Why can't i dock?!

[shoveycat]

I can make beautiful planes that can circumnavigate over and over again, i can land all both moons with fuel to spare, but i can not, for the life of me, dock to craft together, and that's what i feel is holding be back from going to other planets. After watching Scott Manley's video, i followed it step by step, and i always end up burning retrograde to slow down my orbit, which, by the way is nearly 2,000 MPS and i watch the craft i want to dock to fly right overhead, if anyone has any idea at all what the problem may be, please for the love of all that is Kerbal, give a suggestion, if i dont get anythig that works, i'll probably post a video of my attempt. Thank's for any help.

[rryy]

Durrrr. I didn't fully read the OP and this post is completely irrelevant.

Edited July 7, 2013 by rryy
Derp.

[Flixxbeatz]

Watch. No info overload. Easy to digest. Quick video.

[K^2]

You need to burn retrograde with respect to target velocity. Make sure that the little word before the orbital velocity indicator says "Target," rather than "Orbit" or "Surface". You can click that indicator to cycle through these.

[Johnno]

Once you've matched orbits to get an encounter (anything really, be it 1km or 15km) click the speed readout on top of your navball, click it until it reads Target. That's your velocity vs your target (which you should have selected from making the orbit adjustments). When you get close burn retrograde until it's near zero. Turn to face your target, burn straight towards it. Look at your map and see where the next closest encounter is, wait for it then burn retrograde again to nullify your speed vs target. Burn toward target, rinse repeat.

Depending on distance to target I personally only burn so I'm going about 10-15 m/s. All depends on what engines you have, how much fuel, how slow and safe you want to take it, etc. I enjoy slow dockings.

[K3n]

ok, I personally think that docking is the hardest thing to do, yet all you need is practice. To dock, you need both your instincts and experience. Ok first, try to get a close encounter, always as close as you can. 20km to 15km=good, 15km to 10km= better, 10 to 3= best, 3km to #m= way too close. so after you get an encounter you like (id recommend like 10 km to practice)

kill your relative velocity to the target (burn retrograde till the green number above the nav ball keep decreasing until you are close to 0, if it starts increasing after reaching a certain number, that's your permanent speed until you get closer and don't worry, it will decrease later.) Now start burning towards your target, i always do it with only RCS, cuz my ships are too large to rotate, but you have to choose wisely, if you gain too much speed, you can crash into it or plainly miss it, so its better slow and steady. What i do is thrust for a few second so the distance decreases, and when the distance starts increasing, i repeat the process. Its pretty slow, but it works, and quick save regularly. After doing that for a while, get as close as you can to the ship without touching it, and with SAS keep the ship steady, next switch to the other and make that ship's docking port face the other docking port. Next, carefully use translation controls to start to align the docking ports. always remember to keep you ship steady( meaning when you burn one way, you have to burn the opposite to stop)and then slowly dock, and turn off your SAS as soon as you make contact. The ships should become one. hope this helps

[shoveycat]

Once you've matched orbits to get an encounter (anything really, be it 1km or 15km) click the speed readout on top of your navball, click it until it reads Target. That's your velocity vs your target (which you should have selected from making the orbit adjustments). When you get close burn retrograde until it's near zero. Turn to face your target, burn straight towards it. Look at your map and see where the next closest encounter is, wait for it then burn retrograde again to nullify your speed vs target. Burn toward target, rinse repeat.

Depending on distance to target I personally only burn so I'm going about 10-15 m/s. All depends on what engines you have, how much fuel, how slow and safe you want to take it, etc. I enjoy slow dockings.

Been doing it word for word, still, for the life of me, can't do it, ill try and post a video tommorow

[Mr Shifty]

When you get close burn retrograde until it's near zero. Turn to face your target, burn straight towards it. Look at your map and see where the next closest encounter is, wait for it then burn retrograde again to nullify your speed vs target. Burn toward target, rinse repeat. .

I'm curious how much efficiency you lose using this method vice "pushing" or "pulling" your pro- and retro-grade markers onto the respective target markers on the NavBall. (Probably not much.) Once I get within about 30 km of the target vessel, I never go back to the map screen until I've docked. And I never slow down to 0 m/s relative until I'm within about 30 meters and ready to use RCS.

[Sirrobert]

I can make beautiful planes that can circumnavigate over and over again, i can land all both moons with fuel to spare, but i can not, for the life of me, dock to craft together, and that's what i feel is holding be back from going to other planets. After watching Scott Manley's video, i followed it step by step, and i always end up burning retrograde to slow down my orbit, which, by the way is nearly 2,000 MPS and i watch the craft i want to dock to fly right overhead, if anyone has any idea at all what the problem may be, please for the love of all that is Kerbal, give a suggestion, if i dont get anythig that works, i'll probably post a video of my attempt. Thank's for any help.

If you somehow see 2000m/s, than you are NOT in target mode, but in orbit mode

[Nibb31]

I can make beautiful planes that can circumnavigate over and over again, i can land all both moons with fuel to spare, but i can not, for the life of me, dock to craft together, and that's what i feel is holding be back from going to other planets. After watching Scott Manley's video, i followed it step by step, and i always end up burning retrograde to slow down my orbit, which, by the way is nearly 2,000 MPS and i watch the craft i want to dock to fly right overhead, if anyone has any idea at all what the problem may be, please for the love of all that is Kerbal, give a suggestion, if i dont get anythig that works, i'll probably post a video of my attempt. Thank's for any help.

