Docking ports as decouplers

[The_Arcitect]

So:  this is how the challenge goes:

RULES:

1: NO: Cheats, Debug menu, and hyper edit.

2: NO: decoupler's, or Separator's!!  IF YOU WERE ALLOWED: THERE WOULD BE NO CALLENGE!

3:  A Saparator or decoupler is replaced with a docking port

4: SSTO's are allowed, as long as the crewed part is able to dock. (SSTO's will need to also releace a probe into orbit.)

Spoiler

EDIT #1: After looking at the response, there has been a reform to the rules.

EDIT #2: More detailed difficulties + reforms to rules

CHALLENGE:

Easy: Land a 50+ ton lander on the mun.

Medium: Land on duna with a 100+ ton lander. (Returns to kerbin crewed)

Hard:Land on tylo with a 50+ ton Lander. (Returns to kerbin crewed)

Extreme: Land on Eeloo with a 33+ lander (Returns to kerbin crewed)

Custom: I do NOT limit creativity, do as you want to.

 

 

HAVE FUN!!

 

Edited March 22, 2019 by The_Arcitect

[Barzon]

@The_Arcitect, might want to edit your spelling

Edited March 21, 2019 by Barzon Kerman

[The_Arcitect]

1 minute ago, Barzon Kerman said:

@The_Arcitect, might want to edit you're spelling

Where?

I figured it out.

Edited March 21, 2019 by The_Arcitect

[sevenperforce]

The regular docking port actually masses less than a decoupler of equivalent size, so......I actually do this pretty regularly.

[Superfluous J]

Players can set docking ports to be like decouplers. As in, you can enable staging and disable crossfeed.

So really this boils down to making sure you have them all set up correctly and figuring out a clever way to handle radial attachments.

[vyznev]

6 hours ago, 5thHorseman said:

Players can set docking ports to be like decouplers. As in, you can enable staging and disable crossfeed.

So really this boils down to making sure you have them all set up correctly and figuring out a clever way to handle radial attachments.

...which isn't particularly hard either, since there are plenty of lightweight structural parts (like cubic octagonal struts) that you can attach radially and then stick a docking port onto.

(Also, there are a bunch of other parts in KSP that can act as decouplers, including structural pylons and heat shields, but I assume (ab)using those would be against the spirit of the challenge at least. And of course there's always explosive decoupling.  )

[Superfluous J]

5 minutes ago, vyznev said:

...which isn't particularly hard either, since there are plenty of lightweight structural parts (like cubic octagonal struts) that you can attach radially and then stick a docking port onto.

Actually docking ports will attach radially as well. The trouble comes in that attaching something to the docking port "radially" (i.e. not using the nodes) won't allow you to decouple.

It's a pretty easy problem to solve in the VAB, but it sucks to discover it at Laythe...

Edited March 21, 2019 by 5thHorseman

[vyznev]

19 minutes ago, 5thHorseman said:

Actually docking ports will attach radially as well. The trouble comes in that attaching something to the docking port "radially" (i.e. not using the nodes) won't allow you to decouple.

True. I was thinking more about the case where you'd rather not keep the docking port after staging, so you'd want to attach it to your core stage via the top node.

Edited March 21, 2019 by vyznev

[GRS]

*Smiles Mother-Duck-erly*

I think Hard should be like Gilly or anything, Minmus should be easier than Mun.

Can't say will i do that, but Tylo sounds good.

[farmerben]

I've kinda been working on this anyway.  I'm trying to put together a Jool 5 which satisfies my sense of style which includes the desire to create no debris, and have everything I leave behind be a stable satellite or surface outpost with communication.  

Doing an Apollo style Tylo mission on a low mass budget is the biggest challenge.  It's possible to overcome Tylo just by adding more stuff.  But it would be really cool to do it with 3 small modules and a total mass less than 30 tons.  It doesn't seem impossible but it is a challenge, especially when we make no debris or crashed stages, and each stage needs a mass of electronics.

 

Spoiler

 

The brute force approach.  5 Rhino's can haul everything including a spare kitchen sink.  

The Nukes are docked to the sides, and intended for interplanetary pushing.  The core stage can land and takeoff from Tylo with or without Nuke stages attatched.  It is so powerful is simply doesn't matter.

