Hyperbolic eccentric anomaly error from KalmanEstimator

Hello,
I am trying to use KalmanEstimator for orbit determination with a NumericalPropagator and CartesianOrbit, but I’m receiving the following error:
“org.orekit.errors.OrekitException: unable to compute hyperbolic eccentric anomaly from the mean anomaly after 1,000,000 iterations”
Does KalmanEstimator represent trajectories as Keplerian at some point in the process, requiring the calculation of the eccentric anomaly? Why would the estimator need to calculate an eccentric anomaly if I am using CartesianOrbit and NumericalPropagator?
Thank you,
Erin

Hi @erinf

The Kalman can perform the estimation for any orbit type representation.
The default orbit type of the NumericalPropagator is equinoctial. Even if you are estimating cartesian parameters, the orbit type is equinoctial if you don’t update it. So, they are many orbit type transformations that are performed during an orbit determination (especially for the state transition matrix computation).

Usually, this error message highlights something not expected in the process.
Could you provide a code example in order to help you investigating your issue?

Regards,
Bryan

Hi Bryan,
Thank you for your reply - It turned out that my estimator was badly tuned, so I was able to solve the issue by tweaking the parameters.
Erin