KSP Stock : Docking Difficulty Absurdtastic?

[Andr0s]

Hiya y'all!

I've been KSPing for a couple months now and, while I'm slowly accruing a decent list of accomplishment covering Mun, Minmus, Eve & Gilly, Duna & Ike, the hallowed art of docking seems to be eluding me. I've watched a plethora of youtube vids on the maneuver, I've gotten to the point where I can get 99.9% matching orbits (when I don't screw up and get perfectly matching reciprocal orbits, that is) but getting to that point where craft are sitting pretty much stand-still relative to one another and I can RCS over to dock is proving impossible for me (debris belt of failed docking attempt craft around Kerbin is approaching 200 pieces). I see many people are using mods for docking but, since I'm trying to "play it kosher" I wanted to know is it really that difficult, or am I just doing something wrong?

(I forgot: In a nutshell, I launch one vessel, circularize its orbit at 100K, launch another, circularize at 95k, wait for proximity of first one, climb to 100k and fiddle with orbitals until I'm within <1km of other craft. It is at this point that I find myself unable to do adjustments precise enough to get perfect orbital sync needed for dock...)

~Andro

Edited October 16, 2013 by Andr0s
-answered-

[Nubbe]

You have to target the other vessel, then you get navball markers for retrograde/prograde burns and just ease in to it.

[whistlehead]

Navyfish's docking alignment mod is your friend here. Best mod I've ever downloaded. (I don't count it as 'cheating'... )

Docking is one of the most difficult things in the game - you have to get your head around so many axis of movement, and sizes never quite seem right - doing it without a mod is pretty tough. I've had a few tries and it's taken hours every time... I got the mod and never looked back. I can dock pretty much anything in <10mins now, once they're close enough.

Edited October 16, 2013 by whistlehead

[Person012345]

It's not that hard. Use your instruments. The navball will switch to target mode when you get close to a target object. This will show you your prograde and retrograde relative to that object and tell you how fast you're going. It'll also tell you which direction the object is in. burn retro until you "stop" relative to it (0 m/s on the navball), burn towards it until you are going at a reasonable speed, stopping and adjusting when necessary. When you get real close use your rcs the same way. Also your method of matching up orbits seems convoluted since maneuver nodes exist.

I can pretty much go up, get an intercept within 1 orbit, then go straight in to it and dock without any difficulties.

Edit: Hold up maybe I can whip up some kind of video tutorial of my own.

Double edit: KSP decided to crash so eh. >> Plus it'll take ages to up.

Edited October 16, 2013 by Person012345

[Yalin Hawk]

Just time your launch right and you'll be able to launch right into the intercept. If it's a rocket-type launch I will launch right as the target is about to hit the ocean before the continent KSC is on. Do my normal grav turn/launch procedure, and wallah, intercept. Spaceplanes are trickier, depends on TWR and how quickly you get up to space.

For actual docking, the guy above me nailed it. Kill relative velocity as close as you can get to target. Point at target and burn. Kill relative again, repeat until you're within 100m. Then use RCS. WASD, HN, IJKL are your friends.

[klappertjes]

One tip I have from experience is that the faster you're going relative to the other craft (i.e. velocity when you have "target" selected) the harder it is to adjust what direction you're going.

So what I do is this once I hit proximity like you do:

1. Come to a very near standstill using your main engines but make sure you're still moving 'forward' (all relative of course). 0.1-0.3 m/s is preferable

2. Turn so you face the other ship (you point yourself into the pink round marker on the navball)

3. Now look at where the prograde marker is (or if you can't see it, use visual to establish what direction you're "shifting" relative to the other spaceship)

4. Use linear mode to move the prograde marker over the pink one, where Shift = up, Ctrl = down, A = left and D = right. DON'T use W and S unless you're really close and need minute changes in velocity

5. Now throttle up with your main engines to a "responsible" speed (this is experience, you'll figure it out). You'll move directly towards the ship

6. Repeat 1 through 5 as needed until you're very close (you-can-visually-see-your-target-docking-port close) and come to a standstill. Remember to allow time to turn retrograde.

7. Now basically redo 1 through 5 again, but use W and S instead of the engines.

8. Make sure your allignment is about right. The magnets will do the rest

9. Feel good about yourself

EDIT: So basically what Person said, only longer

Edited October 16, 2013 by klappertjes

[Andr0s]

@Whistlehead : Thanks for the recommendation - as I mentioned in OP, I'm trying (stubbornly and occasionally painfully) to play unmodded; I will certainly add your recommended mod to the list of "must haves" once I decide to mod up.