 

 

 

 

[The_Arcitect]

Everyone:

The rules have been edited.

 

Enjoy!

[bayesian_acolyte]

Wouldn't SSTOs qualify for this? I built one for the Jool 5 including a Minmus landing that had no decouplers or separators. It also didn't have a docking port, but that doesn't seem to be required by the OP, and would be easy to add anyways. 

[vyznev]

2 hours ago, farmerben said:

Doing an Apollo style Tylo mission on a low mass budget is the biggest challenge.  It's possible to overcome Tylo just by adding more stuff.  But it would be really cool to do it with 3 small modules and a total mass less than 30 tons.  It doesn't seem impossible but it is a challenge, especially when we make no debris or crashed stages, and each stage needs a mass of electronics.

So build smaller. If I didn't screw up my delta-v calculation, this thing should be able to (barely) take off from Tylo into a low orbit:

Add one more fuel tank if you'd like a bit more margin. The Spark engine has plenty of thrust for it. Building the landing stage around this is left as an exercise. 

Edited March 21, 2019 by vyznev

[farmerben]

7 minutes ago, vyznev said:

So build smaller. This thing can (barely) take off from Tylo:

Add one more fuel tank if you'd like a bit more margin. The Spark engine has plenty of thrust for it. Building the landing stage around this is left as an exercise. 

That looks like a throw away.  The spirit of the challenge is that everything has a docking port, power generation, antennae, (probe core?) etc.  Nothing is a fully dead stage.  And if you think 3 small solar panels is enough you haven't gotten stuck with your back to the sun.

 

[vyznev]

18 minutes ago, farmerben said:

That looks like a throw away.  The spirit of the challenge is that everything has a docking port, power generation, antennae, (probe core?) etc.  Nothing is a fully dead stage.  And if you think 3 small solar panels is enough you haven't gotten stuck with your back to the sun.

As shown in the picture, it is indeed disposable, but a Jr size docking port would not significantly increase the mass. You could even refuel it and use it to land on Pol and Bop. With careful flying, it should even be able to land on Vall and return to orbit.

Or, alternatively, you could stick a probe core, a solar panel and an antenna onto it and leave it in orbit. Maybe put a thermometer there too, so it's technically a useful science satellite.

And yes, even one solar panel is plenty for a small science sat like that. The battery holds plenty of charge for the reaction wheel to turn the satellite around to face the Sun, and you can disable the battery before switching vessels to make sure that the probe core won't drain it. (KSP still lets you re-enable it later, even if the probe core has run out of power in the mean time.)

Edited March 21, 2019 by vyznev

[farmerben]

I think you're on the right track with using a single spark to takeoff from Tylo.  And it's not too difficult to single stage the landing with a single poodle, plus all the gear.  But, questions of style are at stake.  

Spoiler

Starting out at 103 tons, with a cheat to Tylo orbit.

 

These two boosters with two landers sail off.  Two boosters remain attatched to circularize at 20 km.  Everything is nearly full of fuel at this point, but I could have had 2000dV to get the rover to Tylo if necessary.  

There are lighter landers than a single vector that work.  But style is a concern.  This ship is about 22 tons empty.

 

The rover could one day orbit again, by the simple logic that landing on Tylo is harder than taking off  Or it might stay and refuel things that come to the surface.  

Getting to orbit on a single spark is easy.  But adding enough value that it is not debris is a little trickier.

 

So I went and landed the same ship on Vall that had taken off from Tylo.  There is enough dV to go to Bop or Poll as well.  

 

I didn't bring a Laythe Lander this time, or do the real interplanetary transfer.  All the individual parts of the Jool5 mission are straightforward to test.  But putting them all together is still a huge challenge.  Especially with the constraint of no debris.  

 

[Superfluous J]

On 3/20/2019 at 8:32 PM, The_Arcitect said:

Extreme: Land on Eeloo with a 25+ lander (Returns to kerbin)

25+ tons or crew?

[The_Arcitect]

20 hours ago, 5thHorseman said:

25+ tons or crew? 

It has to be over 25 tones and has to have crew.

(I will make it more clear.)