IRSU - how do you handle fuel transfers on the surface?

[Xavven]

All my IRSU logistics designs to date have involved landing a whole refinery with drills, mining and refining on the surface, then returning everything to orbit and docking with the craft to be refueled. This works on low gravity bodies, and I like its simplicity of implementation.

But on heavier bodies with higher dV requirements, hauling the drills and refinery to orbit and back (and empty ore tanks) eats into my total fuel yield.

So I've been considering having a permanently grounded refinery and a separate fuel delivery lander, but my major logistical hurdle is the fuel transfer on the ground. Landing precisely on a docking port is quite tricky and maybe a fun challenge, but fuel-consuming, so I don't want to do that at all. It is within my abilities to land very close by (within crane range) and have a crane arm connect, but I'm concerned about dealing with uneven ground and therefore having to have a robotic arm or crane that articulates in 5 axes, potentially with a counterweight, and that can fold up nicely into a fairing. Doable, but I feel like it's maybe overly complex? I've thought of having a wheeled fuel-truck rover act as a middleman between the refinery and the lander, but that has downsides too, and the same issue of having to line up docking ports on the surface at predefined heights and angles. Maybe that approach is more complex, actually?

So I'm looking for suggestions. How have you grappled with this problem?

[bigcalm]

Question - with or without mods?

But yes, imagine if the Kerbals invented such a ground-breaking concept such as a hosepipe.  What wonderous science that would be!

Without mods:  Maybe a rover with a Klaw on the front.  Yeah, it's likely quite Krakeny, but autosave before doing any "docking" and you should be ok.

With mods:  KAS gives you hosepipes (some faffing required), MKS gives you a window that allows automatic transfer within 150 metres (but MKS also comes with lots of other complexity, like life support).

Edited May 16, 2022 by bigcalm

[Xavven]

16 minutes ago, bigcalm said:

Question - with or without mods?

But yes, imagine if the Kerbal's invented such a ground-breaking concept such as a hosepipe.  What wonderous science that would be!

Without mods:  Maybe a rover with a Klaw on the front.  Yeah, it's likely quite Krakeny, but autosave before doing any "docking" and you should be ok.

With mods:  KAS gives you hosepipes (some faffing required), MKS gives you a window that allows automatic transfer within 150 metres (but MKS also comes with lots of other complexity, like life support).

Ah, yes, good questions and I should have specified. I'm playing vanilla/no-mods and with the restricted fuel transfer rules on. Fuel cannot transfer through the klaw part with the restriction option enabled.  Yeah, I had immediately thought of KAS for hoses, and in my unmodded game tried to get an engineer to weld an External Fuel Duct pipe between two crafts, and found out the base game doesn't let me do that.

[TheFlyingKerman]

This

Spoiler

 

[jimmymcgoochie]

Stock KSP: attach the two vessels using a Klaw, engineer attached external fuel duct between the attached vessels, transfer fuel as normal. EVA construction only allows parts to be attached to a single vessel, I’d imagine to prevent convoluted part tree messiness, but once attached I see no reason why you couldn’t attach a hose and transfer that way (note- not tested so I don’t know if this really works). Alternative option- docking ports attached to robotic pistons that can move the ports to the right height to dock on the surface (breaking ground DLC required).

Modded KSP: You could do the whole KIS/KAS hose thing, but instead I’d recommend Simple Logistics as it’s both faster and easier- just land near the refinery, request resources from the local logistics network and leave again without docking/attaching of any kind. It only works with vessels that are loaded though, so you’d need to babysit the mining operation if you wanted to do it in a modular way without attaching them together a la KIS/KAS, or use a more complex resource sharing mod e.g. MKS.

[Curveball Anders]

You don't need the ful KIS/KAS.

DMagic's EVA Fuel Transfer from the stash of small mods adds just the needed hose.

And with less clutter it's easier to use and less prone to odd behaviour.(IM(nv)HO).

 

[Xavven]

9 hours ago, TheFlyingKerman said:

This

  Hide contents

 

Aaaahh, brilliant and simple! Thank you!

 

6 hours ago, jimmymcgoochie said:

Stock KSP: attach the two vessels using a Klaw, engineer attached external fuel duct between the attached vessels, transfer fuel as normal. EVA construction only allows parts to be attached to a single vessel, I’d imagine to prevent convoluted part tree messiness, but once attached I see no reason why you couldn’t attach a hose and transfer that way (note- not tested so I don’t know if this really works). Alternative option- docking ports attached to robotic pistons that can move the ports to the right height to dock on the surface (breaking ground DLC required).

Damn, why didn't I think of that? A total workaround to the original issue I had-- not being able to weld a fuel duct to different craft. Just make them 1 craft, temporarily.  Thank you!

 

5 hours ago, Curveball Anders said:

DMagic's EVA Fuel Transfer from the stash of small mods adds just the needed hose.

 

Great! Just the kind of simple mod that removes the requirement to do a klaw workaround to get a hose connected, without adding other stuff I don't want to mod in. Thank you!

 

To all: what a wonderful community. In less than a day I got multiple great solutions. I'm excited to get my surface base going now! Another big thank you to everyone.

Edited May 17, 2022 by Xavven

[miklkit]

6 hours ago, jimmymcgoochie said:

Stock KSP: attach the two vessels using a Klaw, engineer attached external fuel duct between the attached vessels, transfer fuel as normal. EVA construction only allows parts to be attached to a single vessel, I’d imagine to prevent convoluted part tree messiness, but once attached I see no reason why you couldn’t attach a hose and transfer that way (note- not tested so I don’t know if this really works). Alternative option- docking ports attached to robotic pistons that can move the ports to the right height to dock on the surface (breaking ground DLC required).

Modded KSP: You could do the whole KIS/KAS hose thing, but instead I’d recommend Simple Logistics as it’s both faster and easier- just land near the refinery, request resources from the local logistics network and leave again without docking/attaching of any kind. It only works with vessels that are loaded though, so you’d need to babysit the mining operation if you wanted to do it in a modular way without attaching them together a la KIS/KAS, or use a more complex resource sharing mod e.g. MKS.

Yes.  I started out doing it that way with a klaw and hoses.  It worked but was clunky so I enabled fuel flow through the klaw.  Now I use KIS/KAS as it does not involve one craft crashing into another one.

[DeadJohn]

I used to do things the hard way: surface docking.

KAS mod fuel hoses came next. That eliminated all the wasted time needed to get perfect surface docking.

Now I just cheat things. I build my mining bases with a small permanently attached fuel tank and test that it actually works (enough EC, cooling, etc.). After that test I use Hyperedit to refill ships that land near the base. I'm playing a space game, not running a gas station simulator.