djr5899

Any veteran tips for the docking inept?

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Different day, same recent topic for me.   Docking vessels together is going to be the death of me or cause me to set fire to my PC in frustration.  There has GOT to be a better way, without having a mod just do it for you.  There is just so much to do in this game that I haven't even scratched the surface of yet.  Never been successfully to a planet outside of Kerbin realm of  Kerbin, Minmus, and the Mun, and I feel it is because I can't dock for nothing.

What typically happens for me is that I can get my two vessels within around 50 meters apart from each other, and then it just seems like I play an endless game of having the one vessel fly around/by/past the other vessel that is in orbit.  I've been using docking port mod, and even with that I've noticed some issues, like it not being able to identify Rockomax Hubmax multi-point connectors (do those things need need docking ports placed on them to have Dock Port Indicator mod see them....hope not), and occassionally seeing my the front of my ship (where the docking port is) act like the back of my ship, meaning the orange doc alignment circle doesn't show up properly.

This guy just wants to build a simple space station about 250Km out from Kerbin.  I sent my Habitation module up first, and followed it off with my Science module. I spent 3-4 hours yesterday failing at docking the two pieces.  The main issue to me seemed to be even though I built my RCS thrusters as evenly spaced out from center of mass as possible, when using the thrusters, they still seemed to drift off course and not respond true to the inputs given. By some miracle, coming back to the game after a 2 hours break I managed to get my Science mod lined up,  speed down to 0 m/s, and guide it in and docked.  Figured, ok, maybe now I got it.  Sent out my last pieces, combined fuel station module as well as escape pod. Nope.....not happening.  Here I am again spending 2-3 hours this afternoon trying to get the damn things docked, and it just is not happening.  Biggest problem now is that I want to dock to the Rockomax multiport connector, and Docking module won't recognize it....but even then, I am stuck in the endless dance of getting close and then having the orbiting piece fly right by me.

If anyone has any other tips for a frustrated guy running 1.4.3 in accomplishing any of this, I'd appreciate it.  I was in this same boat over a month ago.  I really want to enjoy this game, but my inability and inefficiency in docking is sapping  the enjoyment.  I can't keep spending hours upon hours playing, doing the same thing, with no progress at the end of those several hours.  :(

  • Building vessels with RCS thrusters spaced properly to get proper movements without drifting.
  • Is there a way to make STS movement to defined markers (Target, prograde, retrograde, etc) move fast without turning on engines?   When you have a larger vessel to try and dock, it moves so slow or won't move at all without thrusters.  Would adding more reaction wheels help that?
  • Does Rockomax Hubmax multi point connect need docking ports placed on them to dock?  Or to have Docking Port mod identify them?
  • Tips on how to avoid getting in pattern of having orbiting object you are trying to dock continually get within 50m only to start drifting away from you?
  • Any tips on camera setting to use?  I constantly feel like I am adjusting the camera, or getting it stuck at the point where it won't spin one direction anymore.
  • Any mods that will dock for you once you get to a certain distance away?

 

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Building vessels with RCS thrusters spaced properly to get proper movements without drifting. 

Not just you. This is a common design challenge. 

Quote

Does Rockomax Hubmax multi point connect need docking ports placed on them to dock?  

Yes. It has places for docking rings but you need to add the rings. 

Quote

Tips on how to avoid getting in pattern of having orbiting object you are trying to dock continually get within 50m only to start drifting away from you? 

No tips, that's just how orbits work. It sounds like the problem you might be having is approaching too slowly, allowing time for small velocity divergences to build up. 

Quote

Any tips on camera setting to use?  I constantly feel like I am adjusting the camera... 

Also just part of the process, though for the final approach I usually switch to "locked" mode along the axis of the ship I'm steering. 

Can't help you with the mod questions, since I don't use them. :)

You might try practicing with smaller ships. Here's a trainer I made a while back. 

https://kerbalx.com/Vanamonde/M131-Docking-Trainer 

The handy thing is that the ships all take off together, so you don't need to fly a rendezvous first. 