@Person & Yalin : Thanks! I definitely didn't know about navball mode switching, that should help massively. Also, I'll have to give the proper launch window a shot

[Yalin Hawk]

Don't worry man, you'll figure it out. It was a bear for me the first few times too, then it was like this KSPhiphany happened and I was the docking king from then on. Really play around with the RCS controls and get used to them. The translational controls, I J K L, will be what unlocks the wonderful world of docking for you.

[J.Random]

If you're able to get within 1km range, I don't understand the difficulties you're facing. At this distance you may just dump your relative velocity to 0 by pointing at relative retrograde and burning, then point at your target vessel and burn again (don't forget to a) set your target and switch your speed indicator to target mode if it didn't switch automatically), then brake while closing to it. For final approach and port alignment you may want to switch camera to Chase mode.

[Person012345]

@Whistlehead : Thanks for the recommendation - as I mentioned in OP, I'm trying (stubbornly and occasionally painfully) to play unmodded; I will certainly add your recommended mod to the list of "must haves" once I decide to mod up.

@Person & Yalin : Thanks! I definitely didn't know about navball mode switching, that should help massively. Also, I'll have to give the proper launch window a shot

The launch window thing isn't strictly necessary. If you target an object you get closest approach markers for it. So circularize the ship at the same altitude as the target, target the, er, target, and adjust a maneuver node with a prograde burn simulation until the approach markers align reasonably close.

[Meithan]

One thing that I love about this game is how acquiring new skills transform tasks that seemed initially nearly impossible to things that are routine. Docking is a great example of this.

If you can get within 1 km of the other spacecraft, half of the work is done. From here, this is what I usually do:

Step 1: Kill the relative velocity with respect to the target.

Set the other spacecraft as your target and click on the speed indicator above the navball until it reads Target. The displayed speed will now be speed relative to the target (instead of orbital or surface speed) and, more importantly, the prograde and retrograde markers will now be determined by your relative velocity vector. So, in order to kill the relative velocity between the ships, simply point towards the retrograde marker and thrust until the indicted Target speed is close to zero.

Step 2: Approach the target until you're within docking distance (~50 m is enough).

Now that your relative speed is almost zero, line up your ship with the target bearing marker (the purple circular arcs) and thrust in that direction. You'll move directly towards the target. Don't move too fast, as you'll have to slow down to a halt again when you get closer. I find that something in the range 10-20 m/s is enough to cover the ~1 km in a couple minutes (and you can time accelerate if you don't want to wait that long). Then, once you're within ~50 m, kill the relative velocity again (by thrusting towards the retrograde marker again).

It's possible that your initial thrust was not exactly in the direction of the target ship, so that your closest approach distance is larger than 50 m. If that's the case, when you see the distance to the target increasing again, stop, and repeat the process.

Step 3: Dock using RCS

Now that you're within 50 m, it's time to dock. I advise deactivating your main engines, as you don't want to mess the delicate docking approach by an accidental hit of the SHIFT key. Turn on RCS. Crucial: hit V to switch your camera to CHASE view. Without this, using the RCS translation controls is much more complicated, as the view of your ship won't intuitively match the controls.

Now place the view behind your spacecraft (assuming the docking port is in the front). It's not necessary to switch to docking mode controls. If you don't, then AWSD will still control the orientation (i.e., rotation) of your ship, while IJKL+HN will control translation: moving lef/right with J and L, up/down with I and K, and forward/backward with H and N.

Then it's just a matter of steering your spacecraft towards the docking port, making sure you're properly aligned (i.e. pointing parallel to the port). Remember that it's a 3D thing so keep checking that your alignment is correct in both the left/right axis and the up/down axis by placing the camera to one side or above/below the craft, correcting, and then returning to the back view.

One trick to facilitate docking when you're learning is to orient the target spacecraft so that the docking port points e.g. South. Then when you're in the approaching spacecraft, you'll know you're pointing parallel to the target docking port by keeping a heading due North. But honestly once you get some practice with this, you'll be able to orient and align the spacecraft simply by eyeballing it.

Hope this helps.

Edit: by the way, you'll be surprised of the strength of the magnets on the docking ports the first time you dock!

Edit2: I forgot to mention this: make sure the RCS ports on your ship are around the center of mass when you're designing it in the VAB. If they're not, then you won't be able to translate without also rotating, and that complicates things considerably. A hard lesson I learned when I was learning to dock.

Edited October 16, 2013 by Meithan

[Kosmo-not]

I don't like to boast about myself, but it's something I need to get used to if I want to land an engineering job.

