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Need help with rendezvous


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So I've had KSP for awhile now and decided to make a refueling station so I can get to the mun. Problem is, when I get the two ships into the same orbit, I can't figure out how to get them next to each-other. If I burn prograde and speed up to meet the other ship, the orbit gets bigger, and a similar thing happens when I try to slow down. So I have no clue how to get them even near each-other :(.

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The way I do it is to have the second vehicle go to a lower orbit, then do a hohmann transfer from the lower orbit to the higher orbit so that both craft arrive at the intersection at the same time. It's easy to do once you get used to it.

Basically, you want the ship in the higher orbit to be a bit ahead of the ship in the lower orbit when you start your transfer burn. By setting the higher vehicle as your target and then playing around with maneuver nodes, you'll get a feel for the timing.

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Yeah, it's quite counterintuitive - if booth ships are on the same orbit, but your target is ahead of you, you burn retrograde (away from your target), with lowers your orbit and then wait, as this lower orbit will bring you closer to the other ship. Mabe you can find a few videos on youtube, is actually not so hard once get the hang of it.

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This is how I perform my rendezvous. First make sure your station is in a circular orbit, make the apoapsis and periapsis as close as possible to equal, it makes it much easier later.

With your new ship, get up into a stable orbit first.

Click on the station and set as target.

First thing is to adjust your inclination. Find the ascending or descending node and use the maneuver tool to set up a burn that will set your inclination to 0 degrees.

Next do a burn that puts your periapsis to the same altitude as the station. There are usually two of them. This shows you the location of your orbit that is closest to the target orbit and the position of the target ship as the same colored marker, but upside down. On the intercept node, add a maneuver. Adjust the green handles until the target position matches up with the target node.

Do the maneuver burn and then after one more entire orbit, you and the target will be very close(I've gotten within 100 meters on a first pass) It depends on how accurate you are with your manuever. More accuracy with them equals less fuel and time wasted closing the gap once you are ready to chase.

At this point, if the navball doesn't say "Target", know you can click where it says "Orbit: 2145m/s" and it will change to Target and show a relative velocity. Now your prograde and retrograde icons in the nav ball will be used. Keep an eye on your distance to the target. If the number is increasing, burn retrograde until your relative velocity is zero, then burn towards the target. You will probably get close then fly past it. So be ready with your rocket pointed at retrograde and burn until your velocity is zero again. You can repeat this until you are within a few hundred meters and use RCS thrusters to close the last bit of distance safer.

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Since smaller orbits are faster than larger ones, you want to be on a lower orbit if the target is in front of you, and a higher one if it's behind you. Make sure you don't go too low; I have managed to deorbit a space tug by mistake because I was watching the rendezvous markers, not my periapsis....

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So I've had KSP for awhile now and decided to make a refueling station so I can get to the mun. Problem is, when I get the two ships into the same orbit, I can't figure out how to get them next to each-other. If I burn prograde and speed up to meet the other ship, the orbit gets bigger, and a similar thing happens when I try to slow down. So I have no clue how to get them even near each-other :(.

it took me a while but i finally managed :)

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Hello, Hackole.

You might find some useful information in a few of my tutorial videos, specifically parts 4 and 5 of the Phoenix Project.

The Phoenix Project (HD) (V0.18.4) - A series of lessons in orbital rendezvous and docking, under a variety of conditions.

As a playlist

Part 1 - Rocket Construction

Part 2 - Launch to Orbit

Part 3 - Rendezvous (direct intercept from launch)

Part 4 - Orbital Rendezvous

Part 5 - Challenging Rendezvous (eccentric, inclined orbit)

Also my Gamma To Delta video might be of use:

Gamma to Delta (HD) (v0.18.4) - An orbital transfer flight from stations Gamma to Delta, orbiting at 100 and 200km respectively.

Gamma To Delta

And Orbital Mechanics 101 might still contain some information you haven't already figured out.

Orbital Mechanics 101 (HD) (v0.18.4)

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