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bubba

Docking Help / DOCKING ? HELP !!!

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i tried the organic docking  training . did not get docked ..but it was very helpful

been looking at this tutorial [ and others] :

 

i like written procedural , easier for me to see, i will +view+ a motion tutorial but no good for quick reference]

science is up good , have a top notch probe head with all the targets. 

Docking target 150 KM  +/- equatorial circular orbit .

Docking Trainer launched to 100 KM +/- circular equatorial 0.0 inclination[ Mun Plane]  terrier engine , big fuel tank , lots monoprop ,

step one : no problem ..  i am F5 with closet approach .2 KM[ 200 M]  differential speed less than 80

F9 bring me in 2 km from target closing , Nav Ball target mode , burn retrograde to zero differential , [ ? circularizing the trainer orbit] ]

then i burn to target [ 10-15 closing] ... no joy ,  i end up dancing around the target + Turning and Burning+   made me very dizzy , my reaction wheel and RCS authority inadequate to keep up .. rcs ports are at CG , i think i will reconfigure on next launch and have some well forward and aft of CG .

burning to target [pink circle]   prograde  matches , then retrograde ,, kind of a halo orbit about the target. .. when i gave it up as a lost cause i had blown the high point of my orbit out to 230 KM.. but then i  ran a pretty big tank of fuel through the terrier sometimes at full throttle ..

go around go around/  F9

just now i am paused  678.2 m from target , 9.9 m/s differential speed , target selected in the navball , to target selected in SAS  , pink circle and prograde marker +nearly congruent+ 

clearly i am missing a critical step/behavior ..

perhaps someone can help . happy to look at links and take advice.

 

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Posted (edited)

If you could post some screenshots, that would help.  But it sounds like you're doing mostly ok.

Once you get close ( < 200m away with zero relative velocity), switch focus to your Target vehicle, make sure its "control from here" point is the docking port.  Target your other vehicle, then set SAS to "Target".  Once it's pointed at your target, switch you SAS back to stability. (Leaving it on target has caused weird behavior for me.

Switch back to your Trainer, and again confirm that your "control from here" point is your docking port, and set your SAS to "Target".  Since you have RCS, don't touch your main engine for this.  Puff forward a bit with the RCS, using "H".  Don't get going too fast, as you'll need the RCS to slow you back down. ("N")

You want to use your translate keys, (IJKL), to keep you aligned.  Don't worry about what is up and down with the camera, keep focused on the navball.  You want your target and prograde markers to stay lined up.  Use short puffs of RCS with IJKL to keep those aligned.  When your docking ports are close enough for the magnets to kick in, hold F to temporarily disable SAS.  This will keep your SAS from fighting the magnets.

Edited by Geonovast

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Posted (edited)

ok.. no so sure if the docking target has the docking trainer + targeted+ will do

control from here + NOT set+ yet

if i ever get them stable i will try to do a screen shot [ humm which key was screen shot ?]

docking target is a hitchhiker can , pretty big fuel tank terrier engine , mono prop , big antenna[relay and direct] electrics .

3 dock ports around the can , one on the nose ,

edit:

i resumed :  10 m/s closing . closest approach was 90 m , it whipped by ,retrograde showed  , prograde showed . that halo orbit thing again . which key for screen shot ? ,prograde retrogrd ..

 missed approach .. the target is receding , 648 m relative speed 5 m/s ,   nav ball shows reticule [ spelled ? the little wing thing] centered on to target [pink circle]  retrograde marker is one ball over/.adajacent ... next encounter is in 32 min 91 m/s 31 KM closest approach. ..

 i could set a node , burn for a closer encounter , and try again .. i think plenty fuel and mono ,,

go around go around

or F9

as i recall my F9 puts me about 2 km away 80 m/s differential , closest approach 200 m ,approaching from the lower orbit , procedure would be to insure navball target , burn retro target to 0.0 relative ..

which course of action suggested .

i think ill take another turn around the planet and set a node.

ok.. set a node   14.6 m/s radial out and prograde , intersect 2 ,  t-24 , separation 0.1 km [100 m ] relative speed 19.6 m/s ..

switched focus to the docking target [hitchhiker can] set docking trainer as target , control from here on the nose dock port .

switch to docking trainer ,, burned [ mono prop ] at maneuver, did not go well , did not hit the mark for dip

 

It IS IMPORTANT to REMEMBER : turn off the rcs when reorienting it will throw these fine maneuvers off big time if ya dunt .. 

last execution was for 0.1 m/s > maneuver target

current state :intersect 1 t-13  +  separation 0.0 km  relative speed 17.2  m/s ..

i think i will F5 [quick save] this condition.

 

Edited by bubba

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Posted (edited)

Maybe i know where your problem is.

