Relocating Chobe Mün Base - Help needed!

[DeepSpaceDutch]

So I created this purdy litle Mün base, named Chobe Base, as part of my larger Kerbin - Mun infrastructure (a few stations, bases and associated landers/shuttles).

After delivering two rovers I still had some fuel left in the robotic lander and whattayouknow, when I was crashing it I think I spotted the Neil Armstrong memorial. So later I send Jeb and Bill in my Mk2 Mun Return Lander to check things out.

Turns out the memorial is about 100km to the East of Chobe Mun Base. Time to relocate the base my first thought was! But there are some small complications, Chobe Mun Base is located on the bottom of a large crater. Earlier scout missions have shown that the rim is very steep and there are no driveable exits out of the crater.

Besides, driving 100km is gonna be a pain and the terrain to the West of Neil Armstrong Memorial is very rough. So it was quite quickly decided driving is not a viable option, so what then?

Only the oldest of the 3 base components has a docking port on top (I never imagined a relocation), and I don't want to make a very complicated contraption using the 2 smaller side docking ports. Also I have bad experiences with docking two ports at the same time.

So I decided on some kind of space barge. A large platform with one horizontally placed docking port. I would split the base into the 3 components. One component will drive onto the barge, dock so that it will stay in place and the barge will fly to the new location, unload and repeat.

Getting giddy with excitement I started prototyping and after a few iterations I had a platform-prototype that would not crumble under the weight of the heaviest of the components (the wheeled hab/fuel depot).

Of course it's still devoid of any engines or other gizmos, this is just to check the feasability and strength of the structure. Some extra images so you can see the details;

It could easily support the weight of the base component, but things went bad when I docked, as shown in the images below;

When it docks the base component's back end jumps up and when it goed down again it goes through the structure and freezes. When I go back to the Space Center and back to this craft the routine in the images above happens and everything ends in a fireball.

So is this solveable? Am I doing something wrong? When I was typing this it dawned on me that I may need to stiffen the structure around the barge's docking port, but is that gonne make a difference? Anybody?

PS: The only mods I use are MechJeb and the Lazor Dockingcam, I really don't want to start structural mods just yet.

[loknar]

Did you try turning off the :useHollywoodMovie-style_physics: option?

[el_coyoto]

I think building your barge out of many small panels is always going to cause you trouble because of the slightly wacky physics.

You may try to duplicate the part and modify its size so that you would only 2 or 3 of those to build your barge and make much less prone to spontaneous disassembly.

I see that some of your modules have as Sr docking port over them and docking port on their ends : would it be possible to design a lander/relocation module with enough ground clearance to let your one of your rover/station module drive beneath it and then dock the rover to the lander module?

It's basically your idea (flying to the NAM rather than driving), but with the lander above your station rather than under, thus avoiding the need to design a loading ramp.

[DeepSpaceDutch]

IYou may try to duplicate the part and modify its size so that you would only 2 or 3 of those to build your barge and make much less prone to spontaneous disassembly.

I'm sorry if I'm a bit thick, but with duplicating do you mean Left click+Alt? And how do you modidy the size? thanks dude!

I see that some of your modules have as Sr docking port over them and docking port on their ends : would it be possible to design a lander/relocation module with enough ground clearance to let your one of your rover/station module drive beneath it and then dock the rover to the lander module?

Yeah the problem is that on the Mun Base only one of the components has a Sr docking port on top, the light tower/node and the newer hab don't have it. So that kind of eliminates that possibility.

It's basically your idea (flying to the NAM rather than driving), but with the lander above your station rather than under, thus avoiding the need to design a loading ramp.

I've tried thinking of alternative ways, like connecting two identical rocket-packs to either side of the hab modules, but I'm afraid the middle sized docking ports are not strong enough and everything wil go wobbly and explody...

Edited August 9, 2013 by DeepSpaceDutch

[carr0tz]

Ok, being a long time forum lurker (hi), I like this project so much i decided to register for it

I do not know your view on mods, but with http://kerbalspaceprogram.com/0-18-2-kas-kerbal-attachment-system-v0-1/ you can use try tying the moonbase down to the platform. It is not perfect, but with the brakes on on the parts of the base and 4 to 6 cables holding the part down it is worth a shot.

[DeepSpaceDutch]

Ok, being a long time forum lurker (hi), I like this project so much i decided to register for it

Well I feel honoured good Sir!

I do not know your view on mods, but with http://kerbalspaceprogram.com/0-18-2-kas-kerbal-attachment-system-v0-1/ you can use try tying the moonbase down to the platform. It is not perfect, but with the brakes on on the parts of the base and 4 to 6 cables holding the part down it is worth a shot.

As I said in the OP I only use MechJeb and the Lazor Docking Cam, I've been thinking about KAS but I wan't to keep my craft as stock as possible to be honest. But maybe I should forgo that stance in this particular case. I do have a few questions as I have no experience with KAS what so ever;

- The Mun base is already where it is, there is no way I can add new (KAS) parts to them, is that a problem?