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Posted (edited)
49 minutes ago, djr5899 said:

Any mods that will dock for you once you get to a certain distance away?

Yes, Mechjeb will do it - but:

This is simply me sharing a viewpoint, not trying to cocerce you into doing or not doing something. 

I believe that by having a mod dock for you, you're doing yourself a disservice.  It is (by my opinion, and many others') the most difficult thing to do in this game.  It's frustrating, confusing, and it will have you pulling your hair out.  Until you get it, that is.  There's a bit of advice, a video, some other kind of tutorial out there that will finally relate and make you get it.  And there's nothing quite like the first time you manage to dock.  Even better than the first time you get to orbit.  Once you get it, it will be second nature in no time.  I was once in your shoes, now I'm assembling space stations with shuttles.  I would not feel as awesome about that as I do if I was having a mod do it for me.  Plus Mechjeb can get it wrong was worse than you are now.

I know you have a lot of time in the effort already, I just believe it's worth the payoff.  Just a thought :)

49 minutes ago, djr5899 said:

The main issue to me seemed to be even though I built my RCS thrusters as evenly spaced out from center of mass as possible, when using the thrusters, they still seemed to drift off course and not respond true to the inputs given

This seems like a common issue with trying to control the craft based on actually looking at the ship.  "Up" isn't necessarily "Up".  When using [IJKL] to control the RCS translation, you want to focus on the navball.

Once you get your two ships close (say, less than 200m apart), you'll want to stop by killing relative velocity.  Seems you already have that part down.

Next you'll want to point them at each other.  Make sure your "control from here" points on both ships are set to the docking ports you're planning to dock.  Once that's done, assure your SAS is on stability assist on your target, and that your SAS is set to target on your docking ship.  Make sure your navball is in target mode (which it should be already, but always double check)

Puff forward with your RCS using [H].  Don't go too quick, make sure you have enough time to slow down using [N] to less than 1 m/s for docking, but don't lollygag either, or the drifting will be a problem.

Use [IJKL] to keep everything lined up.  You want to keep your Target:targetpro: and Prograde :prograde: markers lined up.  With SAS on target mode, your :targetpro: will stay put, just make fine adjustments using [IJKL] to keep :prograde: on top of it.

Edited by Geonovast
Apparently [ I ] without the spaces makes everything italic...
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I've used MechJeb as an aid for docking for years, primarily to keep my ships aligned in a given orientation to simplify the alignment process. Other than that, it's just a skill that you have to practice.

Also, try the RCSBuildAid mod. It'll help you place the thrusters in a balanced configuration. That solves a LOT of headaches.

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Posted (edited)
1 hour ago, Geonovast said:

I believe that by having a mod dock for you, you're doing yourself a disservice.

Until you get the hang of it.  I use MJ routinely for docking, but I keep an eye out for it having issues.  If it seems to be having trouble, then I'll step in and take over those more complicated dockings.  I do some many dockings, it has become cumbersome to do them all manually. 

 

I do use a docking alignment mod to help me dock, Docking alignment Indicator.  Helps me get lined up quickly and effeciently.   Really helps with the keeping "up" as "up". 

 

There's also:

Just depends on how you like the GUI. 

Edited by Gargamel
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11 minutes ago, Gargamel said:

Until you get the hang of it.

Agreed.  Once it becomes routine, then I don't see an issue handing it over.  I'm as nervous as Jean-Luc Picard when it comes to handing control of my ships over to the computer.

It's like driving a stick.  You don't have to be good at it or like it, but you should know how to do it.

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A big tip is to make sure each vessel is pointed along the same axis - most people like Normal/Antinormal since they don't drift - before docking. Just use SAS to hold that position on both craft, and the biggest problem - orientation - is solved.

As previously mentioned, use the navball. "Eyeballing it" doesn't work for docking.

Use the more delicate control mode by hitting Caps lock; it makes fine maneuvering easier.

