Take some signals and systems classes- Laplace and z transforms, Fourier analysis and such
Take some dynamics modeling classes. You can get a lot of that with a non linear controls class and prerequisite classes.
Stats, random variables, stochastic processes.
Kalman filter class for modeling and state estimation
System identification
Optimization
Nueral Networks, machine learning
Some programming classes so you can actually work on something (high level programs like matlab are good)