3 hours ago, bubba said:

F9 bring me in 2 km from target closing , Nav Ball target mode , burn retrograde to zero differential , [ ? circularizing the trainer orbit] ]

Do u burn to zero target velocity when still 2 km out from your target? If so, dont do that

 

3 hours ago, bubba said:

step one : no problem ..  i am F5 with closet approach .2 KM[ 200 M]  differential speed less than 80

Thats a good starting Point but just kill your target speed when u that .2km away. Than u can get closer with rcs

Edited by PrvDancer85

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My rules for intercepts and docking -- all homegrown hayseed nonsense -- are as follows:

Fine-Tuning Intercepts:

  • When you're headed directly for a target, the prograde reticle will be inside the target reticle, and the retrograde reticle will be anti-target.
  • When you're headed directly away from a target, the prograde reticle will be in the anti-target reticle and the retrograde will be in the target.

So, to alter course directly towards a target means moving the retrograde reticle towards the anti-target reticle.

  • The prograde reticle gets "sucked towards" forward thrust.
  • The retrograde reticle gets "pushed away" from forward thrust.

So, to make your intercept closer while slowing down at the same time, aim a little off from retrograde, in a manner that pushes the retograde reticle towards the anti-target.  This is best done within a minute or two of intercept for highest accuracy.

Done right, it's possible to zero in on your target and reach orbit at the same time.  The navball will show you the way.  Being in the same place as your target at nearly the same speed means nearly the same orbit, after all.

Docking:

Once you're close enough to worry about hitting your target, the target reticles themselves will move around!

  • The prograde reticle "pushes" the target reticle away from it.
  • The retrograde reticle "pulls" the target reticle towards it.

So to dock you must do three things:

  1. Match the angle of your target (have to eyeball this, don't know a good way to do this on navball)
  2. Push the target reticle into the center of the navball with the prograde reticle
  3. Keep the prograde reticle near the target

What this means in "real-world" terms is 1) Point the same direction as their docking port, 2) Line up with the target, 3) Move directly towards the target

The target will want to "shimmy away" when you get real close, you just have to keep on it by moving the prograde reticle around to push the taret back into the center.

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Posted (edited)

2km out was my F9 save state ,[ matching on transfer from lower orbit]  i +might + start the burn then , maybe did ,thrusting with a terrier ,

new save state :

intersect 1 separation 0.0  km relative speed 17.2 m/s .. T-8 ..

fuel on board the trainer [ or is it a tug?] monoprop 1179/1470 ,LF634 of 720  , oxi 775 of 880  f

like the 41st Ord Co. .. i got ++++ Power to Spare++++

whats that keystroke for screen shot ?

corona ..perhaps this will make sense to me in future ..

i am Unable to manually control , i gotta use the control head ..if things are moving slow and stable i can manually control , for example  i adjust manually on initial ascent to orbit , things seem to move slow then , to me.

 

i need to go out of doors and do work ,,

BBIAB

Edited by bubba

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Posted (edited)

ty .. tried  according to steam [ i now find ] ingame screen shot is F12 .. stand by

 

neither one seems to work

f12 seemed to give aerodynamic forces overlay disabled ,, im so confused now ..

need to work out of doors 

 BBIAB

 

ty all

Edited by bubba

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Posted (edited)

When you have closed to 90 meters separation, you have to stop. Attempting to do the entire rendezvous all in one maneuver is extremely difficult -- expert level stuff.

So you do your burn to get to 90 meters, and when you get there you burn retrograde until your speed has gone down to zero again.

Then you aim your nose at the target, and you go forward again -- but much more slowly when you are within 100 meters. You want a closing speed of 1 m/s maximum, probably.

You get a lot closer, and then you stop again.

Going in big circles around your target is what happens when you don't stop.

Edited by bewing
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Posted (edited)

status : ready to resume : intersect 1  T-5 :42 sec / separation: 0.0 km  relative speed 17.2 m/s 

ummm   do i copy  correct :  burn retrro  on target for 17.2 m/s  when below 100m separation  // insure rcs off / reorient to target .. ease it on in ..

 

first thing i strike F5.. on resume ..   ,,  then ,, then  ..

stand by  for execution

resumed , on pause  t-4   range 5.6 km ,, target speed 24.5   

t-3    range 3.5 km  rate 21.6  m/s

t-2  range 2.1 km rate 19.1 m/s .. anti target and  retro grade congruent

T-1   range 1005.2 m rate 17.7 m/s  anti target and retro grade congruent

T - 28 sec    range 417.8 m rate 17.3 m /s   anti target  and retro grde congruent

intention is on resume to pulse  the RCS for zero rate

Edited by bubba

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Posted (edited)

If you are circling the target, you've just figured out what moths feel like. This is called homing. And it is frustrating. The first real world attempts at Rendezvous/docking  did exactly this.

You want to Zero your speed when you're a couple hundred meters away.

when you are getting close, make sure you are in Target mode on the Nav Ball

On the Nav Ball the pink markers indicate the target motion (targets track relative to yours.). The pink circle is towards (pro-grade) the target, the pink cross-hair is away (retrograde) from the target.

