I have put a satellite into orbit during a previous mission a few weeks ago. This orbit is Tundra like : 78° Inc, 0.8 Ecc, and the orbital period is 1 day .
I need now to bring the satellite back to KSC, and I have a challenge to submit to the Orbiter experts in order to synchronise the DG orbit with the satellite CRG-00.
In the scenario below, you’ll find a DGIV in a circular orbit, aligned with CRG-00 orbiting plan, and about 80 sec before alignment with the satellite’s Pe.
The manoeuvre of DG would be as follows :
1-When aligned with target’s Pe, prograde burn to raise the ApA up to a certain value (let’s call it X).
2-When reaching Ap, 2nd prograde burn to reach a new ApA of 2.066M matching with target’s Pe.
3-When close to target’s Pe, prograde burn to match target’s ApA. The satellite distance and relative velocity should be close enough to perform an easy rendezvous manoeuvre.
My problem is that I don’t know how to accurately define X in order to synchronise DG at target’s Pe. I’ve found by guesswork and several attempts that approx. 1.580M is a good value, but I wonder if there is a tool to figure this out (I’m a beginner with Transx, and didn’t find a way to do it yet).
Any enlighted comments ?
For those who may be interested, this scenario is also a good training for aerobraking in order to decrease ApA and save fuel.
I need now to bring the satellite back to KSC, and I have a challenge to submit to the Orbiter experts in order to synchronise the DG orbit with the satellite CRG-00.
In the scenario below, you’ll find a DGIV in a circular orbit, aligned with CRG-00 orbiting plan, and about 80 sec before alignment with the satellite’s Pe.
Code:
BEGIN_DESC
80 sec before alignment with target Periapsis.
END_DESC
BEGIN_ENVIRONMENT
System Sol
Date MJD 55899.0795713693
END_ENVIRONMENT
BEGIN_FOCUS
Ship DG
END_FOCUS
BEGIN_CAMERA
TARGET DG
MODE Cockpit
FOV 40.21
END_CAMERA
BEGIN_HUD
TYPE Orbit
REF AUTO
END_HUD
BEGIN_MFD Left
TYPE Orbit
PROJ Ship
FRAME Equator
ALT
REF Earth
TARGET CRG-00
END_MFD
BEGIN_MFD Right
TYPE OSync
TARGET CRG-00
MODE Tg periapsis
LISTLEN 5
END_MFD
BEGIN_SHIPS
DG:DeltagliderIV
STATUS Orbiting Earth
RPOS -950361.74 -6349280.35 -1538354.55
RVEL -7244.104 1638.118 -2286.429
AROT 145.03 68.88 -112.24
VROT -0.00 0.07 0.21
PRPLEVEL 0:0.419015 1:0.985952 2:0.983333
IDS 0:45 100
NAVFREQ 525 94
XPDR 0
;-------------------------- Skin parameters must contain directory name of skin (without space)
MeshSkin Atv
;-------------------------- Cargo payload must contain name of config file or "none".(see doc)
CargoPayload none
NOSECONE 0 0.00
GEAR 0 0.00
AllDoorsState 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0.00 0 0 0.00
But1Cockpit 0 0 0 2 2 2 0 2 2 2 0 2 2 2 2 1 0 0 1 1 1 5
But2Cockpit 0 0 0 0 0 0 0 0 2 2 2 2 2 0 1 0 0 0 2 0 0 0
TransEffect -1
LifeBut1State 0 2 1 2 1 2 2 2 2 2 2 2 2 0 4
LevelBatt 100.0946
Emergency_power 10000.0000
VoltageStartBus 0.0000
VoltageGen1 96.2780
VoltageGen2 96.1134
VoltageGenBus 96.0000
O2tankALevel 99.7476
N2tankALevel 100.0000
O2tankBLevel 100.0000
N2tankBLevel 100.0000
CabinO2Level 21.3924
CabinCO2Level 600.0000
CabinTempLevel 23.9965
CabinPressure 14.7000
CabinMoistLevel 36.0000
CabinDustLevel 0.0001
CabinO2Setting 21.4000
CabinTempSetting 23.9965
CabinPressSetting 14.7000
AntennaTarget CRG-00
O2ConsumptionSetting 1
FuelConsumptionSetting 1
MainenginePower 1
;------------------Crew parameters UMMUCREW Function-Name-Age-CardiacPulse-WeightKg (fonction of Pilot must be: Capt)
NoOneOnBoard 0
NoPilotOnBoard 0
UMMUCREW Capt-Astronaut_1-42-58-90
UMMUCREW Spe-Astronaut_2-35-74-82
UMMUCREW Tech-Astronaut_3-26-79-71
FailGearFailure 0
FailGearCollapse 0
FailLeftMainEngine 0
FailRightMainEngine 0
FailHoverEngine 0
FailRcs 0
FailSurfaceControl 0
FailComputer 0
FailComputerBlueScreen 0
FailAutopilot 0
FailExtRadiator 0
FailAirbrake 0
FailNoseCone 0
FailCanopy 0
FailAntenna 0
FailLeftTurbo 0
FailRightTurbo 0
FailCargoDoor 0
SpacesuitTimer 0
UCGO @@0,1,0,0,@@1,1,0,0,@@2,1,0,0,@@3,1,0,0,
END
CRG-00:DGIVMTKSSAT
STATUS Orbiting Earth
RPOS 26903466.90 12252728.91 11949308.75
RVEL -1584.515 -3402.085 -1209.443
AROT 11.75 27.82 -107.36
AFCMODE 7
NAVFREQ 0 0
PowerUpStep 6
END
END_SHIPS
BEGIN_ExtMFD
END
BEGIN_uap
ENDThe manoeuvre of DG would be as follows :
1-When aligned with target’s Pe, prograde burn to raise the ApA up to a certain value (let’s call it X).
2-When reaching Ap, 2nd prograde burn to reach a new ApA of 2.066M matching with target’s Pe.
3-When close to target’s Pe, prograde burn to match target’s ApA. The satellite distance and relative velocity should be close enough to perform an easy rendezvous manoeuvre.
My problem is that I don’t know how to accurately define X in order to synchronise DG at target’s Pe. I’ve found by guesswork and several attempts that approx. 1.580M is a good value, but I wonder if there is a tool to figure this out (I’m a beginner with Transx, and didn’t find a way to do it yet).
Any enlighted comments ?
For those who may be interested, this scenario is also a good training for aerobraking in order to decrease ApA and save fuel.
