OHM DSCOVR

[OrbitHangar]

Author: brianj

The NOAA "Deep Space Climate Observatory" (DSCOVR) will be positioned in a Lissajous orbit around the Earth-Sun L1 point while monitoring solar wind,CME's and imaging Earth. Launched on SpaceX Falcon9R from Cape Canaveral, 11 Feb 2015.

Add-on inc. DSCOVR spacecraft, launch and post-launch scenarios.
DscovrMFD to record spacecraft trajectory in rotating frame (Earth-Sun fixed), and show position/velocity data of L1 point relative to spacecraft, etc. Some flight notes and installation instructions in Doc/DSCOVR/ folder. Scenarios in DSCOVR folder.

 

REQUIREMENTS

Launch scenario requires "Falcon9R" add-on:

http://www.orbithangar.com/searchid.php?ID=6593



DOWNLOAD

 

[Cosmic Penguin]

Woohoo! I was waiting for this legendary spacecraft to be released for some Lagrange Point flying practices.

Are you going to update the F9 add-on to include grid fins as well?

 

[BrianJ]

Hi there,
yes, couldn't resist a bit more fun with L1, and the chance to make something to stack on the F9R.

Are you going to update the F9 add-on to include grid fins as well?

Would love to but all the code is in my dead PC :-(
Eventually, I hope to find a kind soul who might be able to retrieve the data from the harddrive(if it's still there).

Anyway, just a quick note that I couldn't find a launch solution for a flyback of the F9R 1st stage to the reported position of the barge, so in the launch scenario I moved the barge a little closer to shore. But maybe someone can figure it out. The F9R 1st stage is going a lot faster at MECO than on previous flights - my autopilot just can't quite handle it with the barge so far out.

Also, getting into a Lissajous orbit around L1 is very "seat of the pants" stuff, but can be done quite easily if approached logically. I put some notes and screenies in the docs. You need to know your way around IMFD Map though.

Cheers,
Brian

 

[IronRain]

I somehow knew you would release this
Thanks Brian!

 

[boogabooga]

Thank you :thumbup:

 

[sputnik]

Very nice!

I'm tempted to rendezvous with a DeltaGlider and accomplish a fast resupply of some vowels. Poor thing needs an "I" and an "E".

 

[Malky]

(arrgh, I'm just supid!)

Anyway, this is great addon and I'm glad you made it, Brian!

 

[Marg]

I hope BrianJ will check some compatibility with new Orbiter BETA 2015... Falcon Heavy works pretty well in that environment, and with DX9 client by Jarmonik (water shaders, etc.) views are spectacular. But Falcon9 goes in a bit weird launch profile... From Vandenberg AFB - the same (even Heavy Falcon). I know new Orbiter is still BETA, but anyway graphics+terrain updates are enormously big step ahead...

 

[BrianJ]

Hi Marg,
thanks for the feedback. I usually only work with the "current" orbiter build in order to keep things simple, but Martin has done such amazing work for the latest BETA version, and Jarmonik's DX9 client is looking very cool too, I feel I really should make time to get them up and running.

Thanks to an amazingly kind offer of help from one of the folks here on OF, it may yet be possible to salvage the lost VC++ code for the Falcons and continue development

Hope the launch goes off tonight OK. Good luck SpaceX, NOAA and everyone else.

---------- Post added at 06:29 PM ---------- Previous post was at 03:15 PM ----------

Just seen a bit more info about tonight's 1st stage flyback on Spaceflight Now
http://spaceflightnow.com/2015/02/07/new-challenges-await-spacexs-next-rocket-landing-attempt/

1st Stage Apa 130km
No Boostback burn, only reentry and landing
Aerobraking from Mach5 to 250m/s
Twice the dynamic pressure of last flight*

*I was wondering why I couldn't do this in Orbiter without pulling 10G(with the barge at reported position of Long -74.55 Lat +31.1). Maybe that's about right. Can be done manually with 22000kg fuel left in the 1st stage at stage-seperation, but my autopilot can't handle that kind of profile.

 

[Interceptor]

BrianJ you just amaze me,awesome job once again,and thats great news about the falcons.:jawdrops:

 

[boogabooga]

Is there any difference between Genesis MFD and DSCOVR MFD?

