How do you rendezvous with another craft in orbit?

[Evenger14]

First off, I really suck at orbits. (I love MechJeb) Anyway, I have several crafts in orbit, and cannot for the life of me rendezvous with them. I've come close-ish (18KM) but never got close to one. Most of the time I have a problem with being in a different (however so slightly) plane than the target craft, so I cannot meet with them. I was just wondering if there is a certain technique to doing it? I've tried using the MechJeb rendezvous tool but it just gives me the targets velocity and altitude, which while they have gotten me closer to rendezvous than without it, it still isn't enough..

Idea:

It would be awesome to have some kind of in game thing, where you select the target you want to rendezvous with as you are setting on the launch pad, and it tells you when you need to launch, i.e. T-20:00 minutes to Launch, along with a suggested flight path on the map screen, and a suggested prograde point on the Navball. Or just have an autopilot to launch and get into orbit for you. Just an idea, I don't even know if that would be possible to have or not.

[timpossible]

There is a mech jeb tool that does the "T-20:00 minutes to Launch" thing. while in ascent auto pilot, down the bottom there is a "Time launch for rendezvous" click that and it should let you set a target and auto warp to T - 15 seconds and let you sit back and watch the launch. However i think you have to set your own apo and peri altitudes still and your orbit inclination. hope it helps

[Cykyrios]

It would be awesome to have some kind of in game thing, where you select the target you want to rendezvous with as you are setting on the launch pad, and it tells you when you need to launch, i.e. T-20:00 minutes to Launch, along with a suggested flight path on the map screen, and a suggested prograde point on the Navball. Or just have an autopilot to launch and get into orbit for you. Just an idea, I don't even know if that would be possible to have or not.

This might be possible in a future update, thanks to this.

In the mean time, I suggest you learn a bit more about orbits and how to affect them to do what you want. Knowing this will help you tremendously. I made a

, though I might have to make another, more in-depth one.

Good luck!

[nhnifong]

Selecting a ship in the mechjeb rendezvous tool enables more buttons in the smart A.S.S. tool.

The button RVEL- will point you in the direction such that if you burn you will slow down relative to your target.

The TGT+ button will point you at the target.

If you are close, like within 20km, and you alternate between burning in these two directions, eventually you will get there. (warp till your distance to the target hits a minimum, zero out your relative velocity, and burn TGT+ until your ETA to the target is about 100s, rinse and repeat.) It's kind of like the iterative proportional fitting algorithm.

Edited October 6, 2012 by nhnifong

[Evenger14]

There is a mech jeb tool that does the "T-20:00 minutes to Launch" thing. while in ascent auto pilot, down the bottom there is a "Time launch for rendezvous" click that and it should let you set a target and auto warp to T - 15 seconds and let you sit back and watch the launch. However i think you have to set your own apo and peri altitudes still and your orbit inclination. hope it helps

Tried it, but I must be doing something wrong because it put me on a higher plane that my target. Maybe when they implement docking they will do something about rendezvous.

This might be possible in a future update, thanks to this.

In the mean time, I suggest you learn a bit more about orbits and how to affect them to do what you want. Knowing this will help you tremendously. I made a

, though I might have to make another, more in-depth one.

Good luck!

Thanks I'll check out the video!

[Nibb31]

First of all, make sur that your target craft is on a nice stable circular orbit. This makes this much easier the first time. Use the Orbital Operations AP, PE and CIRC buttons to achieve that.

There are 3 things to rendez-vous:

- Altitude: Well, you need to have pretty much mastered circular orbits and changing altitude.

- Inclination: Look at the map, wait until you get to the intersection of both orbits and burn normal or antinormal (NORM+ or NORM- on MechJeb).

- Period: The other ship is either before you or after you on the orbit. To catch up, lower your orbit. To slow down, raise your orbit. As you get closer, you need to reduce the altitude difference.

With a bit of practice, this will get you within 5km. At that distance, forget about orbits, and use RCS for the final approach.

I don't use the rendezvous tools in the MechJeb, because they are confusing. Especially do not use the TGT+ button, because that just points you at the target and you lose any perception of how you are moving relative to the target (whether you are above it or below it). I find it easier to maintain a PROGRADE attitude and thrust X, Y and Z to approach it.

