strider3

MechJeb2 tutorials?

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I am trying to find tutorial, preferably video, of how to use MechJeb2 autopilot to control 1. a full launch/orbit/rendezvous with my space station. 2. a landing to a specific spot on a celestial body. What I've found, so far, on Youtube is either not very detailed or not very understandable (due to language difficulties)...or both. I am..."that guy"...I need a complete and detailed, step-by-step tutorial for how to set up and perform both of these auto pilot functions. I am not asking for someone to post that here...just a link to the info. No offense intended but if it's video, preferably someone who speaks English well.

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For launch to rendezvous - here's how I tend to do it, assuming a station in near-Kerbin orbit:  (Note that I do not use MechJeb to do the actual launch.  Gravity Turn does a better job...  By 'near-Kerbin I mean pretty much anything inside Mun's orbit.)

  1. Launch to orbit.  (With Gravity Turn it's just click 'launch' really...)  Note to be careful that you do *not* launch to the same altitude of the station.
  2. Once circularized, set the space station as the target.
  3. Open MechJeb Maneuver Planner, select 'Bi-Impulsive Transfer to Target'.
  4. Plot and execute burn.  (Note the burn may be up to 4 hours in the future.)
  5. In MechJeb Maneuver Planner select 'Fine-Tune Closest Approach to Target'.  Set distance to something large enough to miss the station, but close enough for what you need to do.
  6. Plot and execute burn.  (There may be little to no burn needed, and it may be immediate.)
  7. In MechJeb Maneuver Planner select 'Match Speed With Target', select 'At Closest Approach to Target'.
  8. Plot and execute burn.

You should now be floating next to your station.  Note this isn't the 'best' way to do it - MechJeb can in theory launch directly to rendezvous, which would be both faster and lower dV, but this is a general procedure that works in a lot of situations, and isn't extremely bad either.

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DStaal's method works. To directly launch to rendezvous (assuming the station is in a circular equatorial orbit).  You use launch to target.

  1. Once on the pad switch to map view and select the station as your target. You might want a launch clamp to provide power as waiting for the launch window could be awhile.
  2. Set your orbit altitude the same as the station.
  3. Make sure your phase angle is zero and auto warp is on to deal with the wait time.
  4. Launch.
  5. After the circularization burn is done, revert to launch.
  6. Now your phase angle will update to what it should be. Think of phase angle as how much you need to lead the target to hit it. Don't change any other settings.  If you tweak something that changes the ascent profile you need a new phase angle.
  7. Launch.
  8. Once the burn is complete you should be fairly close to the station. I've had it vary anywhere from a couple kilometers to a collision once.
  9. Use the rendezvous autopilot to get closer to the station. It automatically performs steps 3-8 in DStaal's instructions. There is also a rendezvous guidance mode that prompts you through the steps instead of doing them for you, so you can get a feel for the process.
  10. You can use the docking autopilot to finish docking, but I find it to more efficient to do it myself.

For docking I use the Docking Port Alignment Indicator  and set SMART A.S.S. to PAR- mode. This keeps my spacecraft aligned with the docking port so I don't have to worry about rotations, just translating.  You can also toggle over to the station and activate MechJeb for it to hold an orientation.  As long as the two craft are within a couple hundred meters MechJeb will operate on the ship you are not currently flying. It's kind of cool to get in range and see a station  spin around on it's own to align with the last mode I left MechJeb. 

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