I developed my method for docking (which is shown in the video below) when I heard we would be getting a "to target" marker on the navball and would be able to target docking ports (keep in mind this is before the docking update occurred). I remember yelling at Damion Rayne through my computer monitor (or whoever was attempting docking on the KSP livestream) to use the navball. Scott Manley floundered about, too, when the update was released (he has since gotten better at it, but it took him a long while).

Use the navball to help guide you in. Docking is easy!

[capi3101]

I've recently switched to using NavyFish's mod - it's made the docking process easier. Up to that point though I was doing in manually. I learned how to do it initially with the Gemini 6A and 7 tutorial over on the wiki. Got it right on the first try. The key bit is alignment. Alignment, alignment, alignment.

Here's what you do: when your distance gets to 100 meters, zero out your approach velocity. Turn off RCS and re-orient yourself to face the target (the pink meatball). Turn on SAS, switch to the target, target the initial craft and re-orient it to face the target. Turn on SAS and switch back. Turn on RCS and give it a toot ahead (H-key). When you get to 50 meters, repeat this whole process. Do it again at 20 meters. Do it again at 10 meters. Do it again at five meters if you haven't docked by then. Remember - use RCS for translation, probe torque for rotation, and shut off RCS when you want to rotate unless you've got your thrusters balanced so they don't give any unwanted translation. Once you're aligned at five, a little thrust forward should result in a solid dock.

Probably should mention that RCS is pretty much required for docking maneuvers, and you can only dock together two ports of the same size (juniors with juniors, seniors with seniors, anything else with anything else).

The launch window thing isn't strictly necessary, but it does shorten the time needed for a rendezvous. You want your target approximately 475,000 meters downrange from KSC, assuming its at about 100k in orbit.

[Kasuha]

I see many people are using mods for docking but, since I'm trying to "play it kosher" I wanted to know is it really that difficult, or am I just doing something wrong?

I am using no mods either and believe me, it's not difficult. I was able to dock ships in orbit before I was able to land on Mun without breaking the ship.

If you can get your ships close enough, all that's needed is to select the other ship as target. Once you have a target selected, the little gray rectangle with green numbers above navball telling you your speed with regards to orbit or surface gains third mode where it shows your speed relative to your target. If it doesn't switch automatically, you can switch it manually by clicking on it. Also your prograde and retrograde vectors switch to your prograde and retrograde relative to the target - so you switch your navball to target mode and by burning retrograde you stop moving relative to your target.

Edited October 16, 2013 by Kasuha

[PDCWolf]

You can also try my own docking tutorial. I tried to use a different approach.

I'll upload a commented/remade edition some day.

[Meithan]

Kosmo-not: If you're using only the magenta marker to dock, then you need to have the other craft pointing at a known direction (e.g. north/south) and your craft aligned along the opposite direction, right? Otherwise, pointing towards the magenta marker alone is not enough. The point is aligning three things on the navball: 1) your ship's attitude indicator, 2) the target's magenta marker and 3) a direction in the sky. Then you can just "dock by instruments".

[Andr0s]

Haha, you guys are ruthless with all the "it's not that hard" comments, making me feel like an utter failure

Joking aside, thanks a lot for all the advice - I can't wait to go home and try it all out. Keep your fingers crossed for me

(PS: I know Squad keeps saying "no" to multiplayer, but discussions like this make me wish KSP had a spectator mode. I can just see a drinking game where everyone watches me trying to dock, heckles over TS, and drinks every time I miss.)

[Meithan]

Haha, you guys are ruthless with all the "it's not that hard" comments, making me feel like an utter failure

We meant it as encouragement . Don't feel bad, I think it was hard for all us at the beginning. At least it was for me; my first few attempts failed miserably until I learned the technique and practiced enough. You'll see that in no time docking will be routine.

(PS: I know Squad keeps saying "no" to multiplayer, but discussions like this make me wish KSP had a spectator mode. I can just see a drinking game where everyone watches me trying to dock, heckles over TS, and drinks every time I miss.)

Then you'll be happy to know that there's a mod for that: Kerbal Live Feed. I haven't tried it myself, but it does look very cool.

[Person012345]

For what it's worth rendezvous-ing and docking by eye, without the wonders of the navball, does sound hard.

Edited October 16, 2013 by Person012345

[Lupi]

docking mode deactivates the engine and allows you to translate with W-A-S-D-Shift-Ctrl

and pressing space will toggle you from rotation to linear mode.

[Kosmo-not]

Haha, you guys are ruthless with all the "it's not that hard" comments, making me feel like an utter failure

You'll be doing the same thing, someday.