When building your craft, use reaction wheels only for torque, no RCS. Go to each RCS port, and go to show actuation toggles, then turn off pitch, roll, and yaw. If you don't, your thrust will make you spin, and then the counterspin will make you thrust. It's maddening.

 

Here's a step-by-step guide that should work, as long as you keep the craft simple (IE, attach them end-to-end, not side-by-side).

1) Assuming you've rendezvoused, make sure you've set your target to the docking port - not the vessel -  by double-clicking it.

2) Tell your ship to hold Normal orientation, and the mating ship to hold Antinormal.

3) Back up your ship until the target indicator can be clearly seen on the navball.

4) Using the navball, translate your ship until the target marker is aligned on either the vertical or horizontal axis.

5) Repeat the same for the other axis.

6) Move forward cautiously; 1-3 metres per second is plenty. Watch the navball closely, and gently correct any drift with small puffs of RCS. Again, make sure you've hit caps lock for fine control here.

7) On final approach, slow down to ~1 metre per second, or less. Disable SAS, and drift in while still correcting any last-minute drift.

 

That's by no means the fastest way, or the most efficient, but it should be reliable.
As with all things in KSP, (and life) practice is key. Just like orbital maneuvers, rendezvous, intercepts and landings, things may not seem intuitive at first, but as you gain more experience you'll gain an instinctive sense of how to dock. It opens up a whole new world, so stick with it!

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Posted (edited)

Pro tip: Since it's hard to perfectly balance RCS, especially when the CoM moves as fuel is burned, you can press CAPSLOCK for 'fine control.' This reduces RCS thrust and seems to balance it, as long as it's not wildly unbalanced. Also, it is easier to control a smaller ship and takes less propellants to maneuver it. So dock with the smallest ship, unless impractical for some reason

I'm a fan of the NavBall-DAL mentioned above, as it doesn't take anymore screen space. The only downside to that is the :prograde: marker disappears if' your closing velocity is zero, so it's hard to tell which way you're drifting (NF-DAL will tell you in that instance. So the trick is,to keep closing.

At about 90-100m, get your closing velocity close to zero (say, 0.5m/s or so, or whatever you're comfortable with), then select the desired docking port as target. Switching ships back and forth with [ and ] can make this easier. Switch to target ship and rt-click the docking port you want, select control from here, and point it (if you're not trying to dock with a massive unwieldy station) at the approaching ship while leaving the Part Action Window open; then switch back to the approaching craft, and  you can select 'set as target' in the PAW you just opened. Now, the only thing you really need to look at from this point on is the Navball. Point your approaching craft at the red circle that just appeared in the navball, and "herd" the target marker to the red circle with the :prograde: marker, as shown in the handy-dandy graphic below. Slow as needed when you get closer; I usually make contact between 0.1-0.3 m/s

kQKWpun.png

Edited by StrandedonEarth
corrected neuroflatulence
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5 hours ago, djr5899 said:
  • Building vessels with RCS thrusters spaced properly to get proper movements without drifting.
  • Is there a way to make STS movement to defined markers (Target, prograde, retrograde, etc) move fast without turning on engines?   When you have a larger vessel to try and dock, it moves so slow or won't move at all without thrusters.  Would adding more reaction wheels help that?
  • Does Rockomax Hubmax multi point connect need docking ports placed on them to dock?  Or to have Docking Port mod identify them?
  • Tips on how to avoid getting in pattern of having orbiting object you are trying to dock continually get within 50m only to start drifting away from you?
  • Any tips on camera setting to use?  I constantly feel like I am adjusting the camera, or getting it stuck at the point where it won't spin one direction anymore.
  • Any mods that will dock for you once you get to a certain distance away?

I know what usually works for me, so maybe it will help you also... mind you however, I'm playing v1.2.2 .....

Building; I try to keep the SAS/ASAS (reaction wheels) unit near the center of mass of my ship. Doing this, my ship building is done in stages, because as you build up the ship the center of mass will change... but in the end, I want my final 'stage' to be balanced, because that's the one I'll be driving and docking. Along with the SAS/ASAS unit, I also work the RCS blocks similarly with 4x symmetry fore and aft of the center of mass.

