Hi everyone,
i’m runing some Orekit code to deal with CR3BP. And it is really a good start point.
but there is a confusion for me about the normalized units used by orekit.bodies.CR3BPSystem. In its constructor, that is
public CR3BPSystem(final CelestialBody primaryBody, final CelestialBody secondaryBody, final double a, final double mu) {
...
this.mu = mu;
this.dDim = a;
this.vDim = FastMath.sqrt(mu1 / dDim);
this.tDim = 2 * FastMath.PI * dDim / vDim;
...
but the normalized units in the book “Dynamical systems, the three-body problem, and space mission design, Koon, Lo, Marsden, Ross”, which is referenced in Orekit, should be, in java,
this.mu = mu;
this.dDim = a;
this.tDim = FastMath.sqrt( FastMath.pow(a,3) / (primaryBody.getGM()+secondaryBody.getGM() );
this.vDim = a / this.tDim;
with the orignal literature is cited here, “L [the distance normalized units] is the distance between the centers of m1 and m2 , V = 2πL/T is the orbital velocity scale, T is the orbital period of m1 and m2”
the nondimensional CR3BP equations holds, requires the selected normalized units.
so, if the Orekit’s CR3BPSystem and CR3BPForceModel is consistent with the referened book, the normalized units will be the same.
or? is there any internal converstion and reasons to use the currernt units?
thanks