Edited October 6, 2012 by Nibb31

[Evenger14]

[ATTACH=CONFIG]34376[/ATTACH]

This was as close as I was able to get, but only because I ran out of RCS fuel and could not maneuver close. However I got close enough for a crew transfer. Took me 5 orbits, each coming closer and closer to the target craft, needing to adjust my orbit to slow down or catch up with it. Still I think there needs to be a better system for rendezvous if they implement docking, and I'm sure they will do something to help out noobs like me.

[Vanamonde]

That's actually really freaking good for your first time. How fast were you going when you passed?

[Evenger14]

Thanks, but I cannot really remember, I know I was able to get close to the same speed, though there must have been a slight difference since I eventually wound up further away from it. But those crafts were in a LKO, and had a near perfect equatorial orbit. I have a orbital platform in a much higher orbit, however it's orbital plane is a little wacky. Might relaunch it and try it later.

[cardgame]

This is probably not ideal, but the easiest way I can think of to force a rendezvous: Have your target in a stable circular orbit, launch on the same direction and inclination, establish a slightly elliptical orbit. Time it right, then burn towards your target and retroburn as you approach to kill speed and match AP/PE.

[dodrian]

I just rondevouz'd for my first time

I used the suggestions above, but when I was about a 1~2k from my target hit -RVel and killed my relative velocity. Then I put +TGT, gently swam towards the target, then -RVel when they looked like they were no longer headed towards eachother. Repeating this several times got me within about 50m of the vessel, where I hit +PAR, and gently guided it in the final meters.

I had originally wanted to grab the vessel, but my claw blew up when it touched the other one. So, I completed my crew transfer with EVA, and sent the resupply ship home :-)

<img src="http://kerbalspaceprogram.com/forum/attachment.php?attachmentid=34457&d=1349618118" />

[Evenger14]

This is probably not ideal, but the easiest way I can think of to force a rendezvous: Have your target in a stable circular orbit, launch on the same direction and inclination, establish a slightly elliptical orbit. Time it right, then burn towards your target and retroburn as you approach to kill speed and match AP/PE.

This is actually how I did it.

I just rondevouz'd for my first time

I used the suggestions above, but when I was about a 1~2k from my target hit -RVel and killed my relative velocity. Then I put +TGT, gently swam towards the target, then -RVel when they looked like they were no longer headed towards eachother. Repeating this several times got me within about 50m of the vessel, where I hit +PAR, and gently guided it in the final meters.

I had originally wanted to grab the vessel, but my claw blew up when it touched the other one. So, I completed my crew transfer with EVA, and sent the resupply ship home :-)

<img src="http://kerbalspaceprogram.com/forum/attachment.php?attachmentid=34457&d=1349618118" />

Is that a space station??

[dodrian]

Is that a space station??

Yeah, it is :-), mainly made from parts of the Deep Space Missions pack. It also functions as a command center for the Remote Tech pack, and has interplanetary dishes pointed at all corners of the solar system. I haven't yet sent missions to those corners, but it's good to have the infrastructure in place. I felt that Jeb, Bob, and Bill had done a good job though, so wanted to relieve them, return them to Kerbin and get them prepped for onward exciting missions!

[Evenger14]

That, good sir, is awesome!

[Evenger14]

My current space station:

[Corbald]

Is that a space station??

It's clearly a mun.

;D

[potatobabe]

Using ORDA & Erkle Mod it becomes moderately easily if you can get a craft to circularise within 1-2km of the other and use the relative velocity arrow with RCS

[jardeon]

I must be missing something, because when I use RCS to maneuver towards the other craft, I wind up throwing my orbit way out of whack.

[Qumefox]

It's clearly a mun.

That's no mun...

And when your accelerating towards a close object, the other side of your orbit IS going to change.. but it changes back once you decelerate to match speeds with your target.

[tuliomir]

This 13 minute video from PebbleGarden taught me everything I needed to know about rendezvous:

http://www.youtube.com/watch?v=7LBWNNYN80g

And, may I say, this is quite a HARD rendez-vous he does on the video!

If the format pleases you, go watch the 4 other videos he made before this one. They are REALLY helpful! And, of course, check his complete tutorial on Orbit Mechanics on the forum.