Deep water kethan mining

[seanth]

Plugins: Kerbal attachment system, Kethane Pack

After a bit of experimentation, I've successfully managed to mine kethane in just over 300m of water. The rig I built should allow me to reach a depth of 600m, but this was just a test. I know that there are submarine parts one can get through addons, but if you attach to a submarine using a docking port, everything behaves like a part of the sub, which is not what the exercise was about. I really wanted a floating refinery that tanker could dock with and fill up on kethane.

Starting with one of the orange tanks, I attached two of the small kethan drills, and a series of KAS winches. At the top of the winches is the floating "refinery."

Surface docking station and the "waterstrider" transport used to deliver the kethane rig

A top-down view of the surface docking station. Far under water (~300m) can be seen the orange tank.

Despite the dark, you can see the kethane plume coming up from the mining activity, as well as one of the KAS winches.

The single largest problem in the whole design was transporting the whole thing off shore. I have a series of "water strider" style transporters for ocean transport, but this thing was slightly wider than most other things I have transported (like a terrestrial kethane mining and refining setup for use on a continent across the ocean). Once in place, it works fine, but setting the rig up is difficult because as the tanks sinks, the center of balance for the entire craft moves. In the end there is a craft that is over 300m in length, making it very hard to click on any desired part. I found the best way to deploy the "drill head" (the orange tank and the kethane drills) is to extend the winch closest to the surface and work my way down the chain.

While this was a successful test, there are still aspects that require refinement. Particularly the transport ship. The ship, without cargo, can average 60m/s on water. With a moderate load, 40m/s. This underwater mining setup had it's weight distributed in such an odd way that the whole craft nearly turtled. A bit more work and I think it should be possible to average speeds of at least 20m/s.

[M4ck]

Interesting. How did you get the drill to sink? Does it simply go down if you extend the cable instead of floating right beside your vessel? I haven't tried it yet, but I thought that the "water" is very, very dense and nothing sinks in it.

Edited September 9, 2013 by M4ck

[Synapse]

The best part is the drop shadow on your screenshots - how the hell did you manaage that?

[seanth]

Interesting. How did you get the drill to sink? Does it simply go down if you extend the cable instead of floating right beside your vessel? I haven't tried it yet, but I thought that the "water" is very, very dense and nothing sinks in it.

The orange tanks will sink in water (as will the largest filled kethane tank). The trick is to attach items to an orange tank, but not so many items that the tank becomes boyant again. In my experiments, I found that an orange tank with full oxidizer and 1000L of liquid fuel will sink with two small kethane drills and some attached KAS winches. Since the orange tank is attached to things at the surface, you can pump fuel around and change the buoyancy. With zero L of liquid fuel, the orange tank and drills will start ascending from the bottom.

[GeneralMDBK]

Nice Rig, I don't know when I'd use it but it's a great design.

[seanth]

An update:

To reach depths greater than ~350m, I needed to refine the design a bit and use more weight (two orange tanks). The transport of the entire mining rig is proving difficult and might end up requiring a two step process: A ship to deliver the mining rig to the spot in the ocean, and a second ship designed to transfer the liquid fuel and oxidizer into it. Right now, raising a two tank mining rig into one of my transports using winches creates a shifting center of balance. Which is fine on land, but results in near disasters at sea. It also means that top speeds are limited to under 5m/s. One possibility is to make the mining rig more modular. This would allow it to be more easily transported in pieces to other planets.

Maybe something like:

Orange tank+2 small drills+docking port|docking port+5 winches+docking port|docking port+orange tank+5 winches+docking port|docking port+surface buoy

That way the central port+tank+winches+port are modular, letting you have as many or as few as you need, and something that could be assembled on the surface of a planet/moon with the help of a small tugboat.

Anyway, here's the KSS Tippy Canoe (the transport ship) docked with the kethane mining rig (Deep Six). The drills are in 600m of water and successfully extracting the kethane. You can just make out the drill activity in the lower center of the image.

