Realistic ISS Sync With The Shuttle

[Flying_Pie]

Hey fellas, I've been flying Orbiter for a couple of years now and I'm starting to get into it seriously. I've spent the last couple of days going through STS checklists and such but I'm lost on one big thing: when I'm doing my NC burns what am I aiming for in order to rendezvous with the ISS? I'd like to follow the missions down to the minute, but it's sort of difficult if I don't know what I'm aiming for with my burns. Anyone have any ideas?

Thanks

 

[Poscik]

NC occurs about 75km behind station, and It placing shuttle about 14km behind station. How to do that?

To make NH burn (it will place shuttle at NC point), use TransX. Set it up to be 75km behind. When burning, open SyncOrbit, set target, mode to Intersect. During burn, watch whether data on SyncOrbit appear. If yes, immidiately cutoff OMS. Then after one orbit, at our Intersection, burn until your DTmin will start increasing and cutoff when it will be 2.00. Now, after one orbit, You will be 14km behind station (Ti). At Ti open RendezvousMFD and let it make burn. To stop at RBAR, use AttitudeMFD.

 

[Donamy]

You should do a detailed tutorial Poscik, with pics and diagrams.

 

[Poscik]

I'll make this, but it will take some time

 

[Donamy]

great !!

 

[Flying_Pie]

Great, I'll give it a go. Thanks

---------- Post added at 04:23 PM ---------- Previous post was at 01:44 PM ----------

Alright it worked to some extent but I ended up ahead of the station, and I think I used more fuel than I had to.

Is there any way you guys know of to follow the burn schedule in the STS checklists? I've managed to find the schedules in there but I don't know where to find the planned orbit parameters after each burn, so I don't know what I'm doing when it comes time to do the burns.

 

[Poscik]

I told you, that you can. Following that path and doing NH, NC, NCC(if needed), Ti, MC1(if needed), MC2(if needed), MC3(if needed), MC4(if needed). Burn parameters are calculated by few MFDs.

 

[Flying_Pie]

I understand the approach, but what about beforehand? I'm lost on the OMS2, and the other burns (I see NC1 through NC4). I can try to wing it but I'd prefer to be on schedule and precise.

Thanks for your help, I appreciate it.

 

[Poscik]

Too keep mission real, you need exactly the same state vectors like real mission have. The same launch date, the same target LAN and INC, generally - all the same as real. Non-spherical gravity sources and gravity gradient torque have to be enabled, but I didn't try flight to ISS with non-spherical gravity sources etc.

For OMS and NC burns, you have to find orbit apogee and perigee before and after those burns. But seriously - I think we are not able to do super copy of real shuttle travel (yet).

 

[flying coffin]

But seriously - I think we are not able to do super copy of real shuttle travel (yet).

Actually, we are. During the mission go to
http://spaceflight.nasa.gov/realdat...tions/Post/JavaSSOP/orbit/SHUTTLE/SVPOST.html

This lists burn magnitudes times, directions, and orbital elements, all which can be plugged into orbiter, by making the burns in orbiter, or using
scenario editorTLE.

I did this for STS127 (and others) and use David413's RT scenarios as a double check, and also elements from celestrak.com can be used as a double check. Of course, rendesvousMFD is used for the TI burn and the
MCC burns, but I arrived on the RBAR just about when STS127 did.

 

[Poscik]

Thanks for that reply. I missed it somewhere. But they don't have data for archival missions. Also question here. How to apply M50 DV?

 

[flying coffin]

Thanks for that reply. I missed it somewhere. But they don't have data for archival missions. Also question here. How to apply M50 DV?

I try to save this data for every mission. I don't use the M50 DV, I use the LVLH. It's much easier. Most burns (OMS2, NC1-4, NH) are prograde. If not prograde, it's usually
a plane change. (NPC)

 

[Flying_Pie]

Thanks for the link, although I'm a bit lost on it (I have a lot of reading to do apparently). Do you have any tips on how to complete a mission with a burn schedule similar to the real world? It would be nice to follow a mission to the second but if that's not possible I'd just like to know how to pull off a flight that makes me feel like I've done something

 

[flying coffin]

OK I'll take you through the first burn in the file as it existed shortly after launch.

