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Docking makes me want to kill things.


Sekonda
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If I can do it, anyone can!! And I just eyeball it in. I use mechjecb to get close and then to match velocities. From there I eyeball it in and although every now and then I get a difficult one, I usually have not too much issues.

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It's like anything else in life. Practice makes perfect, and quite often beer helps. A lot.

I've probably done a couple hundred dockings by now, some quite complex multi-port ones with ships with no RCS. It is now second nature. Just keep doing it and you'll get better, and probably one day soon you'll think back to this thread and say to yourself: "self, look how far I've come"!

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Two of the worst things when trying to dock is:

A) having the RCS thrusters not distributed evenly around the CoM, so your craft will veer like mad on every RCC burst,

making it virtually impossible to manouver precisely.

B) Not going slooooooowly.

Always try to limit your controls to one axis at a time, bring your craft to a full stop, then align another axis.

Rinse and repeat.

Don't ever get hasty. If you feel stressed, you are doing it wrong.

Bonus tip: Make sure the craft or station you want to dock to has its SAS activated in "stability" mode,

to prevent it from beginning to rotate around all 3 axis when accidently bumping into it during docking.

And I recommend this for training:

After 3-5 attemps, you should be able to get reproducible results.

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(1) Ignore all advice.

(2) Do not use the stock 'docking mode', use the translation key bindings with the right hand.

(3) Do not learn in low orbit. Docking is much easier at 2000+km where relative motions are smaller.

(4) Do not use maneuver nodes. Learn to intercept in stages (launch, alignment, phasing orbits etc)

(4) Do not try docking until you are 100% on node-free interceptions.

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Splendid advice all around.

To make things even simpler, do this:

1) Launch a passive docking target into a 150x150km equatorial orbit. It does not need to be a ship, just a junior docking port connected to a probe core and maybe a structural girder if you want it to look bigger. The probe core has SAS so it can orient itself whichever way you want. Leave it there and return to space center.

2) Send aloft a Mk.1 capsule with junior docking port at the top, an RCS tank (or two) and a small fuel tank with LV-909. Bring bigger fuel tank if you're not up to speed on orbital interceptions.

Wait for the docking target to complete 3/4 of its orbit, coming back to KSC from the west. When it passes the desert area, spawn the interception capsule and target the docking target. It doesn't matter if you launch too late to intercept on the ascent itself. In fact what you want to do is launch eastwards behind the docking target, and establish a 70km x 70km orbit "under" and "behind" it.

You will then be able to plot a maneuver node to intercept the docking target at a very low relative velocity, brake when you're about 2km from it and use RCS to slowly dock. Once you cancel target relative velocity to zero you are in the exact same orbit.

This practise will rapidly enable you to proceed onwards to space station assembly, crewing and maintenance, plus rescue missions, because you will be doing active interceptions on passive targets all the time. If you miss or run out of fuel, that's fine, just watch how the orbits affect craft motion - lower orbits are faster, higher orbits are slower, that's why launching behind a docking target is simplest.

3) Go on to do practise rendezvous with debris, random satellites including those requiring orbital plane matching, moons, etc. You'll get a hang of the difference between a slow transfer and a fast one, and note the differences between a direct ascent to target (requiring huge dV to match velocity due to extreme closure speeds but insufficient orbital velocity) and a gradual rendezvous (like the first test scenario, the closure should be something less than 50m/s).

Edited by pandoras kitten
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(1) Ignore all advice.

(2) Do not use the stock 'docking mode', use the translation key bindings with the right hand.

(3) Do not learn in low orbit. Docking is much easier at 2000+km where relative motions are smaller.

(4) Do not use maneuver nodes. Learn to intercept in stages (launch, alignment, phasing orbits etc)

(4) Do not try docking until you are 100% on node-free interceptions.

This is fairly solid advice, but I have some to add. I dock things constantly and perfectly. I bring less than 100 monoprop on ships that use docking to reconfigure and rendezvous at least 15 different times.

(5) If possible, instead of turning off SAS like most will suggest, align both ships vertically. Its the one point on the navball that won't move or decieve you as you continue to orbit, even at huge inclinations.

(6) With the Rcs controls, if your control point's direction is unknown, fire the RCS in tiny bursts a few times to see where your RCS is aligned, then realign yourself and your camera to make sense.

(7) As Sandworm said, NEVER use maneuver nodes. Learn to read the information that show on the navball when it is in "target" mode, targetting your rendezvous goal. Retrograde will become the direction which your ship much burn in order to nullify your relative speed, and prograde, the opposite.

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(4) Do not use maneuver nodes. Learn to intercept in stages (launch, alignment, phasing orbits etc)

(4) Do not try docking until you are 100% on node-free interceptions.

Seems like pretty bad advice to me personally. I can dock just fine, but I use nodes on the timing and to fine-tune my burns. I had to learn how to eye-ball orbital maneuvers first, I would have put a 9mm through my screen by now.

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The most solid advice: if you consider docking, be sure your crafts are orbiting in the same direction. :D

*reminiscence* First docking attempt in Munar orbit. Perfect encounter after half an hour RCS fiddling. Spectacular orbital velocity collision. Much butthurt. Yeah, those were the days. *reminiscence*

Edited by Bloody_looser
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The most solid advice: if you consider docking, be sure your crafts are orbiting in the same direction. :D

*reminiscence* First docking attempt in Munar orbit. Perfect encounter after half an hour RCS fiddling. Spectacular orbital velocity collision. Much butthurt. Yeah, those were the days. *reminiscence*

Ahh the memories. I learnt this lesson during a mission to Jool.... I'd sent a refuelling mission because I'd severely under-engineered my ship. It was floating around with naught but RCS fuel. I just did not understand why I could not get a solid encounter.... until I did... and the answer wizzed by me at many, many, many meters a second.

