I just can't seem to dock.

[Anizer]

So i've been having this problem for a long time.. I just cant ever dock two ships!!! I've looked at many videos and tutorials online and the proper way of docking is to get two target points that are >1 km apart while matching the other ship's orbit. This is probably as close to that as I can get:

I'm trying to dock the ship on the left to the ship on the right. They're both at approx. 150.7 thousand KM orbit and there are two closest points, at about 79km apart which does not appear on the tracking station.

I know you just burn towards the target to get closer but every time I do that my orbit is ruined and if I do not dock in time, i'll have to re-align my orbit again and fuel doesn't last forever. I've tried burning towards, then backwards to fix my orbit but then I end up losing my closest points because my orbit is now off and I also have to fix it again.

I'm not sure if there's something in this game I don't understand yet or people just get lucky. Anyways i'm getting very frustrated with this game because docking is pretty crucial to get to planets further away.

So if anyone can guide me to close that distance between my two ships that'd be great. It'd also be great if the next patch game with utilities to help guide your flight.

BTW: Both ships are travelling at about the same speed so no mater how long I time warp they'll never get closer

[rodion]

Are you aware that by clicking the relative velocity indicator (the one that usually displays surface/orbit velocity), you can change modes, including one that tells you your velocity relative to your target? That makes it easy to understand how you are moving compared to the thing you're aiming at, and additionally places the vectors on the navball so they tell you what direction you're going relative to the target too (your green pro/retrograde markers for your ship orbit, and pink markers for direction of the target). When the target velocity indicator reads 0.0m/s, you are in exactly the same orbit as the target.

Also, to close distance with an object you are attempting to dock to, you orbit should never be identical to the target's, because your relative positions will therefore stay the same forever - instead, if you need to catch up on the object, you need to drop your periapsis to a slightly lower altitude than the targets', so that for part of your orbit you are traveling faster than that target. For situations where the target is "following" you, just do the opposite, making your apoapsis slightly higher up so the target gains on you. I hope this helps a bit.

[dlmarti]

I really need a better understanding of where you are going wrong. I will assume its the approach stage only....

Do your capture, get at close as you can using the orbit window.

Switch to the regular ship display, and point your ship at the retrograde symbol.

Burn until you have 0m/s target velocity (you are selecting the other ship as a target right????).

Then point at the ship you want to dock with, its the little bluish circle symbol.

Burn until your target velocity is 1/100th of the distance to target (500m away == 5m/s, 10km away == 100m/s, etc).

Then immediately rotate your ship to point at the retrograde vector.

When you have traveled about half of the distance, burn until you have 0m/s.

repeat, repeat, repeat.

Once you get good, you can move faster, burn less, etc. For now your goal should be to get within 50-75 meters.

[Anizer]

I really need a better understanding of where you are going wrong.

I can't get an intersection point thats >1km while keeping the same orbit as the ship you want to dock to

[rodion]

I can't get an intersection point thats >1km while keeping the same orbit as the ship you want to dock to

No need to get an intersect anywhere near that precise, as long as the orbits are halfway similar it's possible to eyeball the approach just by thrusting to align the ship/target vectors from 30-50 kilometers distance. 10km or less is easiest, though.

[Rastaman]

I can't get an intersection point thats >1km while keeping the same orbit as the ship you want to dock to

Your mistake is that you keep the same orbit. You need a different orbit to overtake the target, or let yourself be overtaken by it. You create a maneuver along your path that meets the target orbit at some point. Then you drag the whole maneuver node along until the positions coincide.

When you are at the closest point, use the relative velocity indicator (click right above the nav ball to switch to relative velocity to target), and point to the "retrograde" marker. Burn to decrease rel velocity to zero. Then point towards the target and close in. Go from there.

The real challenge is to keep aligned with the target's docking port when you're meters away. Press "V" button to change to "chase" viewing mode, then place your camera behind your craft, it's much easier that way.

Docking is really really easy, provided you have a balanced spacecraft...

Edited July 27, 2013 by Rastaman

[dlmarti]

I can't get an intersection point thats >1km while keeping the same orbit as the ship you want to dock to

tbh, I CAN get an intersect closer, but I rarely bother too.

Before you do your burn to intersect, match the plane target (eye ball, anything within 20 degrees is good enough.

Do your burn, to get close.