Reaction wheels & movement; That's all going to depend on your build, it's size and mass, and the power and placement of the SAS/ASAS unit(s). If you have a really big craft, I don't think you'll want to be swinging it around 'fast'... leave yourself time and distance for such maneuvers.

The Rockomax Hubmax; As Vanamonde explained above.

Mods that dock for you; I don't use them... never have, never will. Do feel free to try what's out there however - whatever works for you and makes your game fun.

Camera; Again, as Vanamonde suggested, and others. I myself use the Hullcam VDS Continued mod, I love its docking camera (and nightvision camera). For me, along with the NavBall for reference, docking is just like driving / piloting the vessel while looking through the viewport of the docking port... my docking is very controlled, at ease, and a breeze.

 

As for getting into positon; Sounds like you know how to make an intercept no problem. Just make sure that at the end of your intercept burn, you've nulled out your velocity relative to your target before attempting to fly over to it. And when you do fly over to it, take it easy... you don't want to get right on top of it and suddenly need a full throttle burn to stop lest crashing into it - and even if you don't crash into it, your exhaust plume could actually cause the target to drift if you're too close.

When you initially select your target, it's the ship/station in general (like its center of mass, or its command module), whatever, it's not your intended goal in the end. So, when you're within 150m of the target, you should be able to select your destination docking port... right-click on it and 'set as target'. Also, you'll want to right-click on the docking port of the vessel you're driving which you intend to dock with... select 'control from here'.

Now, however it is you end up choosing to pilot your vessel in, all lined up proper on approach... my advice is to come in slowly. When you're moving a lot of mass around, there are consequences should you collide (dock too hard). I myself, when I'm about 10m ~ 20m out, I insure my forward velocity is reduced to about 0.5m/s. As I close in, when I'm pretty much right on top of the docking collar, about 2m out, I have forward velocity reduced to 0.1m/s... at this point, about 1m apart, the magnetics of the docking ports will grab hold of each other and pull gently in together. If you're viewing through the docking port (using the Hullcam VDS docking camera), you'll see the docking collar light up when the magnetics kick in; At this point, immediately turn SAS/ASAS off and RCS off... and for any other method you're using, make sure they're off before contact is made. With the magnetics working, even if you're not spot-on in alignment, the two docking ports will bump uglies until both vessels settle in and connect... it might take a few moments or so, but they will.

 

Good luck! :cool:

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Posted (edited)
9 hours ago, strigon said:

Use the more delicate control mode by hitting Caps lock; it makes fine maneuvering easier.

 

6 hours ago, StrandedonEarth said:

Pro tip: Since it's hard to perfectly balance RCS, especially when the CoM moves as fuel is burned, you can press TAB for 'fine control.

Maybe somebody has changed their key bindings. Isn't it caps-lock by default?

Anyway, if neither of the two ships are big and unwieldy, you can use target SAS to line both ships up simultaneously. I think the ship you are not controlling will keep target SAS active as long as you are close to it.

Pic 1 - Ships have 0.0 m/s relative velocity. The docking ports I want to join are on the right-hand end of both ships.

Pic 2 - Target ship (bottom) is active. The desired port to dock has been set as "control from here" and is targeting the docking port on the other ship. When SAS is set to target the ship swings around to point at the docking port on the other ship.

Pic 3 - Docking ship (top) is active and again the desired docking port is set to "control from here" and is targeting the docking port on the other ship. However, this time when SAS is set to target, both ships swing around at the same time to line themselves up.

When things stop moving go back to the target ship, deselect the target and move control back to the usual place. I also usually turn off SAS. If things are wobbling I might briefly go to 5x warp.