- I think my problem has to do with the physics the moment I dock, I have the feeling that when you dock and two craft essentially become one craft there is some sort of physics reset or re-callibration that in this case makes everything go boom. Is connecting two craft with KAS the same as docking? Or is it an entire different animal?

Thanks carr0tz!

[zarakon]

Collision detection doesn't work properly between parts of a single craft. That's why when people use wheels to make stock rotors, the spinning part and the main craft have to be separated.

As soon as you dock, the barge and your base module become one craft, so collision stops working.

See if you can come up with some way to secure it to the barge that doesn't require docking. Maybe try to use lander legs as clamps

[DeepSpaceDutch]

Maybe try to use lander legs as clamps

^THIS

Thank you zarakon, never thought of this one. If this doesn't work the KAS idea maybe a good alternative.

Will post updates and pictures in case of succes, or in utter and complete failure

[Tw1]

I also recommend the KAS cables, but I suggest adding a pair of poles to the side, and having cables hold it up. Plug them in in undocked mode, leaving the winch in release mode. Then dock, and pull the cables tight.

Better bring lots of SAS, as the modules probably won't be right in the center.

Base relocation is quite an adventure, I wish you and your kerbals good luck!

[DeepSpaceDutch]

and having cables hold it up.

To be clear; using cables to hold the Hab module up so that it doesn't collide with the structure when docking, correct?

Better bring lots of SAS, as the modules probably won't be right in the center.

Don't worry, was already planning on SAS'sing the bejezus out of that thing

I wish you and your kerbals good luck!

Thanks, I think we're gonna need a lot of that, luck....

PS: So I don't need to modify the crafts already on the Mun in order to use KAS, correct?

[carr0tz]

No, KAS has attachable connection ports which your kerbals can place on pieces or you can attach a magnet to the cable which can connect to most pieces as well.

[el_coyoto]

I'm sorry if I'm a bit thick, but with duplicating do you mean Left click+Alt? And how do you modidy the size? thanks dude!

Yeah the problem is that on the Mun Base only one of the components has a Sr docking port on top, the light tower/node and the newer hab don't have it. So that kind of eliminates that possibility.

I've tried thinking of alternative ways, like connecting two identical rocket-packs to either side of the hab modules, but I'm afraid the middle sized docking ports are not strong enough and everything wil go wobbly and explody...

Oops, I wasn't clear enough : I meant modding your game by duplicating and altering the files that describe the structural panel part to make it bigger.

I never did it myself, so it's not a really good advice...

I've been thinking about this during the afternoon, and it's true that it's hard to find a good "stock" solution to this problem. The "two identical rocket-packs to either side" solution could work even with a little bit of wobble, but would require you to be very careful with the thrust and the landing speed of this setup. Plus the right quantity of RCS/reaction wheels to account for any asymmetry in your base, so that would probably not be a very practical solution.

The people directing you to KAS have done a much better job than me.

The lifting operation should be interesting : will you post pictures of the relocation process?

Good luck!

[hugix]

Really...

Amsterdam...

...

[Crown]

Is the problem solved yet?

What if you just park the base in this transport platform and just hit the parking break? Requires some flying skills but I'm sure you can do it.

[DeepSpaceDutch]

No, KAS has attachable connection ports which your kerbals can place on pieces or you can attach a magnet to the cable which can connect to most pieces as well.

Magnets sound like it could help tying the modules down to the platform. If zarakon's idea of the lander legs is not sufficient I shall start looking at KAS.

Oops, I wasn't clear enough : I meant modding your game by duplicating and altering the files that describe the structural panel part to make it bigger.

I never did it myself, so it's not a really good advice...

Haha, I really don't have skill set to do such a thing

I really don't have the skillset to do just that, but thanks!

I've been thinking about this during the afternoon, and it's true that it's hard to find a good "stock" solution to this problem. The "two identical rocket-packs to either side" solution could work even with a little bit of wobble, but would require you to be very careful with the thrust and the landing speed of this setup. Plus the right quantity of RCS/reaction wheels to account for any asymmetry in your base, so that would probably not be a very practical solution.

I was thinking the same, also the first test would be on the Mun, so that's a no-go.

will you post pictures of the relocation process?

Good luck!

Thanks and absolutely!

Really...

Amsterdam...

...

Very informative and helpfull, you're a great contribution to the community, keep up the good work Sir!

Is the problem solved yet?

What if you just park the base in this transport platform and just hit the parking break? Requires some flying skills but I'm sure you can do it.

No not yet, haven't had the time until today. Hopefully I can tinker a few hours today. Just using the parking brake also crossed my minded, will try that with the addition of a few lander legs and wheel wells to get the base components to stay in one spot.

[Spartwo]

Drive to it it's only 100k.

[boxman]

If you dont mind a design change you could also try to put the docking port underneath the rover at center and on the floor of what you dock at. Not only is it easier to dock, but in my experience it keeps it more stable than one docking port in front or back.

If you put the docking ports so that they have just a tiny bit of clearance from eachother you can simply just dock by driving the rover over the docking port, which will activate magnitization which will push the rover down enough to dock automatically.

