I am a huge beginner in using Orekit and was looking for some help on understanding and getting orbit determination to work.
So far, I’ve used Orekit to simulate a satellite orbit and used an ElevationDetector to get azimuth and elevation (and range) of the satellite as it passes over a ground station. I am simulating FalconSAT3 using a TLE from N2YO.com. I plugged in the TLE into a “SGP4 Propagator” to generate the az/el points.
Now, I want to do a simple test to plug in those simulated azimuth and elevation points into an orbit determination estimator and see how close I can get to the simulated satellite parameters.
I’ve been following the very helpful guide of GorgiAstro on github(sorry I can’t link because I am new user)
and have made small modifications to make this work with AzEl instead of ranges, but when I run, I am getting an “unable to solve” run time error.
My “initial guess” is the same TLE that I used to simulate the orbit, so I expected the estimator to give me back the same/very close parameters.
I’ve attached a text file with the code snippet of my OD attempt. If it is easier, I can attach the beginning part with the code I used to get the simulated data too.
The variables: azArray, elArray, and timeStamps are arrays with the simulated data in
them that I used.
Some things I think might be wrong/I don’t understand
- To add the AngularAzEl measurement to the estimator, I needed to add a “ObservableSatellite” to the constructor. I gave this a propagator index of 0, but I don’t know what it is doing.
- Some objects needed a frame in the constructor. I have been using the variable “inertialFrame”, which is just FramesFactory.getEME2000(). Is it possible that I am using this improperly?
Let me know if you need more information!
odCodeSnippet.txt (3.7 KB)