Kosmo-not: If you're using only the magenta marker to dock, then you need to have the other craft pointing at a known direction (e.g. north/south) and your craft aligned along the opposite direction, right? Otherwise, pointing towards the magenta marker alone is not enough. The point is aligning three things on the navball: 1) your ship's attitude indicator, 2) the target's magenta marker and 3) a direction in the sky. Then you can just "dock by instruments".

You didn't watch the video, did you?

[Meithan]

You didn't watch the video, did you?

I did, sir. What part did I miss?

Edit: "straight out from the docking port", I suppose?

Edited October 16, 2013 by Meithan

[MockKnizzle]

There's already two whole pages of in-depth docking guides, and who knows if you'll even read this, but damned if I'm not gonna try.

Welcome to MockKnizzle's Kwik 'n Durty Docking Guide. No mods needed.

So. Step 1: Rendezvous. We already have something up in space to dock with, right? Cool. Let's say it's in a nice, simple 100km circular equatorial orbit. Awesome. Now we're ready to launch, yeah? What we're gonna do is wait until the target is somewhere in the neighborhood of 400km out (you can see the distance to target if you hover over it in map view), make sure we have a launch vehicle with some spare dV once we hit LKO, and light that sucker.

We're gonna launch into a nice, easy circular orbit just outside the atmosphere. 75km is totally fine. Once we're up, we wanna check and see where we ended up relative to our target. Hop into map view. Our ship should be somewhere pretty close to where our target is, a little ahead or behind doesn't matter. Now, what we wanna do is find a node, either ascending or descending, and plot our rendezvous transfer there. I like to match planes first with a little purple-triangle action, and then after that, simply pull on that green prograde widget until you get a close approach (typically something less than 2km, be as precise as you want). Burn it.

Sweet deal. We're now on a rendezvous course. What now, you ask?

Step 2: Docking.

, did you see how I set that up? So slick. Well, we're now hurtling through the cosmos on a near-intercept course with our target spacecraft, but we'd really like to stop by for some tea and not zoom past at hundreds of meters per second. So what we're gonna do here is wait until we're nice and close (hopefully within the physics load distance of 2-point-something km), align ourselves with the retrograde velocity indicator cause we're already in target mode (you better be!), and burn to kill our relative velocity. Now, be careful when I say that, cause I don't mean want to stop entirely - we just need to scrub off enough relative speed that we give ourselves some time to maneuver. Docking is a continuous process, you never just stop completely.

Say we're coming in at a relative velocity of 120m/s at 2km out. We're gonna wanna slow down gradually to something more manageable, first like 50, then 20, then 10, then 5, then 1m/s. Our rate of closure is gonna depend on how far we are away, so we'll slow down more as we get closer. If you're paying attention to life and the navball, you'll probably notice that there's those nice little pink direction-to-target indicators, and also that the relative velocity indicators don't match up with them. We need to fix that.

Since we're in the process of slowing down and we're typically oriented retrograde, we'll talk about "pushing" the navball indicators around. If we thrust with our ship's nose aligned somewhere to the side of our retrograde velocity indicator (green with an X), the indicator will move away from where we're pointing. In this way, we can brake AND push that little bastard so it's more or less aligned with the target retrograde marker (pink triangle-thing). That's what we wanna do. As we close the 2km or so to our target, we want to be slowing down in a series of steps, and lining those two indicators up at the same time. In no time we'll be within a hundred or so meters of our target, and since we've been making sure the keep the velocity and target markers aligned, we're heading straight for it. Now all there is to do is find your docking port of choice, swing the ship around in that direction, and finish the job with RCS (which I'm gonna assume people know how to use).

Would you look at that, you're docked and it took less than 10 minutes to do it! Man, what a useful guide. Thanks, MockKnizzle!

Edited October 16, 2013 by MockKnizzle

[pukendog]

No, it is hard. Trying myself, futile. I have succeeded using MechJeb, but even that works 50% of the time. Good Luck.

[Rocket In My Pocket]

1 hour ago, pukendog said:

No, it is hard. Trying myself, futile. I have succeeded using MechJeb, but even that works 50% of the time. Good Luck.

Hi @pukendog and welcome to the forums!

You seem to have picked a rather old thread to respond to; none of these people are likely around anymore, sadly.

If you need help learning to dock, why not make a new thread here in the Gameplay Questions forum? Lot's of people will be glad to help you, myself included. I assure you docking stock is quite doable, although no harm in having some mods to help like Docking Port Alignment Indicator for example.

 

Edited December 13, 2017 by Rocket In My Pocket