Advanced Question Target Offset

Cras

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I want to aim for a spot x meters behind or below an object in space.

How would you guys recommend doing such a thing?

Currently I use a procedure that involves IMFD and Precession MFD, but I fear it is not at all practical when aiming for large offsets.

So I am curious at how others would try and do this. See if there are other ways, mfds that can do it. The more options the better I say.

And as a disclaimer, I am seeking this information so to fly Shuttle Fleet on a rendezvous that is as close to the book as possible. My current procedure and knowledge of Precession and IMFD do not seem to be enough as it requires an unhealthy amount of RCS.
 

indy91

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You could try my Rendezvous Targeting script (shameless plug). It uses Lambert targeting with target offset. If you need help with it I'd be glad to answer any questions.
I think it is also implemented in SSU, but that probably won't work with the Shuttle Fleet.
 

Urwumpe

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I think it is also implemented in SSU, but that probably won't work with the Shuttle Fleet.

Not sure if it is already implemented, but the relative navigation (REL NAV) function is currently high on the priority list for SSU.

Shuttle Fleet has other tools available, there is a MFD made by David413 that implements the "Rendezvous and Proximity Operations Program"/RPOP notebook software that had been supporting the astronauts during the station docking missions.
 

indy91

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Shuttle Fleet has other tools available, there is a MFD made by David413 that implements the "Rendezvous and Proximity Operations Program"/RPOP notebook software that had been supporting the astronauts during the station docking missions.

I use that all the time, too, and it is really useful for the manual phase of the rendezvous and docking.
 

Cras

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RPOP is quite useful, use it pretty much every time I rendezvous with something.

I was hoping to see how possible it is to gather something that is 'generic', and by that I mean be able to use it with many different targets and maybe even with many different ships.
 

indy91

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My script is so generic, it even needs knowledge in lua. ;)
I really don't know any MFD or so that can aim for offsets, that is one reason why I made one myself. If there is one, I would be very interested to use it myself.
If you want I can modify the script so that it is not only usable with the Space Shuttle + ISS. What kind of input parameters did you imagine?
Sadly I don't know enough C++ yet to program a MFD :(
 

Cras

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I haven't had the chance yet to try it, only read the documentation thus far and it sounds like it will do what I am looking for.

Though reading it, it did sound like the ISS is hard coded as the target. Really that is about the only thing that I would ask be expanded upon, so rendezvous can be done in similar fashion with other objects, be it a different space station with a different name, or the Hubble Space Telescope, or maybe try and use the XR-2 to rendezvous with a space station in the same manner.

I hope to try it out either today or tomorrow and I will report back my experience with it.

:cheers:
 

Tommy

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IMFD is fine for this. Use an angle of 0 for leading, 270 for "under". If the dV is high adjust the TEj - and be on the final orbit before intercept (according to SyncMFD)
 

Cras

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I assume these number go in the target offset values in IMFD. Does it matter LON or LAT?

and then insert distance under RAD?
 

jarmonik

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I assume these number go in the target offset values in IMFD. Does it matter LON or LAT?
and then insert distance under RAD?

Use the LON and keep the LAT zero.

The Offset mode must be set to "Vel. Frame" (above the offset settings)

LON (0) = In a front
LON (90) = Above
LON (180) = Behind
LON (-90) = Below

Press "Cnt" to center the ISS and then zoom in with "Z+", You should see the ISS as a grey circle and the offset vector.
 
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