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Docking, any easier way?


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Not wholly sure what you mean. I'd suggest trying NavyFish's Docking Alignment Indicator mod; it's useful whether you use Mechjeb or not.

And the usual - use RCS and make sure they're placed as far from the center of mass as possible while still being close to the same radius from the center of your rocket. Eight is good, I find twelve (a set aligned with the center of mass) aids with translation but go with your own experience on that one.

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If the ship is in front of you then get into a slightly lower orbit, otherwise get into a higher orbit and wait for it to come to you. Then just watch the separation indicator and when you see an orbit that brings you close to your target you raise your apoapsis at some point in that orbit to your targets orbital height, then when at apoapsis you should be very close to your target, circularize there and you should be moving very slowly relative to your target. Then just use RCS to move toward the target and dock.

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better solution, download mechjeb, edit part.cfg to a lower tier science ( i used stabilization). You have to go into the tech tree and "purchase" the mechjeb parts. Then you can use it in flight to autopilot to the ship you are looking to dock. lol, after 15m of trying to dock 50m away, it was time to use mechjeb and then start enjoying the game again.

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Here are the keys that made docking easy for me:

1. Build ships that are easy to dock--put the docking port on the end, not on the side.

2. Rendezvous--if you end up 50m away at .1m/s you're 90% docked.

3. Eliminate drift--point the dockee port south, point the docking port north to keep the ports from rotating while orbiting.

4. Work one axis at a time--get going toward the port, then align them vertically, then align them horizontaly.

5. GO SLOW--don't exceed .3 m/s.

6. Practice--yes, you will screw up, badly. Quicksave is your friend.

I don't recommend MechJeb as it uses an insane amount of monopropellant. I manually docked my Mun lander to an orbiter six times and only used 17 units of mono.

Don't give up hope! Docking is one of the most rewarding things in the game and will always give you a feeling of accomplishment when you do it. Good luck and let us know how it goes!

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Also when you get close to the target ship - click on it's docking port and set as target. Right click on your docking port and select "Control from here". Now you just have to put pink target marker in the middle of navball and approach it. While doing so, you will have to keep that target marker centered. Just move it using RCS controls (IJKL). Works very well for me. I never used Mechjeb and I don't understand people who can't dock without it. Its very simple. The only glitch I had was when the pink target marker was not really pointing towards a docking port. It only happened to me once, but it was not that much off, so after ships got within couple of meters, I made some adjustments to make it work. Most of the time target marker is spot on, so no adjustment is needed. Keeping it centered on navball is enough. It works so well that I have no trouble docking in the dark.

Docking ports have to be pointing towards each other though. Easiest way to achieve that - switch to a target ship, mark approaching ship as a target ant point your docking port towards it.

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Finally I found my own way of docking. I never get the angles right.

1. Collide the docking ports at about 0.5m precision at about 0.2m/s speed. The angle still has to be at least 45deg.

2. Gently rotate to the required direction till you are docked. Magnet of the docking port holds one end of the ship in place.

Now I can dock an average sized ship even without a monopropellant.

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Rendezvous - not particularly difficult. Here's the short version -

1) Target the other craft on the map screen (click on it and select "Set As Target"). You may need to turn on filtering if there are a lot of other objects in and around its orbit. I find zooming in on it sometimes helps.

2) Look for two chevrons that appear marked AN and DN - these are the ascending node and descending node, respectively.

3) Assuming you're in an eastward orbit (prograde heading 090), you want to burn northward (000) at the descending node or southward (180) at the ascending node, whichever you come to first, until it reads 0.0 or NaN.

3A) If you get it to NaN, you're dead on - there's so little variation in the plane of your orbit that the programming language KSP uses can't distinguish any difference.

4) Now, find the little intersect chevrons - these tell you how close you'll approach the target. Set a maneuver node at periapsis and gently pull prograde. Watch what happens to the distance.

4A) If the distance decreases, keep pulling prograde until the distance starts to increase.

4B) If the distance increases, pull retrograde instead. Keep pulling until the distance starts to increase or until your resultant periapsis would be lower than 70,000.

5) Make the indicated burn. Use RCS prograde/retrograde (H and N keys, respectively) to correct if necessary.

6) Same thing, except this time do it at periapsis.

7) Repeat the process at the apses until you're not getting any more appreciable results.

7A) A rendezvous will occur if your closest approach is within 2,250 m.

8) If you're not getting a rendezvous, try the same method, but at a point roughly midway between the apses. These should be short burns.

The alternative, of course, is to set up a long, hard burn at your periapsis once your planes are aligned such that you wind up setting a resonance with the target - you go wide, it makes several orbits in the time it takes your craft to make a single orbit and you wind up passing very close to one another. You make another hard burn to slow down your relative velocity. This method works, but it consumes a fair amount of delta-V in the process. Can't really recommend it for Kerbin, though I've had success with it over Mün and Minmus before.

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it was time to use mechjeb and then start enjoying the game again.

Fair enough, but pay attention to what Mechjeb is doing, particularly how it breaks rendezvous down into stages. It also has a semi-automated "rendezvous planner" instead of the rendezvous autopilot that lets you take over some of the work. For the final docking itself, you'll find Mechjeb will get the job done, but frankly it sucks and will use heeeaaaps of RCS fuel. Design your ships with plenty. When you're ready to take over you'll find you'll be able to do it using far less RCS fuel, which will make for smaller, lighter, better ships.

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Docking is the first main hurdle in KSP and gets most people screaming "WHAT THE *BLLLLLEEEEEP* IS GOING ON NOW?". I could never figure out that my relative velocity was easily figured out by selecting the target you want to rendezvous with and then clicking above the nav ball until it shows "Target". It will then show the relative speed between your craft and the target. Then it was easy to follow Scott Manley's tutorial regarding docking.

This is from 0.18 but is pretty much the same now...

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BTW, use nodes only to get intercept course to target. So you set up nodes to have closest approach like 5 km (the less the better, especially on low orbit or when close to atmosphere; watch your orbit during these maneuvers in order not to get into atmosphere while trying to approach target). Then switch navball to target mode and watch relative speed it shows. When you're in about 30-40 sec to closes approach, find retrograde marker (in "target" mode!!! it won't be orbital retrograde, it'll be retrograde relative to target in that case) on navball and make a burn till target relative speed is 0-1 m/s (you'll brake relative to target and also match your orbit - watch map view to see it). Then point towards pink prograde marker and make a burn so taht your green prograde marker matches it (don't speed up too much, 20-30 m/s is enough). Your closest approach on map should be much closer now. Get close to it and repeat braking process. When your in 50-100 m from target - drop your relative speed, switch to control from docking port, target needed docking port and use RCS from now on. I prefer docking mode because I'm more used to WSAD than to IJKL. Now it's better to look at navball only, because if you have symmetrical round rockets to dock, it'll be hard to guess where is "up" and where is "down", navball eliminates that problem. For docking procedure it was already written above.

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Just one tip that i find usefull.

After the rendezvous burn is done, switch to target speed.

When you get near the "closest approach" point of orbit, aim retrograde on that node and kill all relative speed.

You will usually be between 20 or 3km (you will get closer with training).

From now, stay on ship view, you don't need map view anymore, its easier this way.

Then, aim towards your target and burn to have no more than 30m/s relative speed

Right after the burn, turn your ship towards the retrograde relative speed movement.

When you get closer to the target (you will likely undershoot/overshoot) burn to kill relative speed to 0 again.

Then use RCS to aim them towards each other or north/south, space/ground and use RCS to accelerate towards it.

Another tip:

Target the docking port you want, then set your port at "control from here".

You don't need docking mode, the prograde marker will drift away from the target you correct it using IJKL!

Then only worry about keeping the prograde at the target and use H/N to control approach speed.

Disable SAS and RCS of both crafts when the docking ports are close, otherwise the SAS will fight against the port force.

EDIT: Explaining IJKL correction better:

When docking, you will use H to go towards the target.

If the prograde marker of the navball starts to go away from the target marker, using IJKL will move your prograde speed around without having to spin the craft.

Try it, it's really easy.

Edited by tetryds
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Just one tip that i find usefull.

After the rendezvous burn is done, switch to target speed.

When you get near the "closest approach" point of orbit, aim retrograde on that node and kill all relative speed.

Just for clarity, you burn retrograde at the target's retrograde velocity marker, which looks like the typical green circle + 3 lines retro marker, not the pink markers. Relative velocity is the velocity listed when the reading says "Target". The goal should be to have the target's relative prograde marker (yellow) right on top of the target direction marker (Pink Bullseye).

Also the "Translational Controls" (IJKL & HN) only work with RCS, and you have to have RCS appropriately positioned to thrust on an axis.

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Also the "Translational Controls" (IJKL & HN) only work with RCS, and you have to have RCS appropriately positioned to thrust on an axis.

Yeah forgot to mention that you need RCS.

At least on your first docking trials, make sure you have plenety of RCS.

After you master it, you won't need more than 40 (liters?), if you even need it at all.

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Yeah forgot to mention that you need RCS.

At least on your first docking trials, make sure you have plenety of RCS.

After you master it, you won't need more than 40 (liters?), if you even need it at all.

All depends on the payload, objects size and number of RCS ports, its locations and the total weight. Many factors. 40 liters don't last long when I dock +100t payloads.

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