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make -f Makefile.cvs
steffens
Code: Select all
make -f Makefile.cvs
produit wrote:Hi,
I am still interested in having INTEGRAL attitude right.
I have created a tentative file of (two year worth of) attitude
versus time in the format
suggested in documentation (jd quaternion)
it is in:
http://isdcul3.unige.ch/~produit/celestia/
But I need to test it now.
I did a checkout from sourceforge CVS. But there was no
configure script so I cannot compile.
I am using preferably mac but can use linux also if somebody can point
me to instructions how to build latest version.
If somebody can upload my file and try to use it.
If it is right the solar pannels should be turned towards the sun at all time
but should move a lot (every 20 minutes)
produit wrote:If somebody can upload my file and try to use it.
If it is right the solar pannels should be turned towards the sun at all time
but should move a lot (every 20 minutes)
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# Orbital elements obtained from JPL's Horizons ephemeris server
# Nov 22. 2002.
# by Selden Ball seb+cel@lns.cornell.edu
"INTEGRAL" "Sol/Earth"
{
Class "spacecraft"
Mesh "integral.3ds" # warning: 3MB
Radius 0.003 #4x4x6 meters w/o solar panels
EllipticalOrbit
{
Period 2.991956794955576E+00
SemiMajorAxis 8.770790078484899E+04
Eccentricity 8.234577927435308E-01
Inclination 5.305319831508738E+01
AscendingNode 1.014890638402147E+02
ArgOfPericenter 3.024416289547550E+02
MeanAnomaly 8.535622442451043E+01
Epoch 2452600.5
}
Albedo 0.7
SampledOrientation "integral.q"
BodyFrame { EquatorJ2000 { Center "Sol/Earth" } }
}
produit wrote:I have created a tentative file of (two year worth of) attitude
versus time in the format
suggested in documentation (jd quaternion)
it is in:
http://isdcul3.unige.ch/~produit/celestia/
selden wrote:...This could be shown in the current version of Celestia by having two models, one of the panels and one of the spacecraft, each with its own orientation and orbit files.
selden wrote:You don't need separate models for the two panels: both can be in the same model. Presumably both have the same orientation, unless (or until) a motor fails, of course.
If both panel and body models have the same size and orientation(*), you can either have them orbiting as separate bodies following the same orbit around the earth, or you can have the panels orbiting the spacecraft at a fixed relative position, specifying their rotations relative to the spacecraft.
----
* -- I've found this easiest to do by placing 6 invisible cubes (opacity = 0) at identical locations in the different models, placing them at positions on each axis outside the bounds of the largest body. That way the models all have the identical size and orientation. If the same radius and other parameters are specified for all of them in their SSC declarations, they'll follow one another as if they were one body.
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"Orion_to_Mars" "Sol" {
Mesh "orion_empty_noplatformfix.cmod"
Radius 0.02515 # 165 ft. tall
Class "spacecraft"
OrbitFrame {
EquatorJ2000 { Center "Sol" }
}
SampledOrbit "SB-jpl-11sep75.xyz"
RotationPeriod 1e32
RotationOffset 0
PrecessionPeriod 0.01
Obliquity -90.0
Albedo 0.2
}
# support structure
"Girders" "Sol" {
Mesh "girdersfix.cmod"
Radius 0.02515 # 165 ft. tall
Class "spacecraft"
OrbitBarycenter "Sol/Orion_to_Mars"
EllipticalOrbit
{
Period 1e32
SemiMajorAxis 0
}
RotationPeriod 1e32
RotationOffset 0
}
"Pulse_unit" "Sol" {
Mesh "pulse_unitfix.cmod"
Radius 0.02515 # 165 ft. tall
Class "spacecraft"
SampledOrbit "pls11sep75.xyz"
OrbitBarycenter "Sol/Orion_to_Mars"
RotationPeriod 1e32
RotationOffset 0
}
selden wrote:Chris,
Is there any way to specify an object's orientation relative to its .xyz trajectory without creating an accompanying orientation file?
In particular, can one specify how one of the object's axes should be oriented relative to the current xyz segment?
What I want to do is have the spacecraft's Y axis oriented tangent to the current trajectory segment while it's accelerating. Presumably this would be a fairly common situation.
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BodyFrame {
Center "Sol/Object"
TwoVector {
Primary {
Axis "y"
RelativeVelocity { Target "Sol" }
}
Secondary {
Axis "x"
RelativePosition { Target "Sol" }
}
}
}
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"vecalign00" "Sol" {
Class "spacecraft"
Mesh "vecalign00.cmod"
Radius 100
SampledOrbit "vecalign00.xyz"
}
"vecalignx" "Sol" {
Class "spacecraft"
Mesh "vecalignx.cmod"
Radius 100
SampledOrbit "vecalignx.xyz"
}
Modify "vecalignx" "Sol" {
BodyFrame {
Center "Sol/vecalignx"
TwoVector {
Primary {
Axis "x"
RelativeVelocity { Target "Sol" }
}
Secondary {
Axis "z"
RelativePosition { Target "Sol" }
}
}
}
}
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2000000 200 0 50000000
3000000 200 0 200000000
selden wrote:Previously in this thread Chris suggested a way that should align a model's axes relative to its trajectory vector.
Unfortunately, I've been unable to get it to work: my models refuse to change orientation. Specifying different axes to be aligned with an xyz trajectory's velocity vector does not cause the models to have different orientations.
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Modify "vecalignx" "Sol"
{
BodyFrame {
TwoVector {
Center "Sol/vecalignx"
Primary {
Axis "x"
RelativeVelocity { Target "Sol" }
}
Secondary {
Axis "z"
RelativePosition { Target "Sol" }
}
}
}
}
(Don't be distracted by the fact that the CMOD models' Y axes are aligned with the trajectories' Z direction. This is an issue for another discussion.)
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"vecalignz" "Sol" {
Class "spacecraft"
Mesh "vecalignz.cmod"
Radius 100
SampledOrbit "vecalignz.xyz"
}
Modify "vecalignz" "Sol" {
BodyFrame {
TwoVector {
Center "Sol/vecalignz"
Primary {
Axis "z"
RelativeVelocity { Target "Sol" }
}
Secondary {
Axis "y"
RelativePosition { Target "Sol" }
}
}
}
}
selden wrote:Chris,
There's still something strange about vecalignz
The vecalignz model flickers and when I select it and type a y (sync orbit) the distance to it intermittantly is MegaParsecs.