Do another at mid course to adjust for the planes being different, or your burn being off.

Not close enough for you? Do another at 3/4 course.

Bottom line is, F5 just before you do your first burn, redo the whole thing a dozen times nice and calm.

Just chill, relax, and play with it.

After a bunch of F5/F9 attempts, you will have no problem with this stage at all. Just relax its a game, and completely doable.

Then once you have your approach/capture methods do the F5/F9 thing again and again for the getting-closer-to-target phase.

[Kegereneku]

I can give you a few tips :

first :

- Don't be afraid of modifying temporarily your orbit, because identical orbit mean no change.

second :

- If the target is ahead of you : burn retrograde to lower your orbit... and go faster (yes, even if it sound counter-intuitive)

- If the target is behind you : burn prograde to raise your orbit... and go slower

last :

- Search the "Relative Velocity marker", it will be useful

- Don't burn toward your target, unless you've first killed relative velocity less than 2km away.

Edited July 27, 2013 by Kegereneku

[Frederf]

Docking is putting two metal plates together. This is a rendezvous problem.

Your two craft look to be in very similar orbits. I bet you can get a rendezvous under 500m and kill relative velocity for under 50 m/s dV. Target the other craft and cancel relative inclination at the next node. Let's turn a 3D problem into a 2D problem.

You can think of various orbits as highways in the sky. If you need to catch a craft ahead of you you need to take the fast lane. Speed and path are the same thing. If you need a different speed then you need a different path. Targeting the destination vessel you should see 1 or 2 closest approach marker sets if your orbits cross once or twice respectively. The spread in the marker set is your projected positions at the moment your vessel crosses the target's orbit.

If the target has already passed the intersection point then you need to get there faster. Getting there faster means taking the faster path which is a lower orbit. Alternately if you arrive too soon you need to get a high/slow orbit to delay.

[MrPopcup]

what everyone said above it true, but they forgot an important thing,

NOTHING Stays near the other thing in space, they will end up very far away, so if you 'parked' your ship near the other one, time warp ahead and you'll see they'll end up separating from each other, so it's dock or not!

[dlmarti]

what everyone said above it true, but they forgot an important thing,

NOTHING Stays near the other thing in space, they will end up very far away, so if you 'parked' your ship near the other one, time warp ahead and you'll see they'll end up separating from each other, so it's dock or not!

No one mentioned anything about parking, we are trying to teach docking.

And yes, we watch Scott Manley too.

Now, for extra credit, can you prove him wrong? Because he is.

[HeadHunter67]

- If the target is ahead of you : burn retrograde to lower your orbit... and go faster (yes, even if it sound counter-intuitive)

- If the target is behind you : burn prograde to raise your orbit... and go slower

So, if the target is ahead of you, it should be above you, and if it's behind you, it should be below you?

I think I had it backwards before, but "Ahead/Above, Behind/Below" is easy to remember.

[rodion]

So, if the target is ahead of you, it should be above you, and if it's behind you, it should be below you?

That's correct. The periapsis of an orbit, as well as being the point where the orbiting object is closest to the parent body's surface, is also the point where the object's velocity relative to the parent body is highest, and for apoapsis the inverse is true, it's the slowest point in the orbit. You can try this out by time warping any ship in a non-circular orbit and watching the velocity indicator change as it goes from peri- to apo-.

[Anizer]

That's correct. The periapsis of an orbit, as well as being the point where the orbiting object is closest to the parent body's surface, is also the point where the object's velocity relative to the parent body is highest, and for apoapsis the inverse is true, it's the slowest point in the orbit. You can try this out by time warping any ship in a non-circular orbit and watching the velocity indicator change as it goes from peri- to apo-.

So I don't want to make my orbit shaped like an oval?

[Moonfrog]

I had lots of problems with docking, then I did what this other guy did on a video. In steps he sort of did this. He selected the target, then made at the ascending and descending node, he aligned himself to be at as close to 0 degrees as possible with the target. He then expanded his orbit to be twice as large as the targets to create an intercept point. The reason I like this method over some of the others, is that you are already practically in alignment with the target u just need to slow down to 0 velocity like others have said. I find this easier as, whenever I try to dock using other methods I always slowly drift away from the target no matter how much I speed towards them.

Using this method u will still overtake the target but u won't do so at a funny angle cos your be aligned so u just go back and forth. I wish I could remember the name of the video on youtube cos it was so much easier his method than scot manleys.

