But this is taking forever. I need to put that 2700t asteroid in a 90° orbit.

Any advice is welcome! 2500m/s to go....

Javascript is disabled. View full album

[Camaron]

OH NO! You pulled into LKO FIRST? Good luck leveling it out now, that's best done as far out as possible where speeds are slow and can be easily manipulated. If you're determined to level it from LKO, its just gonna take a while. and probably additional launches for fresh tugs. Best of luck.

[PidouX]

Yes I see the problem. Things started to get out of control too early. It's easier to catch a new asteroid

[Camaron]

This post hasn't seen a good new tug in a while.

Here's my Ion Tug, tossing a Class A into a perfect equatorial 1M km orbit around Mun.

Edited May 1, 2014 by Camaron

[RocketPilot573]

UISS Viper, modified with an additional fuel tank and tow bar.

[Zaryulenko]

Machenko! (the big one attached) "When everything else fails there's always a last option GO BIG OR GO HOME"

The Machenko Tug system was made as an Emergency purpose mover to prevent an asteroid from impact / Escape, This should only be used in emergency only

[John FX]

After seeing these designs I`m off to redesign my pusher as a puller.

Cool thread. Good to share designs. I`ll post mine when I`ve done it.

[Rune]

I'm also pulling those asteroids so far. But this is taking forever. I need to put that 2700t asteroid in a 90° orbit.

Any advice is welcome! 2500m/s to go....

http://imgur.com/a/8qP2A

Where and how you catch an asteroid is crucial, and fore planning is the key. By now when I catch asteroids its always in solar orbit, so even though the tug has to do upwards of 1km/s to match velocities out there in the black where the redenzvous indicator is pretty much worthless, I can afterwards nudge the asteroid to literally any insertion orbit I want for less than 50m/s, including choosing prograde/retrograde orbits. Two important things there: 1- get an aerobrake that just captures you but leaves you a high apoapsis, and 2- Make sure one of your nodes is close to apoapsis. Again, after the aerocapture pass, you will be be to choose whatever inclination you desire for less than a hundred meters second with a high enough apoapsis, then it's a matter of slowly circularizing with aerobrake passes, and raise the periapsis to the desired altitude, which is the only big expenditure of delta-v, and can't be avoided.

Compare that budget of ~500m/s for all the maneuvers with the asteroid attached to what you are spending trying to brute-force it at low latitudes.

Rune. Science FTW!

[Camaron]

Very "solid" advice, Rune.

Funny how this thread goes dark for over a week, and then it just lights up again after I post my tiny ship dropping a wussy Class A around Mun.