And in this next image, a test kethane transporter is docked with the KSS Tippy Canoe and is being loaded with kethane. The initial plan was to dock the tanker directly to the mining surface buoy, but a docking bug kept me from from undocking the Tippy Canoe (docking the tanker ship to the Tippy Canoe "fixed" the bug, but since I was already docked, why bother undocking).

I'm worried that the kethane tanker design is just too big for the amount of kethane it can hold (a maximum of 192,000 liters). The plan is to completely fill the tanker and then see how it handles and what it's maximum speed is in a destructive test. I have left KSP running for 24hrs to allow the tanker to load, which is approximately 6.5 hrs of in game time. I'm assuming the lag is due to the three craft (mining rig, Tippy Canoe, and tanker) all docked together and making a pretty giant craft (remember that the drills are 600m away from the tanker). Anyway, it's paint drying, so I just let it run. I'd time warp things, but I'm afraid what the full tanker would do when suddenly do when exposed to 1x physics.

On a somewhat related note: do the oceans have currents? I've noticed that the ships are drifting over time, and that there is a bow in the 600m long cable as it runs from the surface down to the bottom. I suspect what I'm seeing is an effect of the physics engine sort-of-kind-of changing ship positions in water relative to the rotation of the planet. A coriolis effect, of sorts.

Edited September 13, 2013 by seanth

[Geschosskopf]

Wow, that's thinking outside the box! I've been wondering how to exploit offshore Kethane myself and had never thought of sinking the drills. I was considering tweaking the drill parts so they'd extend that deep.

FWIW, I find that the Hooligan submarine mod causes more problems than it solves for such applications. Instead of just adding some parts that work underwater, it changes how buoyancy works across the board, affecting ALL parts whether stock or mod. When using the mod, pretty much everything (including Kerbals) sinks like a stone unless you attach the submarine parts to it. The submarine parts are actually controllable floats, not ballast tanks. This puts a real damper on making floating platforms. And the other side of the coin is that the mod imposes a crush depth of 600m. Anything going deeper than that instantly explodes, which really limits where you can send submarine drills.

[M4ck]

FWIW, I find that the Hooligan submarine mod causes more problems than it solves for such applications. Instead of just adding some parts that work underwater, it changes how buoyancy works across the board, affecting ALL parts whether stock or mod. When using the mod, pretty much everything (including Kerbals) sinks like a stone unless you attach the submarine parts to it.

The first thing I usually do with any mod I install is looking into the config files. In this case, there is THIS:

// Replace the stock KSP buoyancy from all other non-ballast parts?  This should improve realism
// 0 for do not remove buoyancy from other vessel parts, 1 for yes
clearStockBuoyancy = 1

So change that to 0 and do whatever you want. I haven't tried it yet, I think the drill would try to float up without this enabled, but anything supposed to float would definitely float. Other than that, you can try to hold the drills attached to the bottom with KAS hooks.

[Geschosskopf]

So change that to 0 and do whatever you want. I haven't tried it yet, I think the drill would try to float up without this enabled, but anything supposed to float would definitely float. Other than that, you can try to hold the drills attached to the bottom with KAS hooks.

If you do this, you return to stock buoyancy and everything will float. The Hooligan submarine mod is essentially an underwater version of his previous airship mod. The airship mod relies on everything in the air tending to fall to the ground due to gravity, and the balloons apply an upwards force to oppose gravity. Same thing with the submarine mod. The mod makes everything sink but the submarine parts are analogous to the balloons in applying an upwards force opposed to gravity. That's doable if you want, but you have to remember that when using the mod's buoyancy, nothing can go below 600m.

So it seems to me the easiest thing all around is to keep the drills on the surface and do whatever you need to so they can reach down to the ocean floor from the surface.

[M4ck]

I was thinking about something more like having an assembly of surface storage/KAS/drill unit/KAS/ballast with KAS hooks.

