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Mechjeb rendezous


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I\'ve got a ship within 15km of the station I want to rendezous with, both orbits are, near as damnit, 400km. I\'m equipped with mechjeb, a small engine and plenty of RCS.

I don\'t understand how to use mechjeb to close that last 15km (or, failing that, how to close it, myself.)

Can anyone shed some light on this?

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I hate using mechjeb, because in kerban orbit,

I\'m going around 2.5k meters or second

and for it\'s sync burn

it burns my rocket up to escape velocity around 3k

and it says 'Your rednezvousing fail, Did you...' etc.

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Basically, for Mechjeb\'s Rendezvous Module, the informational parts work great:

, the ship-orienters work fairly well (but fight with the Smart ASS buttons, so I tend to only use the latter)

And the autopilot parts should be avoided.

This post taught me how to use the Rendezvous Module when it was still called RinComp:

http://forums.somethingawful.com/showthread.php?action=showpost&postid=404079876

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I\'ve got a ship within 15km of the station I want to rendezous with, both orbits are, near as damnit, 400km. I\'m equipped with mechjeb, a small engine and plenty of RCS.

I don\'t understand how to use mechjeb to close that last 15km (or, failing that, how to close it, myself.)

Can anyone shed some light on this?

You can use the randezvous table (Credits to Kosmo-not). The topic is somewhere in the How-to section (go for keyword randezvous). The table gives you the distance when to burn. After that its just some small rcs burns. Just look at the table and you will understand.

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I don\'t think the rendezvous table helps much with the last 15km.

I use Mechjeb\'s Rendezvous Module for information, and the 'Kill Rel Vel' and 'TGT+' functions of Rendezvous Module window.

In the Mechjeb panel click 'Rendezvous Module' > in the Rendezvous Module window that appeared click 'Debris' (or 'Vessels') > in the list click the debris or vessel name > click the 'Rendezvous ' button.

It shows useful information: distance to target, relative velocity, relative velocity for x, y and z axis separately, distance along x, y and z axis separately.

Y axis seems to be the length axis of your ship, so when pointed toward the target (use TGT+), any velocity in x and z means there is lateral movement relative to the target.

'Kill Relative Velocity' uses RCS and should only be used when relative velocity is low.

When relative velocity is large use the info to orientate your ship to use main engines to reduce relative velocity.

TGT+ points the vessel directly toward the target.

Oftentimes Mechjeb\'s +/-Rad, +/-Norm, and Prograde/Retrogade (in the Rendezvous Smart ASS window) are close enough to the direction where you want to burn, as long as distance to target is more than a few km. Watch the info in the Rendezvous Module window to see if you\'re going in the right direction.

When close (<20km) to the target i first enable TGT+ (disable any Smart ASS function), then use Kill Rel Vel while TGT+ is enabled.

When relative velocity in x y z is near zero, disable Kill Rel Vel and burn toward the target for a modest amount of delta-v, reduce delta-v as the target gets closer. Use Kill Rel Vel as the situation requires. Watch rel vel xyz.

In the image below the Rendezvous Module window is in the top left.

I have TGT+ enabled. Note that 'Distance' is the same as Rel Pos y (middle number of the three numbers above the 'Disable TGT+' button.

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From that picture, I can say you will need to be a lot closer before using the rendezvous features. You need to be within 1-2km before trying to kill relative velocity.

Use Kosmo-Not\'s table to get that close, then use the mechjeb features to finish the job.

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From that picture, I can say you will need to be a lot closer before using the rendezvous features. You need to be within 1-2km before trying to kill relative velocity.

That\'s correct. In the image i am not trying to rendezvouz, just showing the rendezvouz window.

Use Kosmo-Not\'s table to get that close,

It\'s quite possible to get close without using that table.

then use the mechjeb features to finish the job.

The OP\'s question is *how* to use MJ for rendezvouz, i tried to anwser that.

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I dont see the need for tables at all. Put the craft in orbits at the same altitude, then if you are behind in orbit, drop your orbit slightly to catch up. If you are ahead, increase orbit to slow down. Once you can see tyhe craft (within 100km), burn towards it or however you need to to just keep the distance going down. Then just slow yourself down until the relative velocity as you see the numbers change is low or zero. Done.

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Of course you don\'t need the tables, they just help accomplish it in a very simple way that is also quick. And after trying a rendezvous with mechjeb, my advice would be to use the tgt + command, and use RCS to steer until you are close. Then turn off tgt + and make the relative velocity 0.

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Finally! With everyone\'s help and a whole lotta saving/loading, I finally managed to rendevous with my StarHab space station. Once you\'re close enough to actually see the effects the TGT+ and kill Relative velocity buttons are actually fairly intuitive.

screenshot32.png

At 400km above the surface of the world, six kerbals are united

That\'ll keep my station equipped for another month!

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Good on you.

That\'s a pro looking station and nice formation flying.

Cheers, I just wanted a fairly simple station to practice rendezvousing with in anticipation of EVA, so it\'s got a hab module, some ASAS to stand in as labs and a utility modle.

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