totm january 2020 Community Caveman Jool 5 mission

[Muetdhiver]

I'll gladly dock something to it after @IncongruousGoat

As an aside I have been doing a lot a ladder riding and I am a bit worried about RCS fuel. Though it seems drift can be kept low so long as the ladder is not orientated prograde before release. This will be the strongest constraint IMO.

I would suggest to move the ship rather than the kerbal, unless we are doing an interplanetary transfer.

[ManEatingApe]

33 minutes ago, Muetdhiver said:

I'll gladly dock something to it after @IncongruousGoat

Great, I've added you to the queue.

34 minutes ago, Muetdhiver said:

As an aside I have been doing a lot a ladder riding and I am a bit worried about RCS fuel. Though it seems drift can be kept low so long as the ladder is not orientated prograde before release. This will be the strongest constraint IMO.

I would suggest to move the ship rather than the kerbal, unless we are doing an interplanetary transfer.

Agreed. We'll need to be careful and economical with the Kerbal's EVA jet-pack fuel.
600 m/s is a lot initially but as each time warp means a rendezvous there will be a lot of them!

[IncongruousGoat]

9 hours ago, Muetdhiver said:

Though it seems drift can be kept low so long as the ladder is not orientated prograde before release.

My finding (from the research I did into this way back at the start of the thread) was that having the ladder facing radial in was best overall. But yes, prograde bad, retrograde bad, radial out weird, normal/antinormal sometimes ok, radial in good.

@ManEatingApe PR submitted with the third FOXTROT and the first TANGO docked to MIKE.
Based on the mothership mockup that showed up a few pages ago in the thread, it looks like we're going to need 4 more FOXTROT launches - 3 more drop tanks, and then one with extra fuel for KILO/LIMA. Is this still accurate, or should one of us make a new reference mockup?

Edited September 14, 2019 by IncongruousGoat

[ManEatingApe]

1 hour ago, IncongruousGoat said:

Based on the mothership mockup that showed up a few pages ago in the thread, it looks like we're going to need 4 more FOXTROT launches - 3 more drop tanks, and then one with extra fuel for KILO/LIMA. Is this still accurate, or should one of us make a new reference mockup?

Yup, that's still the plan!

Once your changes are merged, we will need:

• 4 x FOXTROT (3 for MIKE, 1 for TANGO+BRAVO combo)
• 2 x TANGO
• 1 x KILO
• 1 x LIMA
• 1 x KILOLIMA fuel

These missions can run in any order (with the exception of KILOLIMA which I believe needs to go before LIMA to assemble properly).
That makes 9 launches remaining. To speed things up a little I suggest that we do them 2 at a time if folks are up for it.

EDIT:

1 hour ago, IncongruousGoat said:

PR submitted with the third FOXTROT and the first TANGO docked to MIKE.

Thanks for the contribution! Things are shaping up nicely.
@Jacke Passing the mutex to you.

Wonderful folks on this forum, if anyone would like to contribute with a mission to LKO and orbital rendezvous, please don't feel shy, volunteers are welcome
The save game is public, so anyone can download it to try things out.

Edited September 14, 2019 by ManEatingApe

[Jacke]

I can try two TANGO's in succession.

EDIT: Ack, I have mutex.

Edited September 14, 2019 by Jacke

[Jacke]

I've created a pull request adding tango-2-1.sfs and tango-2-1.loadmeta, which has the following changes with respect to lastest.sfs, which my pull request doesn't change.

MIKE is in 80.3x80.3km orbit

TANGO #2 is in roughly co-planar orbit 78.7x80.4km trailing MIKE by about 15 degrees.  There's 214m/s delta-V remaining in the launch stage #2.

I now realise that Caveman means no targeting.  And the vessel designs mean no RCS.  Alas, that's well beyond my ability to go through close rendezvous and docking.

Passing mutex back to you, @ManEatingApe.  Leave it up to you to either complete my TANGO launch or go back and do it from launch.

If you use my TANGO, note that it is at Naming Priority 10 (forgot to drop it to 9), so it will rename MIKE after docking, needing another rename back to MIKE.

Edited September 14, 2019 by Jacke

[ManEatingApe]

17 hours ago, Jacke said:

I've created a pull request adding tango-2-1.sfs and tango-2-1.loadmeta, which has the following changes with respect to lastest.sfs, which my pull request doesn't change.

MIKE is in 80.3x80.3km orbit

TANGO #2 is in roughly co-planar orbit 78.7x80.4km trailing MIKE by about 15 degrees.  There's 214m/s delta-V remaining in the launch stage #2.