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...I just spent 90 minutes with it dancing over the lip of my Docking Port Snr, over and over and over, finest dances, over and over and over, but it was never enough to capture...

So can we please stop telling this guy how to rendezvous? :)

Careful with those Docking Port SNr's. If you're not paying attention, it's possible to install them backwards, in which case they don't work. I had this happen to me a while back. Rule of thumb, if you right click on the port you should have an option for "Control From Here". If you're not seeing that, the port is on backwards.

I wanted to suggest that too. Sekonda, if you haven't resolved the problem yet, I'd recommend checking for this. The seniors have a nasty habit of looking the same at both ends, and if you put one on the bottom of a stack in the VAB... yeah.

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I'm coming in way late to this thread, mostly just to add: I love the title. :D

We've all been there. But, like motorcycling, abseiling, and most things in KSP, once you get the hang of it you realise that it really isn't that big a deal.

Just hang in there and eventually it'll click. In the meantime, make it easy on yourself by building not-too-big ships with well-balanced RCS. Walk before you run.

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Seems like pretty bad advice to me personally. I can dock just fine, but I use nodes on the timing and to fine-tune my burns. I had to learn how to eye-ball orbital maneuvers first, I would have put a 9mm through my screen by now.

I don't mean that you should eyeball approaches. If you do things in stages you should be able to intercept and park beside the target all from the map view using only the stock guides on the orbits. Once you have a coplaner+phasing orbit established you can do a burn to bring the next approach within 1-200m. The result is a much slower and more predictable interception. There are many advantages to this over maneuver nodes. The biggest for beginners is probably that it allows you to place the interception point wherever you want, preferably just after dawn so docking can occur in the light. I like to place it slightly before dawn so that as I reduce my relative velocity it moves into dawn.

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I can get an intercept and meet the target; my issue is the last 20m of docking. RCS gives me a headache.

Strafe controls are your friend!

Get to a good orientation and 0 m/s (or close) relative to your target, then stop changing your orientation and start strafing.

h - Forward

n - Backward

j - Left

k - Down

I - Up

l - Right

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Just made a quick mock-up of OP's craft, and purposefully went in to dock off center. The docking ports still attached after a second, so it's not a positioning issue.

Docking ports on the hub are the right way out, and though the one on the module looks flush with the science bay, it might be good to check that it's turned the right way 'round.

If THAT checks out, then see: http://forum.kerbalspaceprogram.com/threads/78863-FIX-Dock-Undocking-Bug-in-0-23-5 (third post)

Same bug happened to me when trying to make a munbase. Drove me crazy too wondering why stuff wouldn't fit. :D

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Strafe controls are your friend!

Get to a good orientation and 0 m/s (or close) relative to your target, then stop changing your orientation and start strafing.

h - Forward

n - Backward

j - Left

k - Down

I - Up

l - Right

Yes, but you have something reversed.

When the velocity vector is too far left on the navball, you push the "L" key and it moves right. When the velocity vector is too far to the right, you push the "J" key and it moves left. So far, so good. But when the vector is too far up, you don't push the "K" key to move it down. Instead, you push the "I" key to move it down. Similarly, when the vector is too far down you push the "K" key to move it up.

Apparently the keys were selected to be like an airplane control column, and pulling back ("K") makes the ship translate up, while pushing forward ("I") makes it translate down.

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Also make sure your Clampotron Sr. docking ports are on the right way. It sounds dumb, but if you don't pay particular attention to it, it's easy to put the docking port on backwards. I did that one time and couldn't figure out for the life of me why it wouldn't dock. :wink:

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Strafe controls are your friend!

Get to a good orientation and 0 m/s (or close) relative to your target, then stop changing your orientation and start strafing.

So my problem is trying to visualize the vector I need for the target and try to aim that way correctly. Also, Getting to exactly 0m/s relative motion in all three dimensions relative to the target is hard :/

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If you can, it's much easier to have the target point to you. First you point the docking ship at the target. Then you switch to the target and control from the docking port of interest. You point that toward the docking ship, then use SAS or Mechjeb to lock the rotation. Finally, you switch back to the docking ship and specifically target the docking port you want. Now you are basically lined up, and all you have to do is compensate for drift.

This is not always possible, because sometimes your target vessel is either not owned by you or is otherwise uncontrollable. Or it may not have SAS on board, which makes the tactic much less useful.

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So my problem is trying to visualize the vector I need for the target and try to aim that way correctly. Also, Getting to exactly 0m/s relative motion in all three dimensions relative to the target is hard :/

Getting 0 m/s is straightforward. Make sure your Navball is configured on "target" and burn retrograd. When you are close to 0, use RCS (H and N keys in docking mode) for fine tuning.

Navball is the key. Docking alignment indicator helps, but your primary tool remains the navball.

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Don't know if this was mentioned before. But take your time doing dockings and rendevouz maneuvers. I generally do all of my docking really slow so i have plenty of time to adapt and align everything.

When you are close, face towards the target (set a specific docking port as a target) marker and try to get your prograde marker onto that. Which would mean your trajectory is going to be on that docking port. Then very slowly do RCS bursts to align everything before you actually dock.

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