 

[BrianJ]

Is there any difference between Genesis MFD and DSCOVR MFD?

Not in the functionality. I renamed all the variables in the DscovrMFD C++ code to try and get to the bottom of the conflict with PitchRecorderMFD, but I'm still scratching my head. Weird bug. It seems to depend on which order you enable the MFD's on the OrbiterLaunchpad.

I'm currently messing around with a kind of "Launch to Earth-Sun-L1 MFD" which simply calculates the line of apsides (Perigee-Apogee) vector you need to go to Earth-Sun L1 (from LEO), and gives the launch azimuth and required inclination to get there in LEO, and time/orbit-angle to vector. If I can get it working resonably well(and fix the previously mentioned bug), I'll incorporate the DscovrMFD display for a kind of all-in-one EarthSunL1LaunchMFD

Cheers,
Brian

 

[Nicholander]

BrianJ, are you going to update it to have it launch on February 11th, (The actual launch date), and not to planned February 8th launch date?

 

[BrianJ]

BrianJ, are you going to update it to have it launch on February 11th, (The actual launch date), and not to planned February 8th launch date?

Yes, I better had - thanks for the reminder

EDIT: now updated on OH.

 

[Cosmic Penguin]

Is this a good orbital injection towards L1? :shifty:

BEGIN_DESC
Orbiter saved state at T = 2831
END_DESC

BEGIN_ENVIRONMENT
  System Sol
  Date MJD 57064.9910973410
END_ENVIRONMENT

BEGIN_FOCUS
  Ship DSCOVR
END_FOCUS

BEGIN_CAMERA
  TARGET DSCOVR
  MODE Cockpit
  FOV 40.00
END_CAMERA

BEGIN_HUD
  TYPE Surface
END_HUD

BEGIN_MFD Left
  TYPE User
  MODE Interplanetary
END_MFD

BEGIN_MFD Right
  TYPE Orbit
  PROJ Ship
  FRAME Equator
  ALT
  REF Earth
END_MFD

BEGIN_SHIPS
SLC40:Falcon9R/slc40r
  STATUS Landed Earth
  POS -80.5771995 28.5619578
  HEADING 10.00
  AFCMODE 7
  PRPLEVEL 0:1.000000
  NAVFREQ 0 0
  PST 0.1079 0.1841 2
  TOWER 1 1.0000
END
DSCOVR:dscovr\dscovr
  STATUS Orbiting Earth
  RPOS -5606815.98 -777455.39 -3992469.11
  RVEL 4148.509 -2687.183 -9492.500
  AROT 15.81 22.81 2.90
  AFCMODE 7
  PRPLEVEL 0:1.000000
  NAVFREQ 0 0
  SPR 2 1.0000 0 0.0000 0 0.0000
END
Falcon9R:dscovr\f9_dscovr
  STATUS Orbiting Earth
  RPOS -5606776.92 -777489.37 -3992591.59
  RVEL 4148.795 -2687.436 -9493.414
  AROT 15.80 22.63 2.88
  RCSMODE 2
  AFCMODE 7
  PRPLEVEL 1:0.002552 2:0.847700
  NAVFREQ 0 0
  FAIRS 1
  SOST 1 0 0 0 1 1
  SOPR 0.6667 200000.0 200000.0 35000.0 140000.0 Barge
END
Barge:Falcon9R\barge
  STATUS Landed Earth
  POS -77.4380000 30.0000000
  HEADING 90.00
  AFCMODE 7
  NAVFREQ 0 0
END
loco01:SaganSpaceport\\loco01
  STATUS Landed Earth
  POS 169.5370000 -0.8578510
  HEADING 270.00
  AFCMODE 7
  NAVFREQ 0 0
  CradleP 0.00
  CradleT 0
  Angle 0.00
  SpeedT 0
  SpeedC 0
END
Crane:SaganSpaceport\\XR5_Crane
  STATUS Landed Earth
  POS 169.5270000 -0.8542000
  HEADING 90.00
  AFCMODE 7
  NAVFREQ 0 0
  X_P 0.50
  Y_P 0.00
  Z_P 0.50
  X_T 0.50
  Y_T 0.00
  Z_T 0.50
END
LPad:SaganSpaceport\\ThemL_Pad
  STATUS Landed Earth
  POS 169.5375920 -0.8578510
  HEADING 270.00
  AFCMODE 7
  PRPLEVEL 0:1.000000
  NAVFREQ 0 0
  Arms_P 0.999946
  Arms_T 1.000000
  Lights 0
END
Radar:SaganSpaceport\\Radar
  STATUS Landed Earth
  POS 169.5330990 -0.8597000
  HEADING 270.00
  AFCMODE 7
  NAVFREQ 0 0
END
BPad:SaganSpaceport\\Big_Pad
  STATUS Landed Earth
  POS 169.5321950 -0.8686880
  HEADING 180.00
  AFCMODE 7
  PRPLEVEL 0:1.000000
  NAVFREQ 0 0
  Lights 0
  Config -1
END
Falcon9_Stg1:Falcon9R/f9_stg1
  STATUS Landed Earth
  POS -77.4380061 29.9999867
  HEADING 359.70
  AFCMODE 7
  PRPLEVEL 0:0.005086 1:0.322669
  NAVFREQ 0 0
  LEGS 2 1.0000 1.0000 1.0000
  FINS 0 0.0000 0.5000 0.5000
  APST 2 0 0 0 0
  LPRM Barge
END
F9_Fairing1:Falcon9R/f9_fair_1
  STATUS Landed Earth
  POS -74.6709908 31.0260834
  HEADING 252.48
  AFCMODE 7
END
F9_Fairing2:Falcon9R/f9_fair_2
  STATUS Landed Earth
  POS -74.6808710 31.0441824
  HEADING 284.31
  AFCMODE 7
END
END_SHIPS