   SHUTTLE  TRAJECTORY DATA
 
   Lift off time (UTC)  :  2009/196/22:03:10.000
   Area (sq ft)  :  1208.48
   Drag Coefficient (Cd)  :   2.00
   Monthly MSFC 50% solar flux (F10.7-jansky)  :   72.1
   Monthly MSFC 50% earth geomagnetic index (Kp)  :   2.19
   ET - UTC  (sec) :   66.18
   UT1 - UTC (sec) :    0.0
 
 
   Maneuvers contained within the current ephemeris are as follows:
 
 
   IMPULSIVE TIG (GMT)   M50 DVx(FPS)      LVLH DVx(FPS)      DVmag(FPS) 
   IMPULSIVE TIG (MET)   M50 DVy(FPS)      LVLH DVy(FPS)      Invar Sph HA
   DT                    M50 DVz(FPS)      LVLH DVz(FPS)      Invar Sph HP 
   ------------------------------------------------------------------------
   196/22:14:23.364           0.0               0.0              0.0    
   000/00:11:13.364           0.0               0.0              124.0  
   000/00:00:00.000           0.0               0.0              31.5   
   
   196/22:41:28.597          27.9              98.6              98.7   OMS2
   000/00:38:18.597          54.6              -0.1              123.9  
   000/00:01:06.793         -77.3               5.6              85.2

The launch occured at 22:02 GMT on the 196th day of the year 2009.
The line labeled OMS2 on the right (the OMS2 is my note) says that this burn occured at 22:41:28.597 on the 196th day of the year. This was also
38 minutes 18.697 seconds into the mission. The burn lasted 1 minute, 6.793 seconds. The burn resulted in a LVLH prograde DV of 98.6 fps
with a -0.1 fps off plane component (negligable) and a 5.6 fps upward
component. (I usually just do a prograde burn for this) It resulted in an orbit with a 123.9 NM apogee, and a 85.2 NM perigee.

There is some conversion to be done NM to KM etc, but it's not too bad.

 

[Flying_Pie]

That's exactly what I wanted man, thank you. Is there any chance you could upload your archives to a place where we could access them?

EDIT: Nevermind, first result in a google search:

http://www.aus-city.com/cgi-bin/dada/mail.cgi?flavor=archive;list=STSTLE_LIST

Thanks for all your guys' help, now I'm gonna see if I can pull this off.

 

[destinos]

I told you, that you can. Following that path and doing NH, NC, NCC(if needed), Ti, MC1(if needed), MC2(if needed), MC3(if needed), MC4(if needed). Burn parameters are calculated by few MFDs.

I find one of the biggest barriers to n00bs enjoying this sim is the esoteric terminology and abbreviations, etc. I, for instance, understand most of the MFDs pretty well at this point but the above graph is just over my head. Anyone interested in writing up a brief tutorial on how to interpret it, or if not, does anyone have a good resource for such a thing?

 

[flying coffin]

I'll try. The graph is a representation of distance from the target.
This is called rotating reference. It means local Horizontal and local vertical,
which rotates as we go around the earth.

The X axis represents horizontal distance to the target, and the Y axis represents vertical distance. The graph shown represents 2 orbits.

Notice that the spacecraft approaches the target from below.

 

[railfanatic844]

does rendezvous MFD work in orbiter 2010 P1? i currently dont have a windows and wont till next week so i thought i would ask. thanks! :thumbup:

-AJ

 

[C3PO]

does rendezvous MFD work in orbiter 2010 P1? i currently dont have a windows and wont till next week so i thought i would ask. thanks! :thumbup:

-AJ

I use it every day

 

[railfanatic844]

ah, that is very promising, alright.