It sounds like you problem is with rendezvous, not with docking.

It also sounds like you have a misunderstanding about what the navball is telling you, and maybe a confusion about the pink and yellow markers.

When you are trying to rendezvous with a target, you need to have selected the target in map mode, and the navball must be indicating Target. This means that the speed indicator and the yellow prograde and retrograde markers are now indicating your relative speed to the target. Any manoeuvers that you perform with regards to those markers, in Target mode, are relative to the target (and not your orbit). The pink markers indicate the direction of your target. Only the pink positive direction is useful. The pink opposite direction serves no real purpose. Rendezvous is all about getting close to the target by burning towards the target (the pink target marker), and then reducing your relative speed to zero by burning opposite to your velocity vector (the yellow retrograde marker). When your relative speed is zero, you will be on the same orbit as the target, and therefore stationary. From that point, you can gently thrust around the target with RCS, just like you would in EVA, and get yourself in position to dock.

To rendezvous, this is how you do it:

1- Select your target in map mode. Click the navball where it says Surface or Orbit to switch it to Target.

2- Place yourself in an orbit that is lower or higher than your target. This is important, because if you are at the same altitude, it will take ages to catch up (or be caught up) with your target.

3- Set up a manoeuver node that intercepts your targets orbit. This is the tricky bit, because there is a lot of trial and error involved with pulling the handles around. Aim for a distance that is below 2km from the target. The closer the better.

4- Execute your manoeuver mode and watch your ship reach the closest approach distance.

5- Make sure your navball is in Target mode. When your ship gets to your closest approach distance, point to your retrograde marker (which now indicates your vector relative to the target), and burn until your speed is 0.0m/s.

That's it, you have achieved rendezvous.

However, you might be a bit too far away from your target to go for a final docking approach. To manoeuver closer to the target, this is how you do it:

1- With a relative speed of 0.0m/s Make sure the navball is still in Target mode. Point your ship towards the pink marker. This indicates the direction to your target.

2- Burn gently towards the pink marker. Do not exceed 2 or 3m/s. The (relative) prograde marker should come close to that pink marker.

3- If you start going too fast, or as your prograde marker drifts away (this is normal), just point retrograde and cut your speed to 0.0.

4- Repeat steps 2 and 3 until your distance is below 500m.

Finally, you want to approach your target and dock with RCS only. This is how you do it.

1- With your two ships stationary to each other, switch to your target ship.

2- Point it in a particular direction (Normal/antinormal or "North/South" is often suggested, but not mandatory). Switch on ASAS.

3- Switch to your docking vehicle, point it so that the docking port is in the opposite direction. Switch on ASAS.

4- Switch on RCS, let the ASAS handle the WASD keys and concentrate on translating with the IJKLHN keys.

5- Watch your navball as you align with the target. When both ships are pointing towards each other, the pink marker should be in the middle of your navball.

6- When everything is lined up, you can thrust towards the target with H. Don't go too fast, and try to keep the yellow prograde marker and the pink marker in the middle of your navball.

Edited July 8, 2013 by Nibb31

[Mr Shifty]

The pink markers indicate the direction of your target. Only the pink positive direction is useful. The pink opposite direction serves no real purpose.

It depends what kind of rendezvous you are doing. If you're doing the stop-burn-stop method you describe, you don't use it much. But when I rendezvous, I don't kill my relative velocity until I'm within 30 meters of the target. I just use my engines to adjust the direction of my velocity vector so it's pointing toward the target. Usually, this involves burning retrograde (relative) so I use the anti-target marker far more than the pro-target one.

[shoveycat]

Got right, dead next to it....... ran out of god**** monopropellant...

Edit: Tried it again, just, can not do it, do you think trying to burn for it earlier would be a good idea, since it always zips right over me

Edited July 8, 2013 by shoveycat

[Flixxbeatz]

Got right, dead next to it....... ran out of god**** monopropellant...

...and this is why I bring more fuel than what I'm actually needing...

[Mr Shifty]

Got right, dead next to it....... ran out of god**** monopropellant...

Edit: Tried it again, just, can not do it, do you think trying to burn for it earlier would be a good idea, since it always zips right over me

Can you post a video, or at least some screenshots? It's hard to help you out if we can't see what is it you're doing. Is your craft hard to turn? If not, you shouldn't be using RCS until you're really close to the target vessel (like 30 meters away.) Note also that using RCS and ASAS together will deplete your mono supply really fast. ASAS is a terrible control system for reaction control.

[shoveycat]

I'll try to post a video tommorow, but no, my craft is is small and easy to turn without RCS, in orbit, that is, and i dont use ASAS and RCS together, the problem is that it depletes the monopropelant from my lander stage (what im trying to dock) before the monopropellant in my launch and transfer stage, although, with some wings and controll surfaces, if managed to almost entirely cut out RCS usage before orbit

[Nibb31]

Do all your approach without RCS. You should only need RCS for the final docking approach, when you are under 500m from the target. Also, don't go too fast. Going slow and taking your time saves propellant.