[Kimberly]

So I don't want to make my orbit shaped like an oval?

Sure you can; you can do this to meet a ship if apoapsis intersects with the target's orbit. But this means you'll have significant speed relative to your target, so once you're close you need to burn retrograde (relative to the target) to slow down enough to dock.

[Frederf]

This sounds like what early Gemini docking problems were encountered. If your target is on the prograde side of you then burning toward it is burning prograde into a high, slower orbit. You increase the separation instead of closing it.

The problem if your target is turning so more straight line speed isn't the answer. Ignore where the target is now and focus on where the target will be in the future and then maneuver to arrive at that time and place.

[Anizer]

Okay so lets say i'm adjusting my orbit, the best way is to burn at the apoapsis and the other point?

[iueras]

Those two points are always the most efficient, yes. You CAN change your orbit from any point, but you will use more fuel to accomplish the same change. However, if your orbit is sufficiently close to perfectly circular and is also centered on the body you are orbiting, pretty much any point on the circle will be the same.

[Moonfrog]

I found the link to the video on youtube.

. For me this is a lot easier than other peoples ideas on docking. or at least it allowed me to dock fairly easily.

[dlmarti]

Okay so lets say i'm adjusting my orbit, the best way is to burn at the apoapsis and the other point?

For what you are trying to do, it doesn't matter.

Its more important to get to your target.

[ElRageO]

I am in the same situation however I can get within 500m then everything goes wrong and I chase the other craft until I run out of fuel and burn up.

Every time I close I screw up the orbits and I usually ruin the one shot at docking. f5 and f9 help for practice so you can keep trying.

This helped me get closer Tutlink

But I cant do it consistently and its driving me nuts. If I get it figured out easily Ill post here. Hope the above link helps.

[Arkalius]

Two craft in orbit are in non-inertial reference frames. That means that if you simply accelerate one craft directly toward the other, the usual expected outcome of it eventually reaching that object, is not what will actually happen. Both of your trajectories are constantly being modified by gravity. The further apart you are from your target, the more of an effect this will have. So, in order to reach your target you have to work out the problem in a different way.

Basically, you need to modify your orbit so that the next time you reach the point where your orbit intersects your target's orbit, you are very close to it. Additionally, you want your relative speed to be within tolerances both for safety and for having a reasonable amount of time to slow down. If you're in the same exact orbit as your target, then when you modify your orbit, it will have an intersection point from the spot you modified it from. Ideally, you want to change your orbital period so you come back around to that spot at the same time your target gets there. This is where things get counter-intuitive. If your target is ahead of you, you actually want to thrust away from it, to shrink your orbit. This will shorten it's period and you will eventually catch up to your target. Conversely, if your target is behind you, you want to thrust away from it again, enlarging your orbit, lengthening its period, allowing it to catch up with you.

You don't want to change your orbit too significantly or you'll have too great a relative speed when you finally do intercept your target. When you do finally intercept your target, you'll want to nullify your relative speed to come to a near stop relative to the target while you are close by (within a handful of kilometers or closer). Then you can simply thrust toward your target to approach it. When you are this close, the complications of the non-inertial reference frame are minimized and your maneuvers will have much more intuitive results.

Don't try to rush it. The space shuttle would take a day or three to slowly sync its orbit with the space station and would take hours on the approach and docking procedures. You don't have to be that meticulous but trying to be too cowboy about it will run you out of fuel and risks damaging collisions.

[Nurph]

I am in the same situation however I can get within 500m then everything goes wrong and I chase the other craft until I run out of fuel and burn up.

Every time I close I screw up the orbits and I usually ruin the one shot at docking.

If you're within 500m, what your orbit looks like is totally irrelevant. When you're that close the only thing you should be worrying about is where your target is and how you're moving relative to it. Ignore your orbit and don't touch the map view.

[lammatt]

things to know:

Kepler's 3rd Law:

- same area = same time

- larger orbit = longer orbital period

- semi major axis ^2 is proportional to Period ^3

so... make your orbit small than your target to catch up if you are behind (and vice versa)

when they are close enough... match orbit

and then use the RCS to trim you heading and relative speed when the two approach each other (a good approaching speed would be ~0.5m/s when the tow is below 100m apart)

Edited July 29, 2013 by lammatt