First, the ballast with hooks would be lowered all the way to the ocean's bottom. The hooks would then attach to the bottom. After that, the upper KAS would be set to "release" mode and the lower one retracted, which should pull the drills all the way down without moving either the anchor or the surface module.

It would be a bit more complicated than what's used currently, but you would be assured the drills stay where you want them, and there would be no need to care about all those jumbo tanks.

[seanth]

I was thinking about something more like having an assembly of surface storage/KAS/drill unit/KAS/ballast with KAS hooks.

First, the ballast with hooks would be lowered all the way to the ocean's bottom. The hooks would then attach to the bottom. After that, the upper KAS would be set to "release" mode and the lower one retracted, which should pull the drills all the way down without moving either the anchor or the surface module.

It would be a bit more complicated than what's used currently, but you would be assured the drills stay where you want them, and there would be no need to care about all those jumbo tanks.

I like your idea of using the hooks to anchor the drills. I think, though, you'd need to make custom ballast parts for what you are describing to work. As far as I know, the only parts (other than submarine parts) that will sink are the big orange fuel tanks, and the largest kethane tank full of kethane. I went with the orange tanks simply for ease of design. However, now that I can harvest kethane, I can make a kethane-tank version of the mining rig.

I'd really love to see other people's designs if they try something similar

[Captain Sierra]

one thing you could do is make a dead weight part by modding a stock config to make basically a lead weight that would make a kethane wellhead sink. You use the wieght to get it down, then you decouple the weight after anchoring to the seafloor with KAS. The trick is getting the drill down. Once down, a few grappling hooks will hold it there. My technique is get it down, anchor it, then get rid of the counterweight. Use the winches holding it down to let it slowly up and anchor it to the topside platform. Then drag it back down and commence drilling.

A note: My KAS winches are modified to be 200m long so that makes this easier in deep water.

[Geschosskopf]

one thing you could do is make a dead weight part by modding a stock config to make basically a lead weight that would make a kethane wellhead sink

Check the "To the Bottom of the Ocean" thread here from a few weeks back. To sink something with stock buoyancy, you need either rockets continually pushing it down or totally insane modded part densities (up there with neutronium), which makes it rather difficult to move such parts off-planet. This is all an offshoot of Kerbin being a toy-sized planet with Earth-like gravity. So as the OP said, the more parts you add, the more tendency there is for the thing to float, because even solid I-beams float in Kerbin's oceans (without the submarine mod).

Exploiting Kethane on Kerbin or anywhere else within the Kerbin system isn't cost-effective. Kethane is only worth messing with at other planets. So, offshore drilling is really only worth doing at Laythe or Eve, and even there it depends on where the Kethane is relative to the land. This means that unless you can get the offshore drilling assembly to these places, it's not worth doing, and this argues against using ultra-heavy parts. OTOH, you can use the submarine mod, but then you have to accept that everything deeper than 600m is forever out of reach.

[seanth]

Check the "To the Bottom of the Ocean" thread here from a few weeks back. To sink something with stock buoyancy, you need either rockets continually pushing it down or totally insane modded part densities

I'm not sure that is completely true. I'm not using any modified parts to get the kethane drills to sink. Only the ones provided by Squad. Now, I did modify the winches I am using to be 100m vs 50m, but that isn't messing with part masses. I'm happy to post images and/or share the .craft file for those interested.

Exploiting Kethane on Kerbin or anywhere else within the Kerbin system isn't cost-effective. Kethane is only worth messing with at other planets.

The rules of a game I'm getting ready for are that I allow myself a certain fixed amount of fuel at the start of a game. After that point, I start using only a set of custom parts, which are just the Squad parts but without any fuel. I will _have_ to mine kethane on Kerbin in order to do anything. It also means I'll have to design rockets in such a way that I'll be able to fuel them from tanker trucks or something.

It's certainly not as cost effective as free fuel, but I'm curious how hard it is.

That plus using Deadly Reentry is Ironman/Impossible mode, I think.