I now realise that Caveman means no targeting.  And the vessel designs mean no RCS.  Alas, that's well beyond my ability to go through close rendezvous and docking.

Passing mutex back to you, @ManEatingApe.  Leave it up to you to either complete my TANGO launch or go back and do it from launch.

You can still get target mode in Caveman by selecting the other craft (double clicking on the target box) once close enough (about 30km).

This will give you relative velocity and target markers on the navball.

No RCS is workable as the docking port is aligned with the ship axis of thrust. Give yourself a velocity of 0 relative to the target, aim as best you can, rinse and repeat. The docking port are a little forgiving if you come in at an angle, the magnets will drag the lightweight lander into position.

Edited September 15, 2019 by ManEatingApe

[Jacke]

1 hour ago, ManEatingApe said:

You can still get target mode in Caveman by selecting the other craft (double clicking on the target box) once close enough (about 30km).

This will give you relative velocity and target markers on the navball.

No RCS is workable as the docking port is aligned with the ship axis of thrust. Give yourself a velocity of 0 relative to the target, aim as best you can, rinse and repeat. The docking port are a little forgiving if you come in at an angle, the magnets willbdrag the lightweight lander into position.

Thanks for that advice, @ManEatingApe.  (Can't give you a like as that's disabled by Squad right now.)  Okay, I have the mutex.

Took like 3d ingame waiting for the close approach after several orbits, but should be able to at least complete rendezvous.

EDIT: As I discovered, there's 3 piece of debris floating around MIKE.  I could dispose of them via the Tracking Station.  Let me know if I should.

Edited September 14, 2019 by Jacke

[Jacke]

Rendezvoused TANGO #2 with MIKE.

Tried for 25 minutes to dock using only 2nd stage engine, decreased to 10% of its rated thrust. My pass was misaligned and I had to move away and kill relative velocity.

Afraid I'm not up to docking with just the main engine. Was very stingy with the delta-V and still has 185m/s even after failed docking attempt.

Created a pull request with 6 files with these 3 states.  Mutex back to you, @ManEatingApe.

New files:
tango-2-1.sfs & .loadmeta
TANGO #2 trailing MIKE with close pass in several orbits, 214m/s delta-V

Spoiler

 

tango-2-2.sfs & .loadmeta
TANGO #2 rendezvoused with MIKE within 20m, under 0.1m/s relative, 186m/s delta-V

Spoiler

 

tango-2-3.sfs & .loadmeta
TANGO #2 after failed docking attempt, within 15m, under 0.1m/s relative, 185m/s delta-V

Spoiler

 

[IncongruousGoat]

38 minutes ago, Jacke said:

Afraid I'm not up to docking with just the main engine. Was very stingy with the delta-V and still has 185m/s even after failed docking attempt.

Yeah, trying to do an actual docking with TANGO is painful. The trick is to, after you get close and kill relative velocity, switch to MIKE, target the docking port on TANGO, control from the port on MIKE you want to dock to, and then point the port on MIKE straight at TANGO. From there the docking is relatively easy since it's just point and nudge. MIKE has really good control authority, so it's a lot easier to just reorient it than it is to try and fly around and dock properly with TANGO.

[Jacke]

11 minutes ago, IncongruousGoat said:

Yeah, trying to do an actual docking with TANGO is painful. The trick is to, after you get close and kill relative velocity, switch to MIKE, target the docking port on TANGO, control from the port on MIKE you want to dock to, and then point the port on MIKE straight at TANGO. From there the docking is relatively easy since it's just point and nudge. MIKE has really good control authority, so it's a lot easier to just reorient it than it is to try and fly around and dock properly with TANGO.

Should have done that, but I'm kind of worn out by this.  Don't have the Caveman stamina that you old salts do.

EDIT: Okay, one more try.  Taking the mutex back, @ManEatingApe.

Edited September 15, 2019 by Jacke

[Jacke]

Tried one docking but wasn't aligned right and bounced.  Trying again.

Is there a faster way to switch between spacecraft besides going to the Tracking Station?

I don't have a good switcher mod like Targetron installed right now and though it would only take me a few minutes to exit, install, and relaunch, I'd like to avoid that.

[Jacke]

Tried several times and couldn't get a docking straight enough to lock, but just bounced off, closing at about 0.5m/s.  Couldn't get an aligned approach at a lower relative velocity.

No change to my pull request.  As is above.  Mutex back to you, @ManEatingApe.

[IncongruousGoat]

17 minutes ago, Jacke said:

Is there a faster way to switch between spacecraft besides going to the Tracking Station?