Also on the Nav Ball are the yellow Pro-grade and retro grade markers that indicate normal flight. In target mode they will indicate motion towards or away from the target.

To come to a complete stop with a rocket motor, orientate your ship on the pink cross-hair, and give a little thrust.. you are hoping to see the normal yellow pro-grade marker move towards the pink cross-hair.

The goal is to centre the yellow movement marker on the pink cross-hair, you will need to adjust the ship so that you drag the yellow marker onto the pink.,

also watch your speed the whole time.

At this point you will need to select a docking port as the target, and use the mono-prop thrusters to dock.

Let us know how it goes.

Cheers!!

 

 

 

 

Edited by GrouchyDevotee

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sure wish i could ascertain  the key stroke for screen shot .. as both vessels shown

current state   66.4 m separation    rate : 0.2 m/s  

 

\ break

 30.7 m separation rate 0.5 m/s  

however the target is not properly oriented for docking ,,

one wonders if i can just  slip along  side by side while i sort this out

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Posted (edited)

i ca not do this ,, sorry ,, unable //

i had about 500 keystrokes descriptive and stupid windows [ or stupid me ] lost it

current state  a near approach ,, 16.4 m  rv of 1.2 m/s ,, halo orbit action ,,

i need a smart core to  help me ,,

 

Edited by bubba

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52 minutes ago, bubba said:

sure wish i could ascertain  the key stroke for screen shot .. as both vessels shown

current state   66.4 m separation    rate : 0.2 m/s  

 

\ break

 30.7 m separation rate 0.5 m/s  

however the target is not properly oriented for docking ,,

one wonders if i can just  slip along  side by side while i sort this out

If the target orientation can't be changed and you're alongside with zero relative velocity, you can just point you ship where it will need to be and gently move forwards. Once you're ahead of the target docking port zero out your relative speed again and then point at the docking port. From there RCS forwards and centre the prograde marker to the target marker using the lateral translation keys I,J,K,L.

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i am so sad i am unable to dock ,, a critical element ...

 i have been evaluating this program to recommend ,,

 up check

while quite entertaining  and displaying basic orbital dynamics it fails to incorporate  Lagrangian theory

 

i am so sad i was unable to execute docking ,, then again consider i was born in the first half of the last century 

 i was a young man working on the road when man first put foot on the moon  , where were you ?

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There is a mod that allows the game to incorporate N-body gravity. It makes the game run a lot slower.

Once you are within 20 meters, you have to stop again. But you use RCS to do it this time. The N key thrusts backwards.

Docking is the most difficult of all things that there is to do in the game (or in orbital mechanics). Each part of it takes practice.

Getting both ships pointed correctly towards each other is difficult, and takes time.

And I was just getting ready to go to Kindergarten. :)

 

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i will keep trying ....  i think my brains a little calcified ...  ,, know you this ,, i can see clearly what has been described as the the interplanetary throughway .. .. all those low energy   + ducts+   orbital transfers   via  lagrange points .. ...

when i picked up this program i did another too,  tested it and displayed true enough halo orbit about the L points ..  ,, this one seemed to be more fun and i recommend  for all  space cadets

..if i can not dock , i can not  load up a big package to send ,,  sure do need a +smart+  core to  help me dock

what i am really excited about  is real world nano sats .. little science package ,, a smart core ,, solar wings . ,,,  5 newtons thrust .. ..solar   wings are a complex thought ,   ,,,

 i could  elaborate

vbr mrb

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If you want to dock to another probe or ship, when you are about 30m away switch to the other ship (that should be "]" key). This way you can point it towards your ship and then go back to your ship ("]" again or "["). This makes things much easier.

I also suggest you use the "Smart A.S.S." module of the MechJeb mod, in Target mode, to help pointing your ship towards the target. It's a very useful tool, but does not automate everything, you must still plan your approach and manoeuver your ship manually.

Keep your speed low, when within 30m you should never be more than 0.5 m/s.

Docking is one of the most difficult things in this game, so please do not get discouraged.

I was a very little boy, I have confuse rememberings of watching the landing on TV at night with my parents.

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16 hours ago, bubba said:

what i am really excited about  is real world nano sats .. little science package ,, a smart core ,, solar wings . ,,,  5 newtons thrust .. ..solar   wings are a complex thought

5 newtons is a lot for a microsatellite!  Aim lower :D

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Posted (edited)

If you are open to mods, NavBall Docking Alignment Indicator is the first mod I ever got for this game, I find it makes it much easier.

And with that, this is my handy-dandy simple docking guide:

kQKWpun.png

And BTW, F12 works for screenshots under Steam, even as it bring up that overlay. So check your Steam screenshots folder. F1 is the KSP screenshot key, which works in and out of Steam, and dumps it to the screenshot folder in your KSP folder

Edited by StrandedonEarth

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If you are not averse to using mods I can highly recommend Navyfish’s Docking Alignment Indicator. I even did a tutorial on how to use it and there are several others on YouTube  

 

 

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