Using Mechjeb to dock these two ships, it initially reported that they were misaligned by just 0.01m. (But ymmv.)

jPsDtZQ.png

KXXitb7.png

tOdY1xN.png

Edited by mystifeid
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Posted (edited)

This might sound like a "cliche" advice, but go slow, creep up to ship and don't rush it. When I'm within 200km I usually go into an orbit just a few km higher or lower so that the relative velocity and distance is as low as possible when I rendezvous with the target ship.Make sure the navball is in target mode and learn how to use the nodes. If you find yourself floating away from the target ship, burn towards the retrograde node, this will kill the relative velocity between you and the target. Then you rotate the ship towards the target node and burn towards that node slowly, when you're within 100m try not to exceed 5 m/s, patience is key. Switching to the target ship and having it align towards you is also good advice.

Also make sure that the ship has a decent reaction wheel, and place the RCS thrusters slightly above the center of mass in the editor to compensate for the fuel you use on the way. Also make sure ths hip is orientated with the hatch up so that it moves in the direction you expect it to, this will make it much easier to "translate" the ship into position.

 

Rendsvouz and docking is something that's almost unfathomable the first time you do it, but when you've pulled it off for the first time it's like something "clicks" in your brain and it all suddenly makes perfect sense, so don't be discouraged.

Edited by Mjarf

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I actually find docking fun, rather than a chore and generally don't have any issues with it. If I do have problem, then it's usually because I've been impatient and not reduced my approach speed sufficiently, or rushed things in some other way.

A few tips for a good docking.

1. Set up a good close renedezvous, at most 500m but prefereably quite a bit closer (mine are typically 100 - 200m). This is partly to avoid impatience when manouvering in to dock, that can raise it's ugly head if you're starting your approach from too far out.

2. Move in to about 20 - 50m (depending on the size of the craft involved) then reduce your velocity relative to the target to zero... it's best to know your way around the navball to do this.

3. Target the docking port on the other vehicle that you want to dock with and line you ship up with it.

4. Switch to the target craft and repeat step 3. for that vehicle, so it's lined up with your craft.

5. Step 4. will most likely have made the aim of your ship on the target a bit off when you rotated the target craft, so correct the aim of your ship at the docking port again.

6. Switch back and forth between your the two craft a couple of times to realign them, until the ports are looking straight at each other.

7. Hit the RCS to move your ship in towards the the target at a 0.5 - 2m/s until just a few metres from it, then reduce speed to under 0.5m/s, so you have time to correct last minute errors in alignment.

8. Dock.

 

A couple of other ideas.

If you are docking a small craft and you find that when the docking ports touch that the alignment is off, even quite a bit (say 10 - 20 degrees), then turn off SAS and you'll find that the docking port magnets pull the ships together more easily.

Get a docking camera mod, e.g. this one...

I've used them on and off and they provide a useful tool, while also giving the whole exercise a more cinematic feel.

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Posted (edited)
11 hours ago, strigon said:

A big tip is to make sure each vessel is pointed along the same axis - most people like Normal/Antinormal since they don't drift - before docking. Just use SAS to hold that position on both craft, and the biggest problem - orientation - is solved.

I never thought of it that way. This certainly makes it easier to orient the craft. Been playing for 800 hours and still learning new stuff. I mastered docking a long time ago, I do it without RCS, but now I've learned how to do it on the "cheap" and without the vessels drifting. I usually take a long time to dock and strongly rely on both ships being controllable or else it is a bit inconvenient.

Edited by mystik

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Posted (edited)

some great advice above...I agree that you don't have to go to an automated docking mod. Once I learned how to do it manually it's my fav part of piloting and it's been fun to learn to finesse approaches for various reasons - like docking on the far side of a large station and having to plot a course past the station that let's you flip around and dock with the least effort...this can be really rewarding.

Here are the key things that make docking fun for me:

  1. Use RCS Build Aid - this isn't automating docking, it's just giving you access to information that lets you place RCS more precisely. When I'm positioning a ship's RCS I adjust the fuel levels of the craft to where the level will be when I'm actually docking. For example, if I'm building a lander I know that the docking maneuver will occur on the return trip to orbit when most of the fuel was expended taking off from the moon/planet. So I lower the fuel levels to nearly empty.
  2. Follow any of the many guides for rendezvous and docking to get yourself within .5 - 2 km of your target. From there you want to make sure your navball is in target mode.
  3. Use one of the docking assistance mods - not an autodock mod, just one that gives you more info. take a look at Docking Camera that @purpleivan suggested or @NavyFish Docking Alignment Indicator (this is the one I use). If you think this cheating, consider that tools like this are standard on craft that need to perform docking in real life. They're not doing it for you, they're giving you the tools you need to visualize and execute a really complex series of 3D maneuvers.

Ultimately it's your game and the goal is to have fun, so find the way that maximizes your fun.  :) 

Edited by Tyko

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3 hours ago, mystifeid said:

Maybe somebody has changed their key bindings. Isn't it caps-lock by default?

Gah! That's the sort of neuroflatulence I get for posting when I should be asleep. Absolutely, I meant to say [CapsLock] for fine control. But hey, that key is right below what I said. Fixed...

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Thanks for all the tips.  I'll be giving this another shot this week.  I scuttled my existing space station (mainly due to lack of docking ports on the Rockomax multi-connector), so I'll be sending up new space station modules this week.

Is there an updated version of RCS Build Aid?  I believe I did load that mod, did see a button for it while in the VAB, but, never saw it "do" anything.  I am using 1.4.3, so wasn't sure if it worked correctly with that version.

I do use the Docking Port Alignment mod already, with some degree of success.  Still learning.  I'd hate to use Mech Jeb to do it for me.  Never used that mod, and would like to learn the proper non-assisted method....but would also like to know there is a last resort for me. :D

Hopefully I can respond to this later this week to report I successfully docked the 3-4 pieces of my station without spending 3-4 hours each attempt.

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I'm noticing a lot of people are suggesting having both ships line up with each other; That's good when you're docking two ships together.

When you're docking to a big space station however, orienting a docking port on the station to an approaching craft isn't wise... it can end catastrophically for the station (unless you've actually designed this ability into the station when you built it). The reason for that is, while the individual modules docked to the space station might be RCS balanced by design, once it is all put together as a station, it's likely not to have any measure of balance any more at all. Turning on SAS for example, could send the space station off on a dance of RUD... as many new KSP players are finding out in building their first stations (there are many threads in here about that lately). Similarly, attempting to rotate a big station about via RCS can put the thing into a wobble that could take hours to settle out... or require a jump into time-warp to cancel the movement... or even cause it to break apart if some sections are 'weaker' in connection than others.

 

I'm also noticing a lot of comments about COM shifting as fuel is used up. I thought that issue in general was addressed and solved in the v1.0.0 release, with balanced fuel use/drain. That being the case, the shift in COM should be negligible. Still, it would be wise while you're building your craft to check the COM position with fuel tanks full vs empty.

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Posted (edited)

I've never used RCS build aid, but some general placement tips:

1) Generally I use RCS blocks in groupings of 4 snapped N-E-S-W around the module's core. That way tapping I, J, K, and L always thrusts with 2 blocks in the direction you want to go.

2) On smaller vessels place your 4x grouping of RCS blocks around the anticipated COM when docking. On larger vessels you may need 2 or 4 sets of 4 RCS blocks. In this case too you want to balance these around your COM, rather than the geometric center of the vessel. This should keep things from rocking and rotating when you mean to translate. 

Edited by Pthigrivi

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2 hours ago, djr5899 said:

Is there an updated version of RCS Build Aid?  I believe I did load that mod, did see a button for it while in the VAB, but, never saw it "do" anything.  I am using 1.4.3, so wasn't sure if it worked correctly with that version.

 

The current version of RCS build aid from @linuxgurugamer is working in 1.4.x.

For some reason I can't get the CKAN install to work though. I get the same issue of not seeing the button. The fix was to download the mod and install it manually. The two supporting mods as installed by CKAN worked fine. So I installed it all via CKAN, then replaced the version of RCS Build Aid CKAN installed with the one I downloaded.

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2 hours ago, LordFerret said:

I'm noticing a lot of people are suggesting having both ships line up with each other; That's good when you're docking two ships together.

When you're docking to a big space station however, orienting a docking port on the station to an approaching craft isn't wise... it can end catastrophically for the station (unless you've actually designed this ability into the station when you built it). The reason for that is, while the individual modules docked to the space station might be RCS balanced by design, once it is all put together as a station, it's likely not to have any measure of balance any more at all. Turning on SAS for example, could send the space station off on a dance of RUD... as many new KSP players are finding out in building their first stations (there are many threads in here about that lately). Similarly, attempting to rotate a big station about via RCS can put the thing into a wobble that could take hours to settle out... or require a jump into time-warp to cancel the movement... or even cause it to break apart if some sections are 'weaker' in connection than others.

 

I'm also noticing a lot of comments about COM shifting as fuel is used up. I thought that issue in general was addressed and solved in the v1.0.0 release, with balanced fuel use/drain. That being the case, the shift in COM should be negligible. Still, it would be wise while you're building your craft to check the COM position with fuel tanks full vs empty.

The COM will move if the craft has only one tank, for example a small crew transport. The RCS thrusters don't have to be exactly lined up with the COM, the reaction wheel(s) and SAS will compensate if it's a bit off, but it shouldn't be too much off, of course.

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Re: station alignment...

I design my station to maintain a given attitude in orbit, then place the docking ports in such a way as to simplify the alignment and docking procedures. I generally use a prograde orientation for the station, and use an axial docking port for more frequent missions. Long term, semi-permanent, or outright permanent additions are attached to radial ports along the normal and radial axes. It makes alignment a heck of a lot easier.

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The fastest and most efficient way (in my opinion) is to get both Spacecraft get them within ~50m and match Velocities. (Put Target Speed on the navball) Point the two docking ports at eachother (right click the docking port and set as target:targetpro: ON BOTH Spacecraft) and just boost to 1 m/s and warp. The Magnets should do the rest. :)

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19 hours ago, strigon said:

A big tip is to make sure each vessel is pointed along the same axis - most people like Normal/Antinormal since they don't drift - before docking. Just use SAS to hold that position on both craft, and the biggest problem - orientation - is solved.

16 hours ago, StrandedonEarth said:

 you can press CAPSLOCK for 'fine control.'

9 hours ago, Mjarf said:

This might sound like a "cliche" advice, but go slow, creep up to ship and don't rush it.

Quoted for truth.

 

 

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Posted (edited)

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Edited by Enceos
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Posted (edited)

I mostly don't even use RCS at all when docking, the main engines work just fine, provided you have the docking port on the nose of your ship pointed along the direction of travel, which I find is the most common situation anyway.

 

Rendezvous near-ish to your target, then kill relative velocity. Point nose towards target, thrust a tad bit, then warp a bit until you're quite close. Say, well within 500m distance to the target. Then, kill relative velocity again by thrusting retrograde in Target navball mode. Now, make sure you have "Control from Here" set on your docking port and target the desired docking port and lock SAS to Target. (Optionally also enable SAS on the target vessel as well.) Once your orientation has stabilized and you're pointing right at the docking port, thrust a smidgen, probably not more than 1-2 m/s relative velocity, then coast towards the docking port. If all goes well, the magnets will kick in and latch you on right away. If not, and you bounce off or veer in the wrong direction after coasting, then you might need to lock SAS retrograde and kill your relative velocity again, and repeat the above. If all else fails, just back off a hundred meters or so and try again, but this shouldn't be needed for most situations.

 

Naturally, this works best when docking a small, nimble ship with plenty of reaction wheels, thus enabling snap-changes of orientation. For larger, more cumbersome craft, you may well need RCS thrusters or even auxiliary maneuvering engines.

Edited by Supercheese

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