[Thorbane]

You could use a skycrane with electromagnets from the KAS mod. A design with 4 LV-Ns should get you off the ground and where you need to go. Just remember to bring the RTGs to power the magnets indefinitely, you Do Not want to lose power on those while in flight.

[The Destroyer]

Why not land some mainsails with aircraft landing gear on the Mun, and PUSH IT UP! Then, attach wheels and drive it.

[Whackjob]

May I suggest a skycrane? I see docking ports above the station. Build a mirror image docking structure, add rockets and fuel, and drop it on top the rovers. Then haul it off.

It'd be tricky to do, but appears less tricky than the other options.

[Merinsan]

As cool as the barge looks, it will never work as you intend, due to the way physics works with a single ship.

If you dock it on one side only, all thrust is going to go to that port, and the other side will bend down, through the barge floor (since collisions don't work on the same ship parts). You can achieve the same effect without the barge, just have the docking port.

Most likely the reason the thing is exploding is while docking, the thing is moving to get aligned and colliding.

You really only have 2 stock options.

1. Even docking, ie docking on both sides

2. Using landing legs to secure the load - DO NOT use time acceleration while doing this, as collisions get turned off and things will clip through.

In the past when I have wanted to move a base, I finally did it by sending up a new base, deleting the old one and pretending I actually moved it.

[DeepSpaceDutch]

Thanks for all the suggestions guys!

Still going with the flying platform type thing, using lander legs to secure the load. I think I have a workable craft now, still a little low on fuel though. Also it's a bit of a bitch to handle, especially loaded. But hey, we all like a good challenge now don't we? I did succeed in making a few hops around the launch complex, loaded and unloaded. Did have some nice crashes, unfortunately I was so busy I forgot to take screenshots of them.

Also I had to abandon the idea of transporting both types of base components with one type of platform, they are just too different. So I'm only taking the hab modules, two of them, so two trips. I'll leave the light tower/node component, maybe I'll drive it over later.

Here a few screenies of the dev work;

Platform lay-out complete. The wheel wells make sure the load doesn't move forward or aft.

Yay, it fits live a glove!

Rolling back is covered by the addition of two lander legs.

A few itirations down the line we have the beginnings of the fuel system and engine supports, the three fuel tanks at the back are for balance and will not be used. Also we now have four middle sized lander legs making sure the load doesn't move upwards.

This things isn't going anywhere!

Fighting for control with just two reaction wheels, this ended crashy I might add.

Aaahhh much much better!

Still fits..

Whheeeeeyyyyyy...

Refueling the platform from the hab module. The fuel in the hab modules is probably not going to be enough for going back and forth between the two locations. So I might have to send along a refueling module. Very inefficient, but Kerbal logic is very different from Human logic. They value challenge and stupid but entertaining behaviour above efficiency and safety, and they're damn right!

Any feedback is much appreciated!

Edited August 11, 2013 by DeepSpaceDutch

[DeepSpaceDutch]

2. Using landing legs to secure the load - DO NOT use time acceleration while doing this, as collisions get turned off and things will clip through.

Gotcha, thanks!

[Tw1]

Looking good! As long as you land right, you should have your base relocated soon enough.

Driving is not that practical, to travel 100km and back with a crane would take ages. I've done it over shorter distances, but that's too far to go there and back.

To be clear; using cables to hold the Hab module up so that it doesn't collide with the structure when docking, correct?

Yep. But you seem to be on top of things with your current system.

Edited August 11, 2013 by Tw1

[el_coyoto]

Thanks for all the suggestions guys!

Still going with the flying platform type thing, using lander legs to secure the load. I think I have a workable craft now, still a little low on fuel though. Also it's a bit of a bitch to handle, especially loaded. But hey, we all like a good challenge now don't we? I did succeed in making a few hops around the launch complex, loaded and unloaded. Did have some nice crashes, unfortunately I was so busy I forgot to take screenshots of them.

Also I had to abandon the idea of transporting both types of base components with one type of platform, they are just too different. So I'm only taking the hab modules, two of them, so two trips. I'll leave the light tower/node component, maybe I'll drive it over later.

Here a few screenies of the dev work;

Platform lay-out complete. The wheel wells make sure the load doesn't move forward or aft.

Yay, it fits live a glove!

Rolling back is covered by the addition of two lander legs.

A few itirations down the line we have the beginnings of the fuel system and engine supports, the three fuel tanks at the back are for balance and will not be used. Also we now have four middle sized lander legs making sure the load doesn't move upwards.

This things isn't going anywhere!

Fighting for control with just two reaction wheels, this ended crashy I might add.

Aaahhh much much better!

Still fits..

Whheeeeeyyyyyy...

Refueling the platform from the hab module. The fuel in the hab modules is probably not going to be enough for going back and forth between the two locations. So I might have to send along a refueling module. Very inefficient, but Kerbal logic is very different from Human logic. They value challenge and stupid but entertaining behaviour above efficiency and safety, and they're damn right!

Any feedback is much appreciated!

I see that your tests are going well, that's good. The platform looks really good and it must have been a challenge to get something like this to work with the toon physics, congratulations!

Can't wait to see your base proudly sitting next to the Neil Armstrong Memorial!