BEGIN_ExtMFD
END

BEGIN_uap
END

 

[BrianJ]

Is this a good orbital injection towards L1? :shifty:

Hi,
without a dedicated navigation tool (e.g. an IMFD Map-In-Rotating-Frame), it's not easy to tell. You need to be able to interpret the IMFD Map display.
Here's what IMFD Map shows me for your current trajectory:

IMFD can't find an Apoapsis because the vessel is always moving away from Earth, so it's gone to "Using Ship" mode and only shows your Periapsis data.
Now, you do want an Apoapsis close to L1, so it seems logical to burn retrograde. I made a 1.5m/s dV retrograde(rel.Earth) burn, and brought the first Apoapsis down to ~1.51Gm, and it looks about right:

As a matter of interest, in between these two trajectories (if you make a ~0.8m/s dV burn retrograde) the trajectory starts to look more like the Genesis mission which had a much larger Lissajous orbit around L1. And you can get a stable 1/2 orbit around Earth, which makes me think that the dV for Lissajous-orbit-insertion will be lower (but you will need to add more orbit-normal dV because DSCOVR is at a low inclination ref.ecliptic).
Hope this helps.
Brian

 

[romanasul]

BrianJ I'm curious what your settings are for IMFD map? I mean the configuration acccuracy settings.

 

[BrianJ]

BrianJ I'm curious what your settings are for IMFD map? I mean the configuration acccuracy settings.

Hi,
well, usually I have the accuracy at maximum, but that restricts the length of projected trajectory IMFD Map will show, so for longer trajectories (e.g. Earth to Mars) I may lower the accuracy to get a longer plot on IMFD Map.
I usually have Hyperbolic Limit and Period Limit off.

Although, if you're planning a short trajectory and don't want the IMFD Map screen obscured by irrelevant post-intercept trajectory plots, turning on Period Limit or Hyperbolic Limit can be useful.

I turn off Tgt Weak Pe. if the intercept I want is not "weak" and IMFD Map is showing close-approaches that are not relevant (IMFD Map only shows max. 6 intercepts, the one you want maybe after that etc.) Similarly for One Pe./Ref setting.

Cheers,
Brian

 

[boogabooga]

Someone requested a playback of this mission from me, so here it is.

Be sure to choose the playback at recorded speed option. :tiphat: