How do I do an orbital rendezvous?

[Millitron]

I\'ve been trying to rendezvous with a satellite I deployed for the past couple hours now, and I\'m not making any progress. I know the game isn\'t persistent, but the satellite was deployed on the same launch, so that shouldn\'t be an issue.

What I tried was this. I launched, and banked to the east. I reached a fairly circular orbit with an apogee of 217km and a perigee of 208km. Once in orbit, I turned 90 degrees north, and fired off my satellite.* Note, the satellite was rear-mounted, meaning it went south. I then noted where I was in my orbit on the orbital map, and timewarped to a few minutes before I reached that point again. I carefully watched the skies, but saw no sign of my satellite.

Is it just not possible with our limited instrumentation?

*Thought I should clarify. I did this because I wanted to ensure as well as I could that the velocity provided to my satellite by the decoupler did not affect the altitude of the satellite\'s orbit. It should\'ve basically been in almost the same orbit as me, except at a slightly different inclination, correct? Further, it should\'ve intersected (or come damn close) my orbit at the point of release, correct?*

[Tiberion]

Unless you were using one of the low-power decouplers, you\'d have to be aligned perfect not to affect the satellite\'s orbit. If you aimed slightly up or down, or at any angle aside from a perfect 90 degrees, the velocity will change

Might just be hard to see - a common suggestion is to use the flare mods to make your satellite easier to see over a distance.

[Rascal Nag]

I believe that there are two points at which your crafts should come by, one where you deployed it and one opposite the point of deployment (like this picture), so you may want to try your luck there. I\'ve tried this before and had no luck-I was ready with my RCS thrusters to follow it when it came by, too.

[Millitron]

After more careful trying today, I think it\'s impossible. In the picture I have attached, notice how far above me the advanced SAS satellite I deployed is. I deployed it as close to parallel to the horizon as I could, as close to perpendicular to my velocity as I could, with the gentle decoupler, and in a very circular orbit, but as you can see after only a couple of minutes its already in quite a different orbit. I think the issue is with timewarping. I timewarped to 4x right after deployment, and watched the satellite move in a straight line, not along an orbit. I think whats happening, is that once a separated thing goes on-rails, it never comes off-rails.

[trydyingtolive]

Hi there. Using the current version it is next to impossible. Believe me I have tried. The new experimental build adds the RCS units into the mix. When used correctly it makes it pretty each to catch up to and bump into anything you can see. Here is a video showing the 'Docking'

and here is the how to make it video

[Millitron]

Hi there. Using the current version it is next to impossible. Believe me I have tried. The new experimental build adds the RCS units into the mix. When used correctly it makes it pretty each to catch up to and bump into anything you can see. Here is a video showing the 'Docking'

and here is the how to make it video

This isn\'t exactly what I\'m talking about, though it IS pretty cool. I want to deploy a satellite into a different orbit than mine, and then at one of the orbital intersections I want to find it again.

[Saaur]

Hi there. Using the current version it is next to impossible. Believe me I have tried. The new experimental build adds the RCS units into the mix. When used correctly it makes it pretty each to catch up to and bump into anything you can see. Here is a video showing the 'Docking'

and here is the how to make it video

Typo at 3:20. Should be \'motors\' instead of \'mortors\'.

Not sure if you care, but I figured I\'d point it out.

[Rascal Nag]

I did it!

The trick was to make the other part head a bit downwards. Otherwise it gets way too high. I didn\'t get the release picture, but here are two points where we met up.

Edit: it seems though that the two orbits get farther and farther from each other every time they meet up. I added another picture, now the piece is below me and pretty far away...

[Millitron]

Zeus0moose, THATS AWESOME.

Quick question though, did you use time compression? Cause I think that was what was screwing me up. I don\'t think separated parts react well to going on rails or coming back off rails.

[Rascal Nag]

Zeus0moose, THATS AWESOME.

Quick question though, did you use time compression? Cause I think that was what was screwing me up. I don\'t think separated parts react well to going on rails or coming back off rails.

Yes, I did. That\'s probably why the paths got so different each time, because warping seems to screw with the velocities a bit. If I waited out the entire orbit without compression, I could probably get them to be a lot closer, but maybe not. Might just be simple precision and I\'m just not quite accurate enough to keep the orbits close.

Edit: Also, I think I\'m going to try again, but shoot it off vertically. Pinpointing where exactly the horizontal midpoint between pro and retrograde for perpendicular deployment is difficult with no marker, but since I\'ll have the dot on the navball with vertical deployment it should be easier. They should, like horizontal deployment, meet up at two points, so it may be just as, if not more effective.

[Millitron]

There\'s one big problem with vertical deployment. While both orbits DO intersect, there is no guarantee that both you and your target will be at the intersection at the same time, because your target\'s orbit could have a quite different eccentricity, and thus a quite different orbital period. Without better instruments, or at least better information about how much velocity decouplers add, a vertical deployment seems to be leaving quite a lot up to chance.

[Rascal Nag]

There\'s one big problem with vertical deployment. While both orbits DO intersect, there is no guarantee that both you and your target will be at the intersection at the same time, because your target\'s orbit could have a quite different eccentricity, and thus a quite different orbital period. Without better instruments, or at least better information about how much velocity decouplers add, a vertical deployment seems to be leaving quite a lot up to chance.

I tried it, got the same results as horizontal. Came close at first, then drifted further on every orbit.

[icefire]

The orbital periods of the two parts are different because no matter how much you try with this instrumentation you can never get the part to jettison exactly on the horizon/normal +/-. Which means the epoch will fall out of sync over time.

On a note, I don\'t really think this can be called rendezvous. Real orbital rendezvous usually means having one passive orbiting object and another active one trying to get to it. This has them both being passive and just meeting up at the intersecting node.

[Monger]

Even if we already had a persistent world in KSP: a rendezvous with an already deployed satellite without instrumentation is like shooting a fly from several kilometers distance.

As we can see from this thread: it is even hard enough to hit a specific on your own trajectory again.

[Ivan Ivanovich]

If we already had a persistent world, just use the problem our real space program is running into to your advantage: Launch enough junk to litter the equatorial orbit enough that you almost HAVE to hit something when you get there.

[Panichio]

After more careful trying today, I think it\'s impossible. In the picture I have attached, notice how far above me the advanced SAS satellite I deployed is. I deployed it as close to parallel to the horizon as I could, as close to perpendicular to my velocity as I could, with the gentle decoupler, and in a very circular orbit, but as you can see after only a couple of minutes its already in quite a different orbit. I think the issue is with timewarping. I timewarped to 4x right after deployment, and watched the satellite move in a straight line, not along an orbit. I think whats happening, is that once a separated thing goes on-rails, it never comes off-rails.

Yeah, time warping just stuffs up everything in KSP.