If you are trying to dock a large multi-stage vehicle, then you are doing it wrong. You should learn the ropes with two dedicated 'Gemini-style' spacecraft, small with lots of monopropellant. If one runs out of propellant, switch to the other one. Do this a couple of times until you've learned the basics. Then you can go for your refueling station or whatever you are trying to do.

[TMS]

I'll try to post a video tommorow, but no, my craft is is small and easy to turn without RCS, in orbit, that is, and i dont use ASAS and RCS together, the problem is that it depletes the monopropelant from my lander stage (what im trying to dock) before the monopropellant in my launch and transfer stage, although, with some wings and controll surfaces, if managed to almost entirely cut out RCS usage before orbit

You shouldn't need RCS on a launch stage, unless its a horribly large, inelegant and unbalanced monster.

[Budabacon]

I understand perfectly what you mean when you say that it passes you by very fast, i was once almost 30 min, chasing and passing by for my spacestation, trying to dock, but i figured i was having a problem with my orbit and my speed relative to my target, once thats fixed, its easy pie, now im facing a diferent problem, i dont have the target icon in space relative to my docking target, my last dockings were made visually, its not so easy but the pleasure is greater eheheh, i mean i actually have to search my target in freaking space, even when my navball is in target mode and im really near my target (500m or less), i dont have that yellow rotating aimsigth on the target. Maybe im missing something, dont know.

Either way, my reply to this post is to try an help you,i am by no means an expert on KSP, ive been to the Mun a couple of times and i've only docked just a handfull of times, but i did it heheh, i can give you my skype adress and show you how to do it if you want, it's andre.p.martinho in Montijo - Portugal, i have helped a couple of my friends this way its easier because we can talk and i can show you sharing screens how to do it. I'll try to be logged on tonigh, if you want give me a call.

Happy launches everyone...

[shoveycat]

You shouldn't need RCS on a launch stage, unless its a horribly large, inelegant and unbalanced monster.

Its not the most responsive to the gravity turn

[DROWNINGMONKEY]

You can always wack multiple normal SAS modules on the launch stage to keep your ship steady just in case you didn't know that ASAS and SAS are different and that multiple SAS units can be used together to be like one mega SAS.

[Nibb31]

Make sure you are using gimballed engines. You shouldn't be wasting RCS on launch.

[vincespeedmk2]

I know someone's already posted a set of instructions but here's. 4 stage method I use to make quick rendezvous. (Usually 2-3 orbits):

1) get into orbit.

Obvious but essential. The trick is to launch when your target is a quarter of an orbit behind the ksc. That way you end up ahead of it. Make sure your apoapsis touches. The target's orbit before you complete. Circularisation.

2) match orbital inclination:

In map mode. Set the vehicle/station you want to dock with as the target.

Find the nearest ascending/ descending node and set manouver node there. You will have to burn north/south to match inclinations. You will know when this is done because the ascending/descending nodes will read 0.0.

3) rendezvous cousin. Pick one of the pairs of intersect markers (orange or purple). Burn prograde slowly, you should find that the intersect markers begin to move towards one another. Continue to burn until they match up by eye. Then use rcs/ careful burns to fine tune until the target separation is as low as you can get it. If you practice a lot you can regularly make it 0.0km, the perfect intercept. You may want to turn retrograde at this point. And time warp until just before your rendezvous.

4) docking.

As you approach target, you may want to decelerate. As a rule set a speed limit of no higher than 20mps within 2.5km of the station.

When you get to 100 m slow right down to 5mps or less. At 30 meters you want to be right down to 1 mps. Right click your docking port and control from here. Select a docking port and line yourself up by eye. Then engage the asas and rcs. Use the translat keys "IJKL" to fine tune your approach and before you know it. Robert is your cousins dad and you sir/Madame are docked.

Edited July 9, 2013 by vincespeedmk2
Spelling error

[CleverClothe]

When your relative speed is zero, you will be on the same orbit as the target, and therefore stationary.

Great post, but one minor thing. This sentence is not true. Since orbits are round, the only way you could have zero relative velocity and be on the same orbit as your target is if you were directly inside your target. If you have zero relative velocity, then you are on a slightly different orbit and will drift over time.

Orbits being round is also why burning strait at your target from a distance away wont quite get you exactly at your target.

[Klingon Admiral]

Select a docking port and line yourself up by eye.

Or align your docking ports torwards the normal/anti-normal vectors of your orbital plane for an easy way to get almost perfect alignment.

[GROOV3ST3R]

I find that using Kerbal Engineer Redux with Flight Engineer makes this a whole lot easier since it tells you the exact speed difference between you and your target as well as the distance. I think it's a great little tool to have

If you want to dock without it, all you need to do is match the speeds and orbits together and once you are on roughly the same orbit as your target, you can start to close the gap. It is a LOT easier to do with RCS than engines but not impossible without. Also, beware of the inertia that your modules have, you don't want to hit the station and send it into a spin, wasting time and having to catch it again.