Left Bracket/Right Bracket cycle forward and backward through the vessels whose physics is currently being calculated (i.e. everything within the 2.3km sphere of physics).

[Jacke]

12 minutes ago, IncongruousGoat said:

Left Bracket/Right Bracket cycle forward and backward through the vessels whose physics is currently being calculated (i.e. everything within the 2.3km sphere of physics).

Thanks!  Keep forgetting that one.

Glad I at least tried to dock.  I now really understand why real non-linear spacestations are assembled with manipulator arms.

[dvader]

@ManEatingApe Sign me up for anything you want. I would especially like to try the FOXTROT since I can still not believe it works Anything else would also be fine.

As a side note, I think KILO is now 2.45t and not 3t like before. Should I add an extra 0.56t tank to the KILOLIMA fuel mission just for balance? We don't really need KILOLIMAs extra fuel or the extra tank for anything but MIKEs balance.

[ManEatingApe]

@Jacke Kudos for that perfect orbital rendezvous. It's not easy to get 2 ships close without maneuver nodes.
You're so close (figuratively and literally) so if you'd like to try again, I'd be delighted to add you to the mission queue.

Your rendezvous technique is spot on, for others reading the steps are:

• Align inclination by eye as close as possible
• Match orbits almost exactly with the target vessel
• Leave your orbit slightly smaller or larger so that you slowly catch-up with the target vessel (or it catches-up with you)
• Time warp patiently (it's perfectly fine if this takes days, time is not important)
• Once within 30km, select the other vessel as a target in normal (not map) view
• At the closest point with other vessel, kill relative velocity (set navball to target mode)
• Point directly at target vessel and burn. Not too hard.
• Once within 1km kill relative velocity, then rinse and repeat until very close (<20m)

I took your save and applied @IncongruousGoat's docking technique:

• Make sure vessels are close and relative velocity is zero.
• Switch to 1st vessel
• Select docking port then "Control from here"
• Select target docking port on 2nd vessel and set as target
• Rotate vessel to face docking port (using navball target marker)
• Tiny thrust towards target vessel ~1m/s
• Switch to 2nd vessel
• Select target docking port then "Control from here"
• Select incoming vessel and set docking port as target
• Rotate vessel to face docking port - now both docking ports are facing each other.
• Rinse and repeat until success

Here's the docking from where you left off. I've committed and tagged this as "v12". Everyone please pull the latest changes.

 

6 hours ago, dvader said:

Sign me up for anything you want. I would especially like to try the FOXTROT since I can still not believe it works Anything else would also be fine.

Great! Added you to the queue for a FOXTROT.
I'm quite enjoying the infamous reputation this innocent craft seems to have acquired...
The trick is to do nothing (except stage once) until about 40km, then fly a very flat ascent profile.

6 hours ago, dvader said:

As a side note, I think KILO is now 2.45t and not 3t like before. Should I add an extra 0.56t tank to the KILOLIMA fuel mission just for balance? We don't really need KILOLIMAs extra fuel or the extra tank for anything but MIKEs balance.

Yes, I think this is a good idea. The extra fuel gives us extra flexibility both in Laythe rendevous, final Kerbin return and keeps MIKE controllable.
MIKE has plenty of dV even with the extra mass.

 

@Muetdhiver The mutex is yours!

Edited September 15, 2019 by ManEatingApe

[Rakaydos]

25 minutes ago, ManEatingApe said:

Here's the docking from where you left off. I've committed and tagged this as "v12". Everyone please pull the latest changes.

 

As someone who did literally dozens of caveman dockings for my own project, I winced.

Reccomend enough relative velocity to get a navball relative velocity marker, then use it to correct your course on the way in. If you get too much speed at docking and bounce, tap and shut off the throttle while still in magnet range to stay in contact. Nothing's going to break unless you're going over 5m/s, which you shouldnt be, so you dont need to be quite so gentle when you have plenty of rendevus fuel.

Edited September 15, 2019 by Rakaydos

[ManEatingApe]

24 minutes ago, Rakaydos said:

As someone who did literally dozens of caveman dockings for my own project, I winced.

Reccomend enough relative velocity to get a navball relative velocity marker, then use it to correct your course on the way in. If you get too much speed at docking and bounce, tap and shut off the throttle while still in magnet range to stay in contact. Nothing's going to break unless you're going over 5m/s, which you shouldnt be, so you dont need to be quite so gentle when you have plenty of rendevus fuel.

That's a good suggestion. As a veteran of many Caveman dockings, volunteer for a mission if you like, the more the merrier!

[Rakaydos]

How do I use Github?

[ManEatingApe]

59 minutes ago, Rakaydos said:

How do I use Github?

Well...if you think Caveman interplanetary is tough, get ready for a new and interesting challenge!
Just kidding, although Git does have quite a steep learning curve, so some reading is required.
Git has major mind share, so finding guides and documentation to achieve anything you want (no matter how obscure) is straightforward.

Here are 3 recent guides:
https://guides.github.com/introduction/git-handbook/
https://product.hubspot.com/blog/git-and-github-tutorial-for-beginners
https://www.elegantthemes.com/blog/resources/git-and-github-a-beginners-guide-for-complete-newbies

The simplest possible flow is:

• Fork the repo in Github when it's your turn (deleting any previous versions first)
• Clone the repo locally (also deleting any previous versions first)
• Fly your mission, saving as "latest.sfs" when finished.
• Create a branch
• Commit the "latest.sfs" and "latest.loadmeta" files only
• Push local branch to your remote fork
• Open a PR from your fork to the original repo
• I will review the PR and if all is well, merge it, making it available to other contributors.

Like docking it's a little tricky the first time around, but you'll get the hang of it in no time.
The core Git concepts of decentralization, forking, cloning, a DAG structure, committing, branching and merging also make interesting bed-time reading.

As a last-ditch plan B (although I would strongly encourage folks to make an effort to use Github) you can:

• Download a ZIP of the latest save file when it's your turn from
  https://github.com/maneatingape/community-caveman-jool-5/releases
  (deleting any previous versions)
• Fly your mission
• Upload the "latest.sfs" file somewhere publically available e.g. Dropbox
• I will download the file, review it, and if all is well, merge it to the repo in Github on your behalf.

Edited September 15, 2019 by ManEatingApe

[Rakaydos]

I just downloaded Foxtrot, since it seems to be what the group is having the most trouble with.

I dont have a feel yet for when to stage to get a good orbit, but I'm working on it.

Edit: got it, circularized at 79.06 x79.12 with 160 m/s in the tanks, according to stock DV

Edited September 15, 2019 by Rakaydos

[IncongruousGoat]

1 minute ago, Rakaydos said:

I just downloaded Foxtrot, since it seems to be what the group is having the most trouble with.

I dont have a feel yet for when to stage to get a good orbit, but I'm working on it.

@ManEatingApe posted some guidance somewhere earlier in the thread that does a good job of covering how to fly FOXTROT. It worked fine for me, in any case. The gist is that, after turning SAS on, you shouldn't touch any controls other than stage until your Ap is at 80 km.

[Jacke]

26 minutes ago, Rakaydos said:

I just downloaded Foxtrot, since it seems to be what the group is having the most trouble with.

You also want latest.sfs and latest.loadmeta so you can load the current state.

 

Quote

I dont have a feel yet for when to stage to get a good orbit, but I'm working on it.

Monitor any of the 4 lower tanks with a Part Action Window (right-click on the tank and pin it somewhere).  When they are empty (recent fuel flow algorithm now empties them all equally), that's when you stage.

@ManEatingApe had a more detailed guide in this post.

You want to use KSP 1.7's Maneuver mode displace (click the lower of 4 buttons on the right side of the Staging widget on the lower left of the screen) to be able to see the Apoapsis in flight mode.

Beyond that, when sufficiently high (maybe even before staging, but under Apoapsis of 80km) you want to flatten out a bit to improve the efficiency of the later burn and minimize the orbital insertion burn.  Else you run out of 2nd stage propellants before getting circularized.  I ended up at 54x79km.

Edited September 15, 2019 by Jacke

[Jacke]

3 hours ago, ManEatingApe said:

@Jacke Kudos for that perfect orbital rendezvous. It's not easy to get 2 ships close without maneuver nodes.
You're so close (figuratively and literally) so if you'd like to try again, I'd be delighted to add you to the mission queue.

Thanks.  That docking was really tough and I think it's best we give the others a try.

I'm more of a balanced RCS builder, can now do so even without mod aid.  I'm now thinking that I can do orbital assembly well enough for a Caveman NCD career.

 

1 hour ago, ManEatingApe said:

Well...if you think Caveman interplanetary is tough, get ready for a new and interesting challenge!
Just kidding, although Git does have quite a steep learning curve, so some reading is required.
Git has major mind share, so finding guides and documentation to achieve anything you want (no matter how obscure) is straightforward.

Alas, GitHub has a crappy interface.  I understand the basics to Git, but GitHub makes things so hard.

Just figured out how to delete my previous fork of @ManEatingApe's repro.

But now I can't figure out how to fork it again.  Even after doing so before.   And figured it out.

Edited September 15, 2019 by Jacke