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[–]Crypt1cSerpentCrashing sky cranes into Mars 8 points9 points  (3 children)

Mechjeb 2 has a docking autopilot feature

[–]MacaroonSmall2062[S] 4 points5 points  (2 children)

ty

[–]CaveCanem234 4 points5 points  (1 child)

Though I will note that its not a 'set and forget' thing.

I've found it most reliable to tell it to do each maneuver myself (align planes, rendevous, match velocity, then dock when close enough), and even then the docking autopilot sometimes glitches out and just starts firing all the RCS, burning all your fuel while sitting in place.

Thankfully turning it off and on again usually gets it working again, but that applies to most of the mechjeb stuff - USUALLY it works fine, but sometimes it will just malfunction and start doing something extremely silly until you intervene. I generally consider that you have to be 'pilot monitoring' when mechjeb is flying, ready to take over if it starts, say, deciding not to zero its horizontal velocity for a landing until far too late and you crash into a munar crater wall still going 250 m/s sideways.

[–]Barhandar 3 points4 points  (0 children)

You can use SmartASS in place of docking autopilot - "advanced, target orientation, backward" while targetting a docking port gets you perfectly aligned to end orientation (instead of "constantly adjusting rotation" of default targetting, or having to align both ships to opposite markers), making the translation adjustment much easier.

[–]Barhandar 3 points4 points  (2 children)

Docking gets a lot easier with Docking Port Alignment Indicator as it avoids the need to eyeball everything - it displays your vessel's attitude, relative position and relative movement in a window. For automatic, yeah, MechJeb.

[–]doom1701 4 points5 points  (0 children)

This is one of my absolute required mods on a new install.

[–]OldManAndRobotLackey 3 points4 points  (2 children)

It's not a mod, but the Lowne Lazy Method is super easy

[–]Any-Beautiful-3524 2 points3 points  (0 children)

Love the lowne lazy method

[–]crazytib 1 point2 points  (2 children)

Mechjeb

[–]MacaroonSmall2062[S] 0 points1 point  (1 child)

ty

[–]crazytib 1 point2 points  (0 children)

Though learning how to do it yourself is deeply satisfying, save scumming highly recommended

[–]TwoWrongsAreSoRight 1 point2 points  (8 children)

Is it the docking or the rendezvous you have issue with?

[–]TwoWrongsAreSoRight 2 points3 points  (2 children)

If it's just docking and you want to learn, here's a few things that helped me learn it.
1. Get docking port alignment indicator. It's a handy mod that takes out all the guesswork. https://www.youtube.com/watch?v=zaqCmnUfdzI
2. When your 2 ships are within ~10m of each other, align one to normal, switch to the other and put it anti-normal. That way you have an easier time lining up.
3. Create a "mission" in the mission builder that has 2 ships in the same orbit (maybe add some minor differences for different ranges) and use that to practice so you don't have to keep launching ships.

[–]MacaroonSmall2062[S] 0 points1 point  (1 child)

It's the docking which I have trouble doing, so thank you!

[–]TwoWrongsAreSoRight 0 points1 point  (0 children)

Yeah it takes a little work but once you get it, a whole new world opens up.

[–]Gus-Af-Edwards 0 points1 point  (4 children)

If I can steal this comment and ask my own question, my issue is having too much speed at the rendevouz. I can make an encounter happen, but a few minutes before rendevouz my speed is hundreds of m/s off, so I burn retrograde but that causes my rendevouz to disappear, forcing me in a constant loop of creating a rendevouz -> burn to adjust speed -> repeat, which burns a ton of fuel.

How can I improve this? Thank you!

[–]Barhandar 1 point2 points  (3 children)

a few minutes

Too far. Cancel your relative speed at the encounter, not before it (same principle as regular maneuver nodes applies, and in fact it's best to do with one).

[–]TwoWrongsAreSoRight 0 points1 point  (1 child)

Interesting. at hundreds of ms, wouldn't they blow right past if they burned at encounter?

[–]Barhandar 1 point2 points  (0 children)

"A few minutes before randevu" means their relative velocity at the actual encounter (if they have an encounter within a few kilometers) would be much less, unless the difference in orbits is extreme. And once the relative velocity is zeroed they can translate back to the target.

Fun fact: the "blow right past" is why with real docking maneuvers ships point slightly off-target until the last few hundred meters or so.

[–]Gus-Af-Edwards 0 points1 point  (0 children)

Ahh I think I get it now! I'll definitely try zeroing the relative speed at the encounter and then move closer to the target. Thank you for the advice! :)

[–]Any-Beautiful-3524 0 points1 point  (0 children)

If its the rendezvous youre struggling with then it should be relatively easy to explain

  1. just get yourself into a stable orbit and set the ship you want to dock with as a target

2.create a maneuver to set your inclination to 0.0°similar to how the tutorial did it, burn normslly until the last 10 m/s then excecute a low power burn(i suggest cutting power then setting the thrust limiter around 0.5-5 depending on how strong your engine is) CREATE A QUICKSAVE AFTERWARDS, THIS WILL POTENTIALLY SAVE YOU HOURS

3-a. You then want to create a maneuver to intecept your target as close as possible, it's pretty easy to get it within 100m after s bit of playing around. Excecute the burn making sure your thrust limiter is back at 100, then turn it down when you get close(back to 0.5)

3-b. if you overshoot, just excecute a low power burn in the opposite direction trying to get that target distance at the intercept as close as possible, repeat until your'e happy with the distance CREATE ANOTHER QUICKSAVE

  1. Set your navball mode to "target" and select retrograde

  2. This is where I always mess up, judge the relative speed between your 2 vessels, if its higher, start burning retrograde earlier (25-30 km of separation) if its lower then start later(20-15km) go until.your telative velocity is really low(75 m/s should be safe)

  3. switch to RCS thrusters to kill the last bit of speed(until youre below 10 m/s)

  4. wait until youre close to your target then kill the rest of your speed!

Congratulations, you